Patent Application
20240026379
The present invention belongs to the field of biotechnology and gene therapy. Specifically, the present invention relates to a method for transforming glial cell-derived cells into neurons, and a method for applying aforementioned method to repair nervous system damage or treat glial cell-derived tumors.
The main pathological changes caused by central nervous system injury and various neurodegenerative diseases in mammals are irreversible degeneration and necrosis of neurons and destruction of neural circuits. How to supplement and replace the dead and lost neurons in the injured and diseased brain or spinal cord, and reconstruct the neural circuit are the key steps of treatment. Because the self-repair ability of the central nervous system (brain and spinal cord) of adult mammals is very limited, it is difficult to make up for the loss of neurons by themselves.
Because the transplantation efficiency of exogenous neurons or neuro-derived cells is low, and there are potential risks of tumorigenicity and immunogenicity, in recent years, the emergence of cell reprogramming technology has brought revolutionary changes to regenerative medicine, and the induction of neurons by reprogramming astrocytes in vivo through the expression of single or combination of multiple transcription factors is expected to become an important new strategy of neuron replacement therapy.
Neuroglioma is referred to as glioma for short, also known as glioblastoma. It refers to all tumors of neuroepithelial origin in the broad sense, and tumors of various types of glial cells in the narrow sense. Glioma is one of the most lethal malignant tumors and the most common primary central nervous system tumor. It accounts for 30% of brain and central nervous system tumors and 80% of brain malignant brain tumors. It is a serious threat to human health. According to the classification scheme of the World Health Organization (WHO) in 1999, glioma is divided into astrocytoma, oligodendroglioma, ependymoma, mixed glioma, choroid plexus tumor, neuroepithelial histoma of uncertain origin, mixed neuroglial and neuroglial tumors, pineal parenchymal tumors, embryonal tumors, and neuroblastoma tumors. Glioma and normal nerve tissue grow in a crisscross manner, with unclear boundary. Tumor tissue is not easy to clean up and easy to relapse. At the same time, due to the existence of blood-brain barrier, common anti-tumor drugs have poor efficacy. At present, the treatment of glioma has not yet met the clinical needs of the medical community. In recent years, some studies have found that some neuro-derived transcription factors or combinations of transcription factors have been able to transform glioma cells into neuron-like cells in vitro or in vivo, and limit the proliferation of glioma cells. However, the existing transcription factors or combinations of transcription factors have only been proved to be used in vitro or in vivo with low conversion efficiency, which is difficult to achieve practical clinical application.
Therefore, finding suitable transcription factors or their combinations to induce glial cells to differentiate into active neurons in vivo is very important for the repair of brain and spinal cord nervous system. At the same time, using the reprogramming technology of transcription factors for reference to apply it to glial cell derived glioma is also a treatment plan that needs to be solved urgently at present.
The present invention provides a group of transcription factors and transcription factor combinations that synergistically promote the trans-differentiation of glial cells and reprogram them into functional neurons or neuron-like cells. The invention also provides a method for increasing the expression of this group of transcription factors in vivo or in vitro, and the application of this group of transcription factors in the preparation of drugs for nervous system diseases.
The first aspect of the invention provides a set of functional fragments that can synergistically promote the trans-differentiation of glial cells, wherein the functional fragments contain at least one functional fragment that promotes the expression of transcription factors, selected from those that promote the expression of transcription factors such as NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2.
In another preferred example, the trans-differentiation refers to the trans-differentiation or reprogramming of glial cells into functional neurons.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Asc11 transcription factor.
In another preferred example, the Asc11 is an enhanced Asc11, and its amino acid sequence is shown in SEQ ID No: 41.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of NeuroD1 transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Brn2 transcription factor.
In another preferred example, the functional fragments promoting the expression of the transcription factor at least include the functional fragment promoting the expression of the Ngn2 transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Gsx1 transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Tbr1 transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Dlx2 transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Ptf1a transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Pax6 transcription factor.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Otx2 transcription factor.
In another preferred example, the functional fragments combination contains at least two functional fragments that promote the expression of transcription factors, which are selected from the functional fragments that promote the expression of transcription factors such as NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2.
In another preferred example, the functional fragments promoting the expression of transcription factor at least include the functional fragment promoting the expression of Brn2 transcription factor and another functional fragment promoting the expression of transcription factor. The above another functional fragment promoting the expression of transcription factor is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as NeuroD1, Asc11 or Ngn2.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of NeuroD1 transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Brn2, Asc11 or Ngn2.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of Gsx1 transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Brn2, Tbr1, Dlx2, Ptf1a, Pax6 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Asc11, Ngn2 or Tbr1.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of Tbr1 transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Brn2, Gsx1, Dlx2, Ptf1a, Pax6 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Asc11, Ngn2 or Gsx1.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of Dlx2 transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Brn2, Tbr1, Gsx1, Ptf1a, Pax6 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Asc11, Ngn2 or Ptf1a.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of Ptf1a transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Brn2, Tbr1, Gsx1, Dlx2, Pax6 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Asc11, Ngn2 or Dlx2.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of Pax6 transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Brn2, Tbr1, Gsx1, Ptf1a, Dlx2 or Otx2 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Asc11, Ngn2 or Otx2.
In another preferred example, the functional fragments promoting the expression of transcription factors at least include the functional fragment promoting the expression of Otx2 transcription factor and another functional fragment promoting the expression of transcription factors. The above another functional fragment promoting the expression of transcription factors is selected from any functional fragment that promotes the expression of NeuroD1, Asc11, Ngn2, Brn2, Tbr1, Gsx1, Ptf1a, Dlx2 or Pax6 and other transcription factors; More preferably, the above another functional fragment that promotes the expression of transcription factors is selected from any functional fragment that promotes the expression of transcription factors such as Asc11, Ngn2 or Pax6.
In another preferred example, the functional fragments that promote the expression of transcription factors at least include the functional fragments that promote the expression of any transcription factor of Asc11 or Ngn2, and the other functional fragments that promote the expression of transcription factors, which are selected from any functional fragments that promote the expression of transcription factors such as NeuroD1, Brn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 or Otx2.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells at least include the functional fragments that promote the expression of the two transcription factors NeuroD1 and Brn2, or the functional fragments that promote the expression of the two transcription factors Gsx1 and Tbr1, or the functional fragments that promote the expression of the two transcription factors Dlx2 and Ptf1a, or the functional fragments that promote the expression of the two transcription factors Pax6 and Otx2.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells at least includes the combination of the functional fragments that can promote the expression of any transcription factor of Asc11 or Ngn2 and another functional fragments that can synergistically promote the trans-differentiation of glial cells. The above another functional fragments that can synergistically promote the trans-differentiation of glial cells are selected from the combination of functional fragments that promote the expression of NeuroD1 and Brn2 transcription factors, or the combination of functional fragments that promote the expression of Gsx1 and Tbr1 transcription factors, or the combination of functional fragments that promote the expression of Dlx2 and Ptf1a transcription factors, or the combination of functional fragments that promote the expression of Pax6 and Otx2 transcription factors.
The functional fragments that can synergistically promote the trans-differentiation of glial cells or the expression of transcription factors can be polynucleotides that encode the transcription factors, or functional proteins and peptides that are translated from polynucleotides, or small molecular drugs, macromolecular drugs, nucleic acid drugs that promote the expression of transcription factors, or polynucleotides or functional proteins that are located upstream of the transcription factors and can regulate the up-regulation of the expression of transcription factors, Peptides, small molecule drugs or macromolecular drugs, nucleic acid drugs, etc.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional segment that can promote the expression of transcription factors are the functional protein of NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2 or the nucleic acid sequence encoding the functional protein of transcription factors such as NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2; Preferably, the functional fragments that can synergistically promote the trans-differentiation of glial cells or promote the expression of transcription factors are derived from mammals; Further preferably, from human or non-human primate mammals.
