Patent Application
20200010802
The present invention pertains to the field of tissue engineering. In particular, the present invention concern to a method for preparing a supplement from mesenchymal cell cultures of Wharton's jelly and uses of same.
The cutaneous trauma cause diverse conditions that put at risk the health of patient, between these conditions are included dehydration, loss of electrolytes and proteins in the wound site, at the same time that the wound remains exposed to bacterial infections. In the last decades diverse methods has been developed, allowing replacement of the main components of skin, epidermis, and dermis, with biological equivalents produced in vitro.
Between the methods employed for preparing epidermal equivalents, the most common corresponds to describe in the 70's decade by Rheinwald James G and Green (Serial cultivation of strains of human epidermal keratinocytes: the formation of keratinizing colonies from single cells, 1975). The method of Rheinwald and Green have a high reliability, studies have been performed (Benathan and Labidi-Ubaldi, Substitus epidermiques et dermo-epidermiques vivants pour le traitement des grands brülés, 1998) where from 65 performed preparations, only anomalies were detected in four cases in the dermic equivalents prepared, two of those cases corresponded to cultures in which was poor stratification, in the other two the cells revealed signs of apoptosis.
In the clinic practice, the method of Rheinwald and Green presents difficulties such as the high fragility from epidermal grafts cultivated in absence from dermal equivalents and high cost from transplants (Miguel Concha, Production from autologous dermo-epidermal equivalents for treatment of great burns and keloid scars, 2002). On the other hand, the inclusion of elements from animal origin in the process of elaboration from Rheinwald and Green for epidermal equivalents can attend with the persistence of mouse fibroblasts, as well as residuals of bovine fetal serum in the finalized epidermal equivalent (Cairns B A, Xenogenic mouse fibroblast persists in human cultured epidermal grafts: a possible mechanism of graft lost, 1995), which can cause the rejection of it because the immune response from patient.
To build epidermal equivalents both cutaneous and/or dermal, cells 3T3 have been used to induce the proliferation of keratinocytes in culture. The cells 3T3 are mouse embrionary fibroblasts, serving as feeder cells (humans or animals) or “nurses” (Rheinwald J G, Green H., Serial cultivation of strains of human epidermal keratinocytes: the formation of keratinizing colonies from single cells, 1975). This method has been widely used to grow keratinocytes.
Briefly, the previous method comprises to grow the obtained cells from a biopsy in presence of irradiated cells 3T3, subsequently; the culture of keratinocytes washes and collects. The previous methodology has allowed to obtain large quantities of keratinocytes, in order to construct epidermal equivalents including cutaneous equivalents or dermal equivalents used to treat patients with second or third degree burns (Llames S, Garcia E, Garcia V, del Rio M, Larcher F, Jorcano J L, et al. Clinical results of an autologous engineered skin, 2006).
On the other hand, there is evidence that the use of mesenchymal cells applied directly in wounds promotes the recovery by an indirect mechanism, delivering diverse molecules that may have a therapeutic effect, for example, growth factors and other cytokines, while the mesenchymal cells can differentiate to fibroblasts (Chui-Yee Fong, Human Wharton's Jelly Stem Cells and Its Conditioned Medium Enhace Healing of Excisional and Diabetic Wounds, 2014). The mesenchymal cells obtained from Wharton's jelly secrete different factors, which can induce the proliferation of keratinocytes and fibroblasts in culture. The use of conditioned media to grow several cell types has gained ground strongly, in which it has been observed that resident cells of a tissue can modulate the secretory activity from mesenchymal cells and these in turn induce the differentiation to cells from tissue in question (Vidya Gopakumari, Nivedita Chatterjee, Sowmya Parameswarani, Subramanian Nirmala and Subramanian Krishnakumar, 2016). However, a history in the production of use epidermal equivalents from does not exists, whether cutaneous and/or dermal so that promotes the delivery of growth factors necessary to stimulate the cellular proliferation in vitro from several cells of cutaneous system, to perform epidermal equivalents whether cutaneous and/or dermal.
In the state of the art already disclosed alternative methods for preparing epidermal equivalents to avoid the use of animal elements, for example using autologous or allogenic human fibroblasts to promote the growth and differentiation of keratinocytes during the elaboration from cutaneous equivalent (Mazlyzam, Reconstruction of living bilayer human skin equivalent utilizing human fibrin as a scaffold, 2007). Even though these methods avoid the risk of allergic reactions to animal components (zoonosis), do not reduce significantly the cost to patient. Then, there is a need to have alternative methods for preparing epidermal equivalents offering different advantages.
Here is described a method for preparing a supplement that when used in the elaboration of epidermal equivalents, permits the removal from risk of zoonosis and offers a decrease in the manufacturing costs of same.
Additionally, the supplement obtained by the method of present invention can be used as additive in the cell cultures from cutaneous system, to elaborate a cell suspension of fibroblasts and to use in the treatment of diseases, defects, cutaneous disorders as result from cutaneous aging.
The application of cultivated fibroblasts using the supplement obtained by the method developed increases the cellular activation, promoting an increase from mechanical stress in the extracellular matrix, inducing an elongation from fibroblasts and the stimulation in the collagen synthesis, release of growth factors, inhibition from metalloproteinase secretion, and increasing the secretion from inhibitor factors of the same.