In another preferred example, the combination of the functional fragments is selected from the following group:
In another preferred example, the combination of the functional fragments is selected from the following group: NeuroD1+Brn2; Gsx1+Tbr1; Dlx2+Ptf1a; Pax6+Otx2; Or a combination thereof.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional NeuroD1 protein, and the protein sequence is SEQ ID NO.: 1 or SEQ ID NO.: 2; The polynucleotide sequence encoding the NeuroD1 functional protein is shown in SEQ ID NO.: 3 or SEQ ID NO.: 4.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Brn2 protein, and the protein sequence is SEQ ID NO.: 5 or SEQ ID NO.: 6; The polynucleotide sequence encoding the Brn2 functional protein is shown in SEQ ID NO.: 7 or SEQ ID NO.: 8.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Asc11 protein, and the protein sequence is SEQ ID NO.: 9 or SEQ ID NO.: 10 or SEQ ID NO.: 41; The polynucleotide sequence encoding the Asc11 functional protein is shown in SEQ ID NO.: 11 or SEQ ID NO.: 12.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Ngn2 protein, and the protein sequence is SEQ ID NO.: 13 or SEQ ID NO.: 14; The polynucleotide sequence encoding the Ngn2 functional protein is shown in SEQ ID NO.: 15 or SEQ ID NO.: 16.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Gsx1 protein, and the protein sequence is SEQ ID NO.: 17 or SEQ ID NO.: 18; The polynucleotide sequence encoding the Gsx1 functional protein is shown in SEQ ID NO.: 19 or SEQ ID NO.: 20.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Tbr1 protein, and the protein sequence is SEQ ID NO.: 21 or SEQ ID NO.: 22; The polynucleotide sequence encoding the Tbr1 functional protein is shown in SEQ ID NO.: 23 or SEQ ID NO.: 24.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Dlx2 protein, and the protein sequence is SEQ ID NO.: 25 or SEQ ID NO.: 26; The polynucleotide sequence encoding the Dlx2 functional protein is shown in SEQ ID NO.: 27 or SEQ ID NO.: 28.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Ptf1a protein, and the protein sequence is SEQ ID NO.: 29 or SEQ ID NO.: 30; The polynucleotide sequence encoding the Ptf1a functional protein is shown in SEQ ID NO.: 31 or SEQ ID NO.: 32.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Pax6 protein, and the protein sequence is SEQ ID NO.: 33 or SEQ ID NO.: 34; The polynucleotide sequence encoding the Pax6 functional protein is shown in SEQ ID NO.: 35 or SEQ ID NO.: 36.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragment that can promote the expression of transcription factors are a functional Otx2 protein, and the protein sequence is SEQ ID NO.: 37 or SEQ ID NO.: 38; The polynucleotide sequence encoding the Otx2 functional protein is shown in SEQ ID NO.: 39 or SEQ ID NO.: 40.
In another preferred example, the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragments that can promote the expression of transcription factors are the modified Asc11 functional protein, and the protein sequence is shown in SEQ ID NO.: 41.
In another preferred example, when the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional segment that can promote the expression of transcription factors are functional protein, the sequence of the functional protein and SEQ ID NO.: 1, 2, 5, 6, 9, 10, 13, 14, 17, 18, 21, 22, 25, 26, 29, 30, 33, 34, 37, 38 and/or 41 have no less than 85% homology; More preferably, the sequence of the functional protein and SEQ ID NO.: 1, 2, 5, 6, 9, 10, 13, 14, 17, 18, 21, 22, 25, 26, 29, 30, 33, 34, 37, 38 and/or 41 sequence have no less than 95% homology; Preferably, the sequence homology of the functional protein with SEQ ID NO.: 1, 2, 5, 6, 9, 10, 13, 14, 17, 18, 21, 22, 25, 26, 29, 30, 33, 34, 37, 38 and/or 41 is not less than 99%.
In another preferred example, when the functional fragments that can synergistically promote the trans-differentiation of glial cells or the functional fragments that can promote the expression of transcription factors are the polynucleotide that encodes the functional protein, the sequence of the poly-nucleic acid that encodes the functional protein and SEQ ID NO.: 3, 4, 7, 8, 11, 12, 15, 16, 19, 20, 23, 24, 27, 28, 31, 32, 35, 36, 39 and/or 40 have a sequence homology of not less than 75%; More preferably, the sequence of the poly-nucleic acid encoding the functional protein and SEQ ID NO.: 3, 4, 7, 8, 11, 12, 15, 16, 19, 20, 23, 24, 27, 28, 31, 32, 35, 36, 39 and/or 40 have no less than 85% homology; Preferably, the sequence of the poly-nucleic acid encoding the functional protein and SEQ ID NO.: 3, 4, 7, 8, 11, 12, 15, 16, 19, 20, 23, 24, 27, 28, 31, 32, 35, 36, 39 and/or 40 have no less than 95% homology.
Preferably, the glial cells are any astrocytes, NG2 glial cells, oligodendrocytes, microglial cells, or glial cells in injured state, tumor cells derived from glial cells, etc. from human or non-human mammals; The glial cells in the injured state are glial cells in the state that the tissue or the surrounding environment of glial cells is in the state of mechanical trauma, stroke or neurodegenerative disease causing neuron death and apoptosis, which leads to the blockage or disorder of nerve signal transmission; The tumor cells derived from the glial cells are generally glioma cells, which are selected from astrocytoma, oligodendroglioma, ependymoma, mixed glioma, choroid plexus tumor, neuroepithelial histoma of uncertain origin, mixed tumor of neurons and neuroglia, pineal parenchyma tumor, embryonal tumor and neuroblastoma tumor derived from human or non-human mammals.
Preferably, the functional nerve cell or neuroid cell comprises at least one of the following features:
The second aspect of the invention provides a method for promoting the trans-differentiation and reprogramming of glial cells into functional neurons or neuron-like cells.
In another preferred example, the method is non-therapeutic and non-diagnostic.
In another preferred example, the method is in vitro.
In another preferred example, the method is therapeutic.
In another preferred example, the method includes the following steps: contact the functional fragments of the first aspect of the invention that can synergistically promote the gliocyte trans-differentiation with the gliocyte or rely on the delivery system to import, so as to make the gliocyte trans-differentiation and reprogramming into a functional neurons or neuron-like cells.
Preferably, the glial cells are any astrocytes, NG2 glia, oligodendrocytes, microglia, or glia in a damaged state, tumor cells derived from glia, etc. from human or non-human mammals; The glial cells in the injured state are glial cells in the state that the tissue or the surrounding environment of glial cells is in the state of mechanical trauma, stroke or neurodegenerative disease causing neuron death and apoptosis, which leads to the blockage or disorder of nerve signal transmission; The tumor cells derived from the glial cells are generally glioma cells, which are selected from astrocytoma, oligodendroglioma, ependymoma, mixed glioma, choroid plexus tumor, neuroepithelial histiocoma of uncertain origin, mixed tumor of neurons and neuroglia, pineal parenchyma tumor, embryonal tumor and neuroblastoma tumor derived from human or non-human mammals.
Any method of increasing the expression of transcription factors that can promote the trans-differentiation of glial cells, including but not limited to increasing the expression of any NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2 transcription factors in glial cells through direct contact or introduction with the glial cells, And promote the glial cells to display the characteristics of functional nerve cells or neuro-like cells.
The inducible factor or the functional fragment that promotes the expression of the transcription factor can be a polynucleotide encoding the transcription factor, or a functional protein or polypeptide after the translation of the polynucleotide, or a small molecule drug, a macromolecular drug, a nucleic acid drug that promotes the expression of any of the transcription factors NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2, or polynucleotides or functional proteins, peptides, small molecule drugs or macromolecular drugs, nucleic acid drugs located in the upstream of any transcription factor of NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2 and regulating the up-regulation of transcription factor expression. The inducible factor or the functional fragment that promotes the expression of the transcription factor is passively absorbed by the glia or reaches the glia through the delivery system to take effect.
The delivery system includes, but is not limited to an expression vector containing functional fragments that promote the expression of transcription factors, nanoparticles wrapped with functional fragments that promote the expression of transcription factors, exosomes wrapped with functional fragments that promote the expression of transcription factors, viral vectors or cell vectors (such as modified red blood cells or bacteria) wrapped with functional fragments that promote the expression of transcription factors, and targeted effectors (such as glial cell specific antibody, polypeptide or other targeted substances) that contain functional fragments that promote the expression of transcription factors.
In another preferred example, the functional fragment of the inducer or the promoter of the expression of the transcription factor is a polynucleotide encoding the transcription factor, and the polynucleotides are selected from the transcription factor functional polynucleotides of NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2; The polynucleotides need to be loaded in a viral or non-viral delivery system.
In another preferred example, the delivery system includes but is not limited to plasmids, viruses and cell vectors; It is preferably a viral vector, including but not limited to adenovirus vector, adeno-associated virus vector (AAV), retrovirus expression vector or lentivirus vector, etc.
In another preferred example, the expression vector containing transcription factor polynucleotides also contains glial cell-specific promoters. The promoters include, but are not limited to, GFAP promoter, NG2 promoter, Aldh1L1 promoter, IBA1 promoter, CNP promoter, LCN2 promoter or promoter variants after genetic engineering.
In another preferred example, the promoter is GFAP promoter, or GFAP promoter after genetic engineering. Preferably, the human hGFAP promoter (SEQ ID No: 42) can be transformed into a truncated version of 683 bp (SEQ ID No: 43).
In another preferred example, the expression vector containing transcription factor polynucleotides also contains one or more regulatory elements that regulate gene expression, which are used to enhance gene expression level. The regulatory elements include but are not limited to CMV enhancer, SV40 enhancer, EN1 enhancer, VP16 fusion protein or enhancer variants after genetic engineering, as well as SV40 poly A tailing signal, human insulin gene poly A tailing signal or WPRE (regulatory elements after the transcription of marmot hepatitis B virus), human MAR sequence or variants after genetic engineering.
In another preferred example, the regulatory element used to enhance expression is the active domain (SEQ ID NO: 44) of VP16 protein from Herpes simplex virus, wherein the coding sequence (SEQ ID NO: 45) of VP16 can be loaded individually or in a string, and the fusion protein of VP16-transcription factor DNA binding region can be expressed through glial cell-specific promoter.
In another preferred example, the regulatory element used to enhance expression comes from the enhancer of simian vacuolating virus 40 SV40 (SEQ ID NO: 46). Inserting it into the glial cell-specific promoter can enhance the activity of the promoter and improve the efficiency of neuron induction.
In another preferred example, the expression vector containing transcription factor polynucleotides can also contain other functional fragments at the same time. The other functional fragments can be reporter genes or other transcription factor functional fragments with reprogramming function, including but not limited to selected from NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2, etc; Preferably, the same vector can contain polynucleotide fragments of at least two transcription factors, which can be expressed under one glial-specific promoter or under two glial-specific promoters respectively. When two or more transcription factors are in the transcript of a single promoter, the promoter is connected with the open reading frame of multiple transcription factors through multiple cis-transon elements. Among them, the transcription factors are separated by IRES or 2A polypeptide (P2A) elements to achieve the expression of multiple transcription factors (Pharmaceutics 2019, 11 (11), 580; The IRES sequence used in the invention is copied from Addgene #69550; P2A sequence is copied from Addgene #130692). The combination of the two transcription factors is selected from the combination of NeuroD1 and Brn2 transcription factors, the combination of Gsx1 and Tbr1 transcription factors, the combination of Dlx2 and Ptf1a transcription factors, the combination of Pax6 and Otx2 transcription factors, and the combination of Asc11 and Ngn2 transcription factors. The molar concentration ratio of the expression of the two transcription factors is 4:1-1:4; Preferably, the molar concentration ratio of the expression amount of the two transcription factors is 2:1 to 1:2; Further preferably, the optimal molar concentration ratio of the expression of the two transcription factors is 1:1.
In another preferred example, the same vector contains at least two transcription factors, and one of them is Asc11 or Ngn2. At this point, the molar concentration ratio of the expression amount of Asc11 or Ngn2 is not less than 20%; Preferably, the molar concentration ratio of the expression amount of Asc11 or Ngn2 is not less than 33%; Further preferably, the molar concentration ratio of the expression amount of Asc11 or Ngn2 is not less than 50%; The vector includes any combination of the following transcription factors:
In another preferred example, one or more expression vectors containing different transcription factor polynucleotides can also be used at the same time. The transcription factors are selected from the functional polynucleotides of the transcription factors of NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2; Preferably, the vector combination is selected from the vector combination containing the transcription factor NeuroD1 and the transcription factor Brn2, the vector combination containing the transcription factor Gsx1 and the transcription factor Tbr1, the vector combination containing the transcription factor Dlx2 and the transcription factor Ptf1a, and the vector combination containing the transcription factor Pax6 and the transcription factor Otx2. The molar concentration ratio of the expression of the two transcription factors is 4:1-1:4; Preferably, the molar concentration ratio of the expression amount of the two transcription factors is 2:1 to 1:2; Further preferably, the molar concentration ratio of the expression amount of the two transcription factors is 1:1.
In another preferred example, one or more expression vectors containing different transcription factor polynucleotides can also be used at the same time, including at least the combination of expression vectors containing Asc11 or Ngn2 polynucleotides and other transcription factor vectors, wherein the molar concentration ratio of the expression amount of Asc11 or Ngn2 should not be less than 20%, and preferably, the molar concentration ratio of the expression amount of Asc11 or Ngn2 should not be less than 33%; Further preferably, the molar concentration ratio of the expression amount of Asc11 or Ngn2 should not be less than 50%; The expression vector is selected from any combination of the following vectors:
In another preferred example, the expression vector of the functional fragment containing the transcription factor polynucleotide is a lentivirus vector; Lentiviral vector contains viral ITR sequence, CAG promoter, coding frame of functional fragment of transcription factor polynucleotide, post transcriptional regulatory element WPRE, etc; The expression vector can also contain a reporter gene, but the reporter gene is not necessary in practical application. The lentiviral vector from 5′ to 3′ ends can successively include the following elements: viral ITR sequence+CAG promoter+coding frame of transcription factor polynucleotide and green fluorescent protein GFP+post transcriptional regulatory element WPRE+viral ITR sequence+promoter and coding frame of ampicillin resistance gene. Among them, the coding frame of GFP and the promoter and coding frame of ampicillin resistance gene are not necessary. Preferably, the polynucleotides of the transcription factors are selected from the functional polynucleotides encoding NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2; Specifically, from the sequence of SEQ ID NO.: 3, 4, 7, 8, 11, 12, 15, 16, 19, 20, 23, 24, 27, 28, 31, 32, 35, 36, 39 and/or 40.
In another preferred example, the expression vector of the functional fragment containing the transcription factor polynucleotide is GFAP-AAV vector; GFAP-AAV vector contains viral ITR sequence, CMV enhancer, human GFAP promoter, coding frame of functional fragment of transcription factor polynucleotide, post transcriptional regulatory element WPRE, etc; The expression vector can also contain a reporter gene, but the reporter gene is not necessary in practical application. The GFAP-AAV expression vector can successively include the following elements from the 5′ to 3′ end: viral ITR sequence+CMV enhancer+human GFAP promoter+transcription factor polynucleotide and coding frame of red fluorescent protein mCherry+post transcriptional regulatory element WPRE+viral ITR sequence+promoter and coding frame of ampicillin resistance gene, wherein the coding frame of red fluorescent protein mCherry and the promoter and coding frame of ampicillin resistance gene are not necessary. Preferably, the polynucleotides of the transcription factors are selected from the functional polynucleotides encoding NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and/or Otx2, specifically, from the sequence of SEQ lD NO.: 3, 4, 7, 8, 11, 12, 15, 16, 19, 20, 23, 24, 27, 28, 31, 32, 35, 36, 39 and/or 40.
In another preferred example, the GFAP-AAV expression vector can include the following elements from the 5′ to 3′ ends: viral ITR sequence+SV40 enhancer+human GFAP promoter+transcription factor polynucleotide+post transcriptional regulatory element WPRE+viral ITR sequence.
In another preferred example, the GFAP-AAV expression vector can include the following elements from the 5′ to 3′ end in turn: viral ITR sequence+CMV enhancer+human GFAP promoter+VP16 fusion protein+DNA binding region of transcription factor+post transcriptional regulatory element WPRE+viral ITR sequence.
In another preferred example, the GFAP-AAV expression vector can include the following elements from the 5′ to 3′ ends: viral ITR sequence+CMV enhancer+human truncated GFAP promoter+transcription factor polynucleotide+post transcriptional regulatory element WPRE+viral ITR sequence.
In another preferred example, the GFAP-AAV expression vector from the 5′ to the 3′ end can successively include the following elements: viral ITR sequence+enhancer of SV40+promoter of human truncated GFAP+VP16 fusion protein+DNA binding region of transcription factor+post transcriptional regulatory element WPRE+viral ITR sequence.
In another preferred example, the GFAP-AAV expression vector can include the following elements from the 5′ to 3′ ends: viral ITR sequence+SV40 enhancer+human truncated GFAP promoter+transcription factor polynucleotide+post transcriptional regulatory element WPRE+viral ITR sequence.
In another preferred example, the GFAP-AAV expression vector can include the following elements from the 5′ to 3′ end in turn: viral ITR sequence+enhancer of SV40+promoter of human GFAP+VP16 fusion protein+DNA binding region of transcription factor+post transcriptional regulatory element WPRE+viral ITR sequence.
In another preferred example, the GFAP-AAV expression vector can include the following elements from the 5′ to 3′ ends in turn: viral ITR sequence+CMV enhancer+human truncated GFAP promoter+VP16 fusion protein+DNA binding region of transcription factors+post transcriptional regulatory element WPRE+viral ITR sequence.
The third aspect of the invention provides a pharmaceutical composition, which comprises:
In another preferred example, the pharmaceutical composition is a liquid preparation and a lyophilized preparation.
In another preferred example, the pharmaceutical composition is an injection.
In another preferred example, the pharmaceutical composition comprises:
In another preferred example, the above combination is the combination of enhanced Asc11 and at least one selected from the following group: NeuroD1, Brn2, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2.
In another preferred example, the above combination is a combination of Asc11 and at least one selected from the following group: NeuroD1, Brn2, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2.
In another preferred example, the above combination is a combination of Ngn2 and at least one selected from the following group: NeuroD1, Brn2, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2.
The fourth aspect of the invention provides an artificial reprogrammed neuron or neuron-like cell, which is obtained from glial cells through trans-differentiation and reprogramming.
In another preferred example, the artificial reprogrammed neuron or neuron-like is prepared by the method described in the second aspect of the invention.
The fifth aspect of the present invention provides the use of the pharmaceutical composition described in the third aspect of the present invention or the artificial reprogrammed neurons or neuron-like cells in the fourth aspect, that is, they are used to prepare drugs for gene therapy of nervous system diseases. Preferably, the nervous system disease is a nervous system injury or a glioma derived from glial cells.
It should be understood that within the scope of the invention, the above technical features of the invention and the technical features specifically described in the following (according to the embodiment) can be combined with each other to form a new or preferred technical solution. Limited by space, I will not repeat it here.
After extensive and in-depth research, the inventor unexpectedly discovered a number of transcription factors or combinations of transcription factors with the function of trans-differentiation and reprogramming, the method of transforming glial cells into neurons, and the neurons which are able to efficiently convert glial cells into neuron cells with electrophysiological functions in vitro or in vivo. Based on such findings, the inventor further explored the application scenarios of transcription factors and their combinations. The combination of some specific transcription factors can synergistically significantly promote glial cells to differentiate into neurons. The method of the invention is applied to explore the application of nerve injury repair or brain glioma drug development, especially in the animal model of glioma, and it is observed that the reprogramming results in the withdrawal of glioma cells from the cell cycle, the tumor size of the animal is significantly reduced, and the survival time is significantly prolonged. Therefore, this batch of transcription factors or combinations of transcription factors with the function of trans-differentiation and reprogramming are expected to be used in the development of nerve injury repair drugs or glioma drugs.
The term “administration” refers to the physical introduction of the product of the invention into the subject using any of the various methods and delivery systems known to those skilled in the art, including intravenous, intracerebral, intratumoral, intramuscular, subcutaneous, intraperitoneal, spinal cord or other parenteral administration routes, such as injection or infusion.
The term “about” may refer to a value or composition within the acceptable error range of a specific value or composition determined by a person skilled in the art, which will depend in part on how to measure or measure the value or composition. Generally, “about” means±10% or ±20%. For example, about 1:1 means (1±0.2):(1±0.2); Or (1±0.1):(1±0.1).
As used in this article, the term “reprogramming” generally refers to the process of regulating or changing the biological activity of a cell and transforming it from one biological state to another, usually including differentiation (from progenitor cell to terminal cell), dedifferentiation (from terminal cell to pluripotent stem cell), trans-differentiation (from one terminal cell to another terminal cell), dedifferentiation (from terminal cell to progenitor cell) The process of changing the fate of cells, such as trans-differentiation (from one kind of progenitor cell to the terminal cell naturally differentiated from another kind of progenitor cell).
In the present invention, the “trans-differentiation” or “reprogramming” or “trans-differentiation reprogramming” specifically refers to the process from one terminal cell to another, specifically, to the process of transforming glial cells into functional nerve cells or neuro-like cells.
Transcription Factor
The present invention provides a group of transcription factors with reprogramming function. These transcription factors and their combinations have excellent trans-differentiation ability and can be used to promote the efficiency of glial cell trans-differentiation into neurons.
As used herein, the term “transcription factor of the present invention” refers to one or a group of transcription factors necessary for the differentiation of nerve cells selected from the following groups: NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6 and Otx2. Preferably, the transcription factor of the present invention comprises at least two of the said transcription factors.
NeuroD1 functional fragment is a polynucleotide or its expressed protein fragment that is derived from mammals and encodes the transcription factor of Neurological differentiation 1. NeuroD1 is a bHLH (basic helix-loop-helix) transcription factor. For example, the ID # of NeuroD1 molecule from human is 4760 in GenBank, and its protein sequence is shown in SEQ ID NO.: 1; NCBI Reference Sequence: NM_002500.5, CDS sequence is shown in SEQ ID NO.: 3.
Brn2 functional fragment, also known as POU3F2, Oct7 or N-Oct3, is a polynucleotide or its expressed protein fragment encoding Pou class 3 homeobox 2 transcription factor derived from mammals. Brn2 is a family of neurocell-specific POU-III transcription factors. For example, Brn2 molecule from humans has ID #5454 in GenBank, and its protein sequence is shown in SEQ ID NO.: 5; NCBI Reference Sequence: NM_005604.4, CDS sequence is shown in SEQ ID NO.: 7.
The functional fragment of Asc11 is a polynucleotide or its expressed protein fragment encoding the transcription factor of Achaete-scute homolog 1 derived from mammals. Asc11 is a bHLH (basic helix-loop-helix) transcription factor. For example, the ID # of Asc11 molecule from human is 429 in GenBank, and its protein sequence is shown in SEQ ID NO.: 9; NCBI Reference Sequence: NM_004316.4, CDS sequence is shown in SEQ ID NO.: 11.
The functional fragment of Ngn2, also known as Neurog2, is a polynucleotide or its expressed protein fragment encoding Neurogenin-2 transcription factor derived from mammals. Ngn2 is a bHLH (basic helix-loop-helix) transcription factor. For example, the ID # of Ngn2 molecule from human is 63973 in GenBank, and its protein sequence is shown in SEQ ID NO.: 13; NCBI Reference Sequence: NM_024019.4, CDS sequence is shown in SEQ ID NO.: 15.
The functional fragment of Gsx1, also known as Gshl, is a polynucleotide or its expressed protein fragment that is derived from mammals and encodes GS homeobox 1 transcription factor. The binding site of Gsx1 in DNA sequence is 5 ‘-GC [TA] [AC] ATTA [GA]-3’. For example, the ID # of Gsx1 molecule from human is 219409 in GenBank, and its egg white sequence is shown in SEQ ID NO.: 17; NCBI Reference Sequence: NM_145657.3, CDS sequence is shown in SEQ ID NO.: 19.
Tbr1 functional fragment is a polynucleotide or its expressed protein fragment that is derived from mammals and encodes T-box brain transcription factor 1 transcription factor. Tbr1 is a T-box transcription factor. For example, the ID # of Tbr1 molecule from human is 10716 in GenBank, and its protein sequence is shown in SEQ ID NO.: 21; NCBI Reference Sequence: NM_006593.4, CDS sequence is shown in SEQ ID NO.: 23.
Dlx2 functional fragment is a polynucleotide or its expressed protein fragment that is derived from mammalian and encodes the transcription factor of distal-less homeobox 2. Dlx2 is a transcription factor that participates in the terminal differentiation of intermediate neurons. For example, the ID # of Dlx2 molecule from human is 1746 in GenBank, and its protein sequence is shown in SEQ ID NO.: 25; NCBI Reference Sequence: NM_004405.4, CDS sequence is shown in SEQ ID NO.: 27.
Ptf1a functional fragment is a polynucleotide or its expressed protein fragment that is derived from mammals and encodes the transcription factor of pancreas-associated transcription factor 1a. Ptf1a is a transcription factor involved in pancreatic development. For example, the ID # of Ptf1a molecule from human is 256297 in GenBank, and its protein sequence is shown in SEQ ID NO.: 29; NCBI Reference Sequence: NM_178161.3, CDS sequence is shown in SEQ ID NO.: 31.
Pax6 functional fragment is a polynucleotide or its expressed protein fragment that is derived from mammalian and encodes the paired box 6 transcription factor. Pax6 is a key transcription factor involved in the development of neural tissue. For example, the ID # of Pax6 molecule from human is 5080 in GenBank, and its protein sequence is shown in SEQ ID NO.: 33; NCBI Reference Sequence: NM_000280.5, CDS sequence is shown in SEQ ID NO.: 35.
Otx2 functional fragment is a polynucleotide or its expressed protein fragment that is derived from mammalian and encodes the transcription factor of orthodentile homeobox 2. Otx2 belongs to the transcription factor of the subfamily of bicoid homologous domain. For example, the ID # of Otx2 molecule from human is 5015 in GenBank, and its protein sequence is shown in SEQ ID NO.: 37; NCBI Reference Sequence: NM_001270523.2, CDS sequence is shown in SEQ ID NO.: 39.
The present invention has no special restrictions on any method that can promote the expression of the functional fragments of the above transcription factors, including but not limited to promoting the expression or activity of any NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2 transcription factors in the glial cells by direct contact or introduction of the inducible factor or the functional fragments that can promote the expression of the transcription factors, and promote the glial cells to display the characteristics of functional nerve cells or neuro-like cells; The inducible factor or the functional fragment that promotes the expression of the transcription factor can be a polynucleotide encoding the transcription factor, or a functional protein or polypeptide after the translation of the polynucleotide, or a small molecule drug, a macromolecular drug, a nucleic acid drug that promotes the expression of any of the transcription factors NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2, or polynucleotide or functional protein, polypeptide, small molecule drug or macromolecule drug located upstream of any transcription factor of NeuroD1, Brn2, Asc11, Ngn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2. It is absorbed passively by glial cells or delivered to glial cells to take effect.
The method of promoting the expression of the functional fragments of the above transcription factors can also be obtained by CRISPR/dCas9 targeting the expression of the DNA-activated genes of the relevant transcription factors, or by CRISPR/Cas13 targeting the relevant transcription factor RNA to improve the expression of the functional proteins of the transcription factors.
Those skilled in the art can screen the promotion methods of the above transcription factors according to the existing database. It should be understood that, based on the function of the transcription factors disclosed in the present invention on the trans-differentiation of glial cells and the inhibition of neural injury repair and glioma cells, those skilled in the art can reasonably foresee that any substance that can promote the above transcription factors will have the function on the trans-differentiation of glial cells and the inhibition of neural injury repair and glioma cells.
Preferably, the reprogrammed transcription factor of the invention can be used in combination with the modified expression element to further improve the expression of the transcription factor of the invention.
Glial Cell
As used herein, the term “Neuroglia cell” or “glial cell” can be used interchangeably, referring to another large group of cells in the nerve tissue except for neurons, which are widely distributed in the central and peripheral nervous system. In mammals, the proportion of glial cells to neurons is about 10:1. The glial cells in the central nervous system mainly include astrocytes, NG2 glia, oligodendrocytes and microglia. Glial cells perform many physiological functions, including biochemical support (such as forming blood-brain barrier), provide nutrition for neurons, and maintain extracellular ion balance. In the state of injury or disease, glial cells will be activated and proliferated, and participate in the repair and scar formation after brain and spinal cord injury, but cannot differentiate into neurons. The key feature different from neural stem cells is that neural stem cells are self-replicating cells that have not fully differentiated, and have the potential to differentiate into neurons and various glial cells, while glial cells are end-differentiated cells.
The glial cells described in the invention are any astrocytes, NG2 glia, oligodendrocytes, microglia, or glial cells in the injured state, tumor cells derived from glial cells, etc. from human or non-human mammals; The glial cells in the injured state are glial cells in the state that the tissue or the surrounding environment of glial cells is in the state of mechanical trauma, stroke or neurodegenerative disease causing neuron death and apoptosis, which leads to the blockage or disorder of nerve signal transmission; The tumor cells derived from the glial cells are generally glioma cells, which are selected from astrocytoma, oligodendroglioma, ependymoma, mixed glioma, choroid plexus tumor, neuroepithelial histiocoma of uncertain origin, mixed tumor of neurons and neuroglia, pineal parenchyma tumor, embryonal tumor and neuroblastoma tumor derived from human or non-human mammals.
Glioma Cells
As used in this article, the term “neuroglioma” is referred to as “glioma” for short, also known as “oligodendroglioma”. It refers to all tumors of neuroepithelial origin in the broad sense, and tumors of various types of glial cells in the narrow sense. Glioma is one of the most lethal malignant tumors and the most common primary central nervous system tumor, accounting for 30% of brain and central nervous system tumors and 80% of brain malignant brain tumors. It is a serious threat to human health. According to the classification scheme of the World Health Organization (WHO) in 1999, it can be divided into astrocytoma, oligodendroglioma, ependymoma, mixed glioma, choroid plexus tumor, neuroepithelioma of uncertain origin, mixed neuroglioma and neuroglia, pineal parenchyma tumor, embryonal tumor and neuroblastoma tumor.
The glioma cells that can be used in the present invention are not particularly limited, including various gliomas from the mammalian central nervous system, such as astrocytoma, oligodendroglioma, ependymoma or neuroblastoma, preferably astrocytoma or neuroblastoma.
In the present invention, the transcription factor with trans-differentiation function and the combination of transcription factors have the ability to induce glioma cells to transform into neurons/neuron-like cells, and display the unique markers of neurons: DCX, Tuj1, Map2, NeuN, Synapsin I. At the same time, the proliferation of glioma was significantly reduced, the tumor growth was slowed down, and the degree of malignancy was decreased.
Delivery System
As used herein, the term “delivery system” has no special restriction. It can be an expression vector containing polynucleotide sequences encoding the transcription factors into glial cells or glioma cells. For example, virus vector can be any virus that can be used, and has the characteristics of transmitting its genome, bringing genetic material into other cells for infection. It can occur in intact living body or cell culture. Including lentivirus vector, adenovirus vector, adeno-associated virus vector, herpes virus vector, pox virus vector, etc.
The delivery system can also be a new type of nanoparticles, such as liposome nanoparticles, metal nanoparticles, polymer nanoparticles, etc., which are used to load the functional fragments of the transcription factor or the molecular entities that promote the expression or activity of the transcription factor, and deliver to the periphery of the target cell or enter the target cell.
The delivery system can also be an exocrine body that contains a functional segment of the transcription factor or a molecular entity that promotes the expression or activity of the transcription factor, or a modified red blood cell or bacteria that contains a functional segment of the transcription factor or a molecular entity that promotes the expression or activity of the transcription factor.
In addition, the delivery system can also combine molecules with targeted functions, such as specific monoclonal antibodies and polypeptides targeting glial cells or glioma cells, which can better promote the functional fragments of the transcription factor or promote the targeting of the functional fragments of the molecular entities with increased expression or activity of the transcription factor on glial cells or glioma cells, and increase the efficiency of inducing glial cell trans-differentiation and anti-tumor.
Inducing Method
The invention also provides a method for inducing glial cells or glioma cells to differentiate into neuron cells or neuron-like cells in vitro and in vivo, so as to achieve the purpose of nerve repair or anti-tumor. The term “inducer” refers to any molecular entity that promotes the expression or activity enhancement of the transcription factor functional fragment of the present invention.
In vitro, the functional fragments containing the transcription factor or the molecular entity promoting the expression or activity enhancement of the functional fragments of the transcription factor and its delivery system can be contacted or applied (for example, injected) to the target cells cultured in vitro, so that the glial cells can be passively absorbed or reach the glial cells through the delivery system for effect, so as to achieve the differentiation of neurons in vitro and inhibit the proliferation of tumor cells. The cells successfully transdifferentiated in vitro can also be transplanted to achieve nerve repair at the nerve injury site.
In vivo, the functional fragments containing the transcription factor or the molecular entity promoting the expression or activity enhancement of the functional fragments of the transcription factor and its delivery system can be contacted or applied (for example, injected) to the nerve injury site or tumor focus, so that the glial cells can be passively absorbed or reach the glial cells through the delivery system for effect, so as to achieve the differentiation of neurons in vitro and inhibit the proliferation of tumor cells. The method of direct induction in vivo will help to repair nerve injury in situ and inhibit tumor in situ.
At the same time, in combination with molecular targeting technology, the delivery system containing the functional fragment of the transcription factor or the molecular entity that promotes the expression and activity of the functional fragment of the transcription factor is installed with a specific molecular target of glioma or glioma, which can achieve the induction of neuronal trans-differentiation through ectopic injection.
Pharmaceutical Composition and Mode of Administration
The invention also provides a drug composition, which contains any molecular entity or its delivery system that promotes the expression or activity enhancement of the transcription factor functional fragments, or the functional neuron group after the trans-differentiation of the transcription factor functional fragments or the molecular entity that promotes the expression and activity enhancement of the transcription factor functional fragments in vitro, as well as other pharmaceutically acceptable vectors.
The pharmaceutical composition of the invention usually contains AAV virus particles of 1010-1013 PFU, preferably, AAV virus particles of 1011-1013 PFU, and more preferably, AAV virus particles of 1010-1012 PFU.
The pharmaceutical composition of the invention usually contains lentivirus particles of 107-1010 PFU, preferably, lentivirus particles of 107-109 PFU, and more preferably, lentivirus particles of 108-109 PFU.
The pharmaceutical composition of the invention usually contains adenovirus particles of 108-1011 PFU, preferably, adenovirus particles of 108-1010 PFU, and more preferably, adenovirus particles of 109-1010 PFU.
As used herein, the term “pharmaceutically acceptable carrier” refers to the carrier used for the administration of therapeutic agents, including various excipients and diluents. They are not necessary active ingredients themselves, and there is no excessive toxicity after application. A suitable carrier is well known to those skilled in the art. In the composition, the pharmaceutically acceptable carrier may contain liquid, such as water, saline and buffer. In addition, there may also be auxiliary substances in these carriers, such as fillers, lubricants, flow aids, wetting agents or emulsifiers, pH buffer substances, etc. The carrier can also contain cell transfection reagents.
Generally, the drug composition of the present invention can be obtained by mixing the expression vector with a pharmaceutically acceptable vector.
The method of administration of the composition described in the present invention is not particularly limited. Representative examples include but are not limited to: intravenous injection, subcutaneous injection, brain injection, intrathecal injection, spinal injection, etc.
Therapeutic Application
The molecular entity or its delivery system containing any functional fragment of the transcription factor that promotes the expression or activity enhancement, or the functional nerve group described in the present invention can be used to prepare drugs for repairing nerve injury or inhibiting the proliferation and deterioration of glioma.
The invention innovatively obtains a batch of transcription factors with reprogramming function, and explores the ability of transcription factors and their combinations to transdifferentiate, which can be potentially applied in different scenarios: for example, for the repair of nerve injury, the medium and high efficiency transcription factors and combinations of transcription factors can be selectively used according to the injury situation; For gliomas, a combination of transcription factors and transcription factors with higher transformation efficiency is needed to quickly regulate the malignant degree of gliomas.
The invention also further modifies the expression element of the transcription factor used for gene therapy, and significantly improves the efficiency of the transcription factor to promote glial cells to differentiate into neurons. In particular, the combination of transcription factors used in the present invention can transform human glioma cells into neurons, and cause glioma cells to withdraw from the cell cycle, thus no longer proliferate and grow. In the glioma model, the injection of adeno-associated virus containing the transcription factor combination can significantly reduce the tumor size and prolong the survival time of the animal.
Compared with the prior art, the main advantages of the invention include:
The present invention will be further described in combination with specific embodiments. It should be understood that these embodiments are only used to illustrate the invention and not to limit the scope of the invention. The following experimental methods without specific conditions are usually in accordance with conventional conditions, such as those described in the Molecular Cloning: Laboratory Manual (Sambrook et al., New York: Cold Spring Harbor Laboratory Press, 1989), or the conditions recommended by the manufacturer. Unless otherwise stated, percentages and portions are percentages and portions by weight.
Materials and Methods
General Method
Human Glioma Cell Culture
Human glioma cell lines U251 and U87 (purchased from the cell bank of Shanghai Institute of Life Sciences, Chinese Academy of Sciences) were cultured in a 37° C. incubator containing 5% CO 2. The culture medium was DMEM medium containing 10% fetal bovine serum and 1% penicillin/streptomycin. Add lentivirus, change the solution into inducing medium (DMEM, 2% B-27, 1% PS) 12 hours after infection, and then change the solution into nerve medium DMEM/F-12, 2% B-27, 1% PS, 20 ng/ml BDNF, 20 ng/ml GDNF after 48 hours. Change half of the culture medium every three days.
Immunostaining
The immunostaining of cultured cells was carried out according to “Direct conversion of fibroblasts to functional neurons by defined factors” (Vierbuchen, T. et al. Nature 463, 1035-1041 (2010)). The immunostaining test of tissue sections was carried out according to the published methods. The first antibody used in immune coloration includes: mouse anti-NeuN (Millipore, 1:100), rabbit anti-Dsred (Clontech, 1:500), mouse anti-Tuj1 (Covance, 1:500), mouse anti-Map2 (Sigma, 1:500), rabbit anti-GFP (Invitrogen, 1:1000), chip anti-GFP (Invitrogen, 1:1000), rabbit anti-Synapsin I (Millipore, 1:1000), rabbit anti-VGLUT1 (Synaptic Systems, 1:500), rabbit anti-Ki67 (1:200; RM-9106; Thermo Fisher Scientific), mouse anti-BrdU(1:200; B2531; Sigma). FITC-, Cy3- and Cy5-coupled secondary antibodies were purchased from Jackson Immunoresearch.
BrdU(5-bromodeoxyuracil nucleoside) Labeling and Cell Proliferation Experiment
The cultured human glioma cells were added with 10 mM BrdU (Sigma) and incubated for 2 hours or continuously according to the experimental requirements. The color of BrdU was detected by anti-BrdU antibody. The proliferating cells were also tested with Ki67 antibody. In addition, when evaluating the growth of glioma in 24 orifice plate (5×10 4 cells/well), count the number of cells at different time points (days 0, 3, 7, 14 and 21).
Glial Cell Trans-Differentiation Model In Vitro
(1) Plasmid Construction and Virus Infection
On the vector template of FUGW-IRES-EGFP (refer to the document Efficient transfer, integration, and sustained long term expression of the transgene in adult rat brain injected with a lentiviral vector. Proc Natl Acad Sci USA 93:11382-11388 for vector information), replace the CAG promoter with the cloned human NG2 promoter, and then construct the polynucleotide fragment of the transcription factor onto the lentivirus vector to generate hNG2-transcription factor-IRES-EGFP lentivirus plasmid. The packaging of lentivirus refers to the literature “Production and purification of lentivirus vectors” (Tiscornia, G., Singer, O. & Verma, I. M. Nat. Protocol. 1, 241-245 (2006)). The lentivirus was added to NG2 cells after 24 hours of plate culture, and the culture medium was changed after 24 hours of infection: DMEM/F12, B27, Glutamax and penicillin/streptomycin. After 6-7 days of infection, brain-derived neurotrophic factor (BDNF; PeproTech, 20 ng/ml) was added to the culture medium every three days.
(2) NG2 Cells Differentiate into Neurons
Most of the cultured mouse NG2 cells were immuno-positive to NG2 glial cell marker NG2, and a small number of cells expressed oligodendrocyte marker molecules 04 and CNPase, but no expression of neuron marker molecule Tuj1 and stem cell marker molecules Sox2 and Oct4 was detected. After 10 days of transfection of NG2 cells with hNG2 transcription factor-IRES-GFP lentivirus, the morphology of NG2 cells and the marker molecule Tuj1 of neurons were detected. After 21 days of infection with lentivirus, the marker molecules NeuN and MAP2 of mature neurons were detected at the same time, and whether the cells with neuron morphology and positive markers could produce action potential by electrophysiological recording. If spontaneous postsynaptic current could be recorded, it means that these neurons could form functional synapses.
(3) Neurons Induced by NG2 Cells can Survive after Transplantation into Vivo
Whether the transdifferentiated neurons induced in vitro can survive and function in vivo is the key to whether they can be used for disease treatment. Two weeks after the neurons induced by NG2 cells are transplanted into the cerebral cortex, the immunohistochemical experiment of the transcription factor needs to observe whether the transplanted cells can attach to the edge of the cortex, and detect whether the cells form neurites and extend deeper into the cortex. At the same time, immunofluorescence co-localization test was used to detect whether the transplanted cells expressed neuronal marker molecules Tuj1, NeuN and MAP2.
It should be noted that, except for NG2 promoter, other glial cell-specific promoters can achieve similar trans-differentiation functions. Although there are slight differences in transformation efficiency, for uniform screening, the in vitro model of glial cell trans-differentiation is uniformly carried out under the same vector type and the same promoter.
In Vivo Model of Glial Cell Transdifferentiation
(1) Construction of Adeno-Associated Virus Plasmid and Virus Infection
The GFAP promoter was cloned on the vector template of AAV-FLEX-Arch-GFP (Addgene, #22222) to replace the CAG promoter and retain the CMV enhancer. The AAV-mCherry plasmid (control group) was obtained after replacing GFP with the mCherry coding frame. The transcription factor was cloned into the AAV-mCherry plasmid to obtain the AAV-mNeurog2/mCherry plasmid. The target gene can specifically target astrocytes under the action of GFAP promoter.
(2) Astrocytes Differentiate into Neurons
The virus AAV-mCherry or AAV-transcription factor/mCherry was injected into one side of the tectum of adult wild-type mice, and then the brain tissue samples were collected at different time points. On the 3rd and 30th day of virus injection, observe whether the mCherry of control virus AAV-mCherry and mice with virus AAV-transcription factor/mCherry co-located with NeuN. In order to prove that the induced neurons are functional and active neurons, physiological recording of the midbrain electroencephalogram (MEG) of AAV virus infection was performed. Record the inward Na+current and outward K+current in the voltage clamp mode, count the proportion of recorded cell action potential and postsynaptic currents, and observe whether the postsynaptic current signal disappears and whether the post-synaptic current signal appears after elution through the blocker NBQX to determine whether the induced neurons integrate into the neural circuit to establish synaptic connection, To determine whether it is a functional neuron.
The AAV virus is carried out with reference to the mouse brain atlas. After the injection of the virus, the midbrain and spinal cord of the back were collected at different time points for immunocoloration or brain slice recording. The injection concentration and speed of intact spinal cord and injured spinal cord virus are consistent with the injection volume per needle and the brain area. The injection is conducted in the spinal cord at an angle of 30°.
Nerve Injury Repair Model
(1) Spinal Cord Injury and Virus Transfection
The T8-T10 model of complete spinal cord injury in mice was constructed (referring to the method of McDonough A, Monterubio A, Arizona J, et al. Calibrated Forceps Model of Spinal Cord Compression Injury. Jove-Journal of Visualized Experiments 2015.). AAV-mCherry virus and AAV-transcription factor/mCherry were injected into both sides of the injured spinal cord immediately after injury. Observe whether mCherry and NeuN are co-located 3 days after virus injection and 30 days after virus injection.
(2) Repair Detection of Spinal Cord Injury
After thoracic spinal cord injury, the loss of sensory afferent leads to the weakening of the inhibitory effect of the descending inhibitory system of the brain stem, which leads to the over-sensitivity of the tail to external stimuli. We used the tail flick experiment model to test the sensory ability of mice by measuring the delay time of the tail response of two groups of mice under 48° C. and 52° C. thermal stimulation. The motor function of mice was scored according to the BMS standard. For the test method, refer to Basso Mouse Scale for localization detection differences in recovery after final core adjustment in five common mouse strains J Neurotrauma, 2006. 23 (5): p. 635-59.
Glioma Model
The mice used for glioma model transplantation were NOD-scid mice of seven weeks. Provide human glioma cells with 0.25% trypsin digestion and induction for 3 days or without induction. Centrifuge and remove the supernatant to make the cell density after concentration about 2.5×105 cells/μL. Transplant brain striatum of each mouse 2 μL (5 in total×105 cells). Histochemistry was performed 3 weeks after transplantation or virus was injected one week after transplantation, followed by immunohistochemistry.
First of all, we used the model of glial cell trans-differentiation in vitro to conduct preliminary screening, and obtained a batch of transcription factors that can induce glial cell trans-differentiation into neurons. The coding sequence and conversion efficiency of the transcription factors used are shown in Table 1.
In vitro trans-differentiation efficiency %=(the number of virus-infected fluorescence-positive cells with positive neuronal marker Tuj1 and spontaneous postsynaptic current detected by electrophysiology/the total number of virus-infected fluorescence-positive cells)×100%, at least 100 transdifferentiated cells with Tuj1 positive and spontaneous postsynaptic current can be detected for each transcription factor on average.
Both human and mouse derived transcription factors have the ability to differentiate glial cells into neurons in vitro.
In further research, we also found that for human Asc11 protein, if the five conserved serine-proline (SP) phosphorylation sites (located at positions 93, 190, 194, 207 and 223 of the protein sequence) of the protein sequence were mutated into alanine-proline (AP) (enhanced Asc11 (SA-hAsc11), and the protein sequence SEQ ID NO: 41), the transformation efficiency could be further improved to 85.5%.
According to the in vivo model of glial cell trans-differentiation, we tried to use the selected transcription factors in Example 1 to induce glial cells in the dorsal midbrain, as shown in the following table (Table 2). Different transcription factors showed significantly different transformation efficiency.
The efficiency of trans-differentiation in vivo is characterized by the proportion of the occurrence of neuronal co-localization. The efficiency of trans-differentiation in vivo %=(the number of virus-infected fluorescent positive cells with positive neuronal marker NeuN and spontaneous postsynaptic current can be detected by electrophysiology/the total number of virus-infected fluorescent positive cells)×100%, at least 100 transdifferentiated cells with NeuN positive and spontaneous postsynaptic current can be detected for each transcription factor on average.
Based on the in vivo model, we further studied the expression elements of AAV expression vector in detail, and found at least three technical improvements that can significantly increase the efficiency of glial cell transformation.
(1) Insertion of VP16 Fusion Protein
VP16 is the active domain of VP16 protein from Herpes simplex virus (SEQ ID NO: 45). We cloned its gene sequence into AAV-transcription factor/mCherry plasmid to obtain AAV-VP16-transcription factor/mCherry plasmid. VP16 can be single or multiple strings. The plasmid will translate the fusion protein VP16-transcription factor, thus enhancing the function of activating gene expression of the transcription factor. The efficiency of neurons induced by AAV-VP16-transcription factor/mCherry is significantly higher, and the induction speed is faster (see Table 3).
(2) Promoter Shortening
After changing the human hGFAP promoter 2.2 kb (SEQ ID NO: 42) to 683 bp (SEQ ID NO: 43), we found that the modified promoter did not affect the specificity of targeted astrocytes, at the same time, it improved the packaging efficiency of AAV, reduced the empty shell rate of virus packaging, and obtained a higher and purer AAV titer. When induced in vivo, Short-hGFAP-AAV transcription factor/mCherry can improve the efficiency of virus transfection, reduce the number of cell death, and make the induction process safer (see Table 3).
(3) Enhancer Insertion
We inserted the enhancer (SEQ ID NO: 46) of simian vacuolating virus 40 SV40 into the hGFAP-AAV transcription factor/mCherry plasmid to obtain SV40-hGFAP-AAV transcription factor/mCherry. The enhancer of SV40 can greatly enhance the activity of hGFAP promoter, so that the target gene can be efficiently expressed in vivo, thus improving the efficiency of neuron induction (see Table 3).
The above three methods of enhancing expression can be used alone or in combination or at the same time, which can improve the inducing efficiency of the transcription factors described in this embodiment (taking human Asc11 as an example, see Table 3).
Similarly, for other transcription factors, any of the above three technical solutions can significantly improve the transformation efficiency or AAV titer. Table 4 shows the average transformation efficiency of other transcription factors after using the above transformation strategies.
According to the trans-differentiation model of glial cells in vitro and in vivo, and in combination with the vector transformation strategy described in Example 2, we first expand the selected transcription factors into random pairwise combinations. Among them, different transcription factors can be expressed simultaneously in the same vector or separately in different expression vectors. The expression ratio in the following table is the molar concentration ratio of the functional protein expressed in the actual study. In NeuroD1, Brn2, Gsx1, Tbr1, Dlx2, Ptf1a, Pax6, Otx2 transcription factors, we unexpectedly obtained several groups of single transcription factors with low efficiency, but when combined, they can significantly improve the efficiency of transcription factors. Moreover, the closer the molar concentration ratio of the expressed functional protein is, the higher the conversion efficiency obtained (see Table 5).
Taking NeuroD1 and Brn2 as examples, the trans-differentiation efficiency of single use was 42.30% and 8.70% respectively (Table 1), while the trans-differentiation efficiency of combined use (1:1) was 76.2%, with synergistic effect. Similarly, Gsx1+Tbr1, Dlx2+Ptf1a, Pax6+Otx2 can also synergistically significantly improve the efficiency of trans-differentiation.
In the study, we also found that Asc11 and Ngn2 are two key transcription factors. When combined with any of the above transcription factors or transcription factors, they can achieve significant enhancement of transcription efficiency, and achieve the function of superposition or synergy (see Tables 6 and 7).
Spinal cord injury (SCI) is a kind of central nervous system injury disease, accompanied by the death of spinal cord neurons and the formation of glial scar. In vivo neuronal reprogramming converts astrocytes into neurons, which may alleviate the damage caused by SCI, and is expected to become a new treatment method.
According to the nerve injury repair model, we found that the transcription factor or combination of transcription factors described in Examples 1-3 with conversion efficiency of more than 50% have the ability to induce glial cells at the injured site to obtain electrophysiological characteristics, and can accept external signal input. According to the detection model of spinal cord injury. We found that these transcription factor reprogramming neurons are very helpful for the recovery of sensory function and motor function of mice with spinal cord injury, especially the transcription factor or combination of transcription factors with conversion efficiency of more than 75% described in Examples 1-3. The preferred transcription factors and their combinations are shown in Table 8.
On the basis of obtaining the transcription factors and their combinations as shown in Example 1-3, we also explored the application of transcription factors or combinations of transcription factors with high conversion efficiency to promote the trans-differentiation of glioma cells into neurons. The implementation scheme is similar to the model of glioblast trans-differentiation in vivo or in vitro. Taking the factor combination of NeuroD1 and Brn2 as an example, the specific implementation is as follows:
(1) Plasmid Construction and Virus Infection
On the vector template of FUGW-IRES-EGFP (refer to the document Efficient transfer, integration, and sustained long term expression of the transgene in adult rat brain injected with a lentiviral vector. Proc Natl Acad Sci USA 93:11382-11388 for vector information), the polynucleotide functional fragment was constructed onto the lentivirus vector to generate lentivirus plasmid carrying the polynucleotide functional fragment. In one embodiment, a human NeuroD1 transcription factor fragment (SEQ ID NO: 3) was constructed onto the lentivirus vector to generate hNeuroD1 IRES EGFP lentivirus plasmid. The packaging of lentivirus refers to the literature “Production and purification of lentivirus vectors” (Tiscornia, G., Singer, O. & Verma, I. M. Nat. Protocol. 1, 241-245 (2006)).
The lentivirus was added to the human glioma cells after 24 hours of plate culture, and the culture medium was changed after 24 hours of infection: DMEM/F12, B27, Glutamax and penicillin/streptomycin. After 6-7 days of infection, brain-derived neurotrophic factor (BDNF; PeproTech, 20 ng/ml) was added to the culture medium every three days.
(2) NeuroD1 Converts Glioma Cells into Neurons
After the cultured human glioma cell U251 was infected with hNeuroD1-IRES-EGFP lentivirus for 14 days, we found that part of Tuj1 positive cells appeared and showed the morphology of neurons (
(3) Co-Expression of NeuroD1 and Brn2 Improves the Efficiency of Glioma Cells to Differentiate into Neurons
Although NeuroD1 alone can transform glioma cells into neurons, its induction efficiency is not very high. In order to improve the induction efficiency, we tested other transcription factors, and found that NeuroD1 and Brn2 (SEQ ID NO: 7) together could very efficiently transform glioma cell U251 into neurons, and the cells showed the morphology of mature neurons (
(4) Molecular Expression Properties of Glioma Cells Transdifferentiated Neurons
21 days after glioma cell U251 was infected with lentivirus hNeuroD1-IRES-EGFP and hBrn2-IRES-EGFP, cellular immunofluorescence showed that the induced neurons expressed the marker molecules MAP2 (
(5) Electrophysiological Properties of Glioma Transdifferentiated Neurons
After glioma cell U251 was infected with lentivirus hNeuroD1-IRES-EGFP and hBrn2-IRES-EGFP for 28 days, electrophysiological records showed that the induced neurons could emit multiple action potentials (
(6) NeuroD1 and Brn2 Induced Trans-Differentiation LED to the Withdrawal of Glioma Cells from the Cell Cycle
Neuron cells are cells that withdraw from the cell cycle and no longer divide. NeuroD1 and Brn2 can induce glioma cells into neurons, which will cause glioma cells to withdraw from the cell cycle. To further confirm this point, we labeled BrdU at different time periods (the 1st, 3rd and 5th days) of lentivirus infection, and then immunocytochemical analysis was performed 2 hours after labeling (
(7) NeuroD1 and Brn2 Induced Trans-Differentiation Inhibits the Proliferation of Glioma Cells
Further, we performed immunofluorescence staining on the endogenous molecular marker Ki67 as a proliferating cell, and found that the number of Ki67 positive glioma cells expressed by NeuroD1 and Brn2 lentivirus was significantly reduced (
These results together show that NeuroD1 and Brn2 can induce malignant proliferating glioma cells into terminally differentiated neurons, and cause glioma cells to withdraw from the cell cycle, thus no longer proliferate.
(8) The Tumorigenicity of Glioma Cells Expressing NeuroD1 and Brn2 was Significantly Reduced In Vivo
Because NeuroD1 and Brn2 can induce glioma cells cultured in vitro into neurons and cause glioma cells to withdraw from the cell cycle, the ability of these induced glioma cells to generate tumors in vivo will also be affected. We have carried out an in situ tumor cell transplantation experiment. The human glioma cell U251 cells infected with NeuroD1 and Brn2 lentivirus for 3 days (5×105) Transplanted into the striatum of NOD-scid mice, the size of tumor tissue volume was evaluated 21 days later. The results showed that compared with the control, the tumor tissue of glioma cells infected by NeuroD1 and Brn2 lentivirus was significantly smaller, indicating that the tumorigenicity of these glioma cells was significantly reduced.
Then, we selected transcription factors or combinations of transcription factors with a transformation efficiency of more than 50% to test the trans-differentiation ability of these groups of transcription factors in glioma cells and the inhibition ability of the proliferation of glioma cells, and found that transcription factors or combinations of transcription factors with a trans-differentiation efficiency higher than 75% have the best inhibition effect on glioblast-derived tumors. The preferred transcription factors and their combinations are shown in Table 9.
On the basis of Example 5, we tried to verify the effect of transcription factors on the mouse transplanted tumor model, still taking the combination of NeuroD1 and Brn2 as an example, the specific implementation is as follows:
(1) Construction of AAV Plasmid
On the vector template of AAV-FLEX-Arch-GFP (Addgene, #22222), the fragment from human NeuroD1 (SEQ ID No.: 3) was constructed onto the vector to obtain AAV-hNeuroD1-P2A-GFP. P2A is a self-cleaving polypeptide, which can achieve high co-expression of hNeuroD1 and GFP. The CDS (SEQ ID No.: 7) fragment from human Brn2 gene was constructed onto the vector to obtain AAV-hBrn2-P2A-GFP.
(2) AAV Vector of NeuroD1 and Brn2 Inhibits the Growth of Glioma Cells in the Brain
In order to confirm whether NeuroD1 and Brn2 induced reprogramming has the ability to treat glioma cells, we first carried out intracerebral transplantation of glioma cells (5×105). Seven days after transplantation, we injected the AAV vector of NeuroD1 and Brn2 in situ. After 30 days of virus injection, immunohistochemistry analysis showed that the cells infected with the virus expressed neural marker molecule Tuj1, showing the morphology of neurons. At the same time, the volume of tumor also decreased significantly. More importantly, the life span of mice injected with NeuroD1 and Brn2 AAV virus was significantly prolonged.
Other transcription factors or combinations of transcription factors with trans-differentiation efficiency higher than 75% have also been observed in the glioma inhibition model.
(3) AAV Vector Expressing NeuroD1 and Brn2 Inhibits the Growth of Tumor Cells in Human Glioma U87 BALB/CA-Nu Mice Heterotopic Inoculation Model
Cultured human U87 human glioma cells were inoculated into the armpit of nude mice during the logarithmic growth phase and passed through two passages. The tumor-bearing mice were taken under aseptic conditions, cut the tumor into small pieces of rice grains with uniform size, and inoculated subcutaneously into the armpit of nude mice with the insertion needle. After the tumor grew to about 100 mm3, the nude mice with appropriate tumor were randomly divided into groups, and the drug administration began after grouping. All samples were dissolved with PBS, and the intratumoral injection volume was 50 μL/tumor, measure the length and width of the tumor every 3 days, and calculate the tumor volume with the following formula:
Volume=(length×Width2)/2
The tumor inhibition rate is calculated according to the following formula:
Tumor inhibition rate %=(V model group−V administration group)/V model group×100%
The animals were killed in the later stage, and the tumor was weighed for biochemical and molecular detection. The results showed that the expression of AAV-mediated reprogramming factor significantly reduced the tumor volume (
In addition to the lentivirus vector and adeno-associated virus vector described in the above embodiment, other types of delivery systems can also achieve similar functions. In this embodiment, the adenovirus vector type 5 expressing NeuroD1 and Brn2 can also inhibit the growth of human glioma U87 BALB/CA-nu mice heterotopic implantation model tumor cells.
Because adeno-associated virus can not replicate independently in vivo, we designed adenovirus type 5 vector to express reprogramming factors efficiently and rapidly. With the specific amplification of adenovirus type 5 in tumor cells, we can achieve the effect of in vivo trans-differentiation therapy to control the recurrence of glioma.
On the vector template of Adeno-Cas9 (Addgene, #64072), the CDS (SEQ ID No.: 7) fragment derived from human NeuroD1 (SEQ ID No.: 3) and human Brn2 gene was constructed on the vector through the Age I/Spe I double restriction site to obtain Ad5-hNeuroD1-P2A-hBrn2 (Ad5-AN). P2A is a self-cleaving polypeptide, which can achieve high co-expression of hNeuroD1 and hBrn2.
We used the heterotopic inoculation model of human glioma U87 BALB/CA-nu mice. At the logarithmic growth stage, the U87 human glioma cells in culture were inoculated into the armpit of nude mice, and when the tumor grew to about 100 mm 3, the nude mice with appropriate tumor mass were randomly divided into groups, and the drug was administered after grouping. The control group was PBS group, and the dose of Ad5-AN-low group was 3×108 PFU Ad5-vector-high group dose 1×109 PFU, administered once every two days, for five consecutive times. The volume of tumor was measured and calculated every 3 days, and the animals were killed in the later stage, and the tumor was weighed for biochemical and molecular detection.
The results showed that compared with the control PBS group, the tumor volume of Ad5-AN-low group decreased by 32.25%, and that of Ad5-AN-high group decreased by 67.49% (
We also use exosomes (GBM-Exo) derived from mesenchymal cells or glioblastoma cells. The exosomes were extracted from the supernatant of cell culture by density gradient centrifugation and molecular exclusion separation, and the expression of exosome-marker protein CD63 was identified by Western blot, the shape characteristics and particle size of exosomes were detected by transmission electron microscopy and dynamic light scattering, and the concentration of exosomes was detected by BCA protein quantitative method.
For glioblastoma, Asc11-mRNA (NCBI Reference Sequence: NM_004316.4) or other transcription factor combinations described in the present invention are introduced into the exocrine body through endogenous expression or exogenous introduction. Exocrine drugs derived from glioblastoma will specifically infect human glioblastoma cell lines U251 and U87. In the logarithmic growth phase of cells, it can be observed that the efficiency of exocrine drugs inducing human glioblastoma cell lines U251 and U87 into neurons can change with the concentration gradient of exocrine drugs, and the rate of related tumor cell proliferation is also proportional to the efficiency of neuron induction.
All documents mentioned in the present invention are cited as references in this application, just as each document is cited separately as a reference. In addition, it should be understood that after reading the above lectures of the invention, those skilled in the art can make various changes or modifications to the invention, and these equivalent forms also fall within the scope of the claims attached to the application.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202010934192.9 | Sep 2020 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/117302 | 9/8/2021 | WO |