The supplement is prepared from the supernatant of mesenchymal cell cultures obtained from Wharton's jelly cultivated in specific conditions. The supplement includes growth factors necessary to favor and increases the cellular proliferation in vitro for several cells from cutaneous system.
The invention is illustrated below, without limitation, with reference to described examples and figures:
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The present invention is related with the production of a supplement from mesenchymal cell cultures of Wharton's jelly and its use in the development of cell cultures from cutaneous system in vitro.
As used in the present invention, the cells of cutaneous system comprise fibroblasts, keratinocytes, dendritic cells, monocytes or combinations of the same, which can be cultivated in an isolated manner. The supplement obtained by the method in the present invention can be used in the expansion of cutaneous cell populations or incorporated in culture mediums for the same, independently from intended use of the cells.
In a first aspect, the present invention provides a method to obtain a supplement from mesenchymal cells of Wharton's jelly.
In a modality, the method to obtain the supplement comprises:
a) Cultivate mesenchymal cells of Wharton's jelly in a culture medium suitable with growth factors to reach a suitable confluence;
b) Harvest the cultivated cells from step a) and cultivate in a suitable medium, without growth factors;
c) Collect the conditioned medium from step b);
d) Repeat the steps a) and b), at least once; and
e) Concentrate the conditioned medium and sterilize by filtration.
The mesenchymal cells of Wharton's jelly used in the present invention are obtained from collect a fragment of umbilical cord, under aseptic conditions, subsequently the size of umbilical cord is reduced by a medical and enzymatic treatment.
As used in the present invention, “Cultivate mesenchymal cells of Wharton's jelly” refers to cultivate treated fragments from umbilical cord in a suitable culture medium to reach a suitable confluence.
As used in the present invention “Harvest the cultivated cells” refers to separate the previous cultivated cells from culture medium by an enzymatic treatment; wash the previous cultivated cells; and seeds the previous cultivated cells in a new suitable culture medium during a determined time, preferably 48 hours. As used in the present invention, “harvest the cultivated cells” is equivalent to “step”.
The cell culture in accordance with the steps a) and b), is repeated preferably at least once, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 6 times, at least 7 times, at least 8 times, at least 9 times.
As used in the present invention, “the conditioned medium” refers to culture medium obtained from seed or steps, that is found free of cells. Besides contain the proper components of their formulation, contains the secretion products (proteins, hormones, growth factors, cytokines, and signaling molecules) that are produced and delivered by the cells in question during its culture.
As used in the present invention, the term “supplement” corresponds to the conditioned medium by the mesenchymal cells concentrated and sterilized. The supplement can be used in a culture medium.
In a preferred modality, the supplement from present invention comprises several cytokines, for example, the compounds Actine, Annexin A1, Amyloid beta A4, ATP synthase sub-unity-B, Cadherin 2, CD44, Collagen chain alpha-1(VIII), EGF, derived factor of epithelium pigmentary, Fibronectin, FGF-2, Inhibin chain Beta, Integrin B1, Interleukin 6, ILGF-bp4, ILGF-bp7, Keratin 2, Laminar sub-unity Alpha-2, Lipoprotein lipase, MAPK1, Myosin 9, Moesin, M-CSF, MPI-1, PI-2, Nexin derived of glia, NDP-kA, NDP-kB, PAI-1, PDGF sub-unity A, Peroxyredoxin 1, Peroxyredoxin 2, Complementary protein 5 of reparation to XR, protein ih-h3 induced by TGFB, Purine nucleoside phosphorilase, Sulfhydryl oxidase, SPARE, Substrate 1 from botulinum toxin related to Ras, Substrate 2 from botulinum toxin related to Ras, Thrombospondin, Tropomyosin alpha 1, TGFB, TGFB-R1, TGFB-R2, VEGF A, and Vinculin.
The term “mesenchymal cells of Wharton's jelly” refers to multi-potential cells from mesoderm obtained from umbilical cord.
The term “confluence” refers to the number of cells in a cell culture and is referred to grade in which the cells cover the surface of a solid culture medium or volume of a cellular culture. The confluence is measured in % with respect to occupied total volume.
As described in the present invention, the term “suitable confluence” refers to a suitable percentage (%) to be used in a process, for example, in the elaboration from supplement, elaboration from dermal equivalent or cutaneous equivalent in accordance with the present invention. Preferably, such percentage is greater than 60%, more preferably, is greater than 80%.
The term “suitable culture medium” refers to a culture medium for mesenchymal cells, for example, a DMEM-F12 medium (DMEM 50%-F12 50%) supplemented with 10% bovine fetal serum 10% and antibiotics. The suitable culture medium can be supplemented with growth factors, for example, the epidermal growth factor (EGF) and basic factor of fibroblasts development (FGFb).
In other aspect, the present invention provides methods to obtain an epidermal equivalent using the supplement from present invention. As used in the present invention, the epidermal equivalents refer to epithelial cells laminates grown over a culture. The epidermal equivalents are useful to be applied in patients with second degree superficial burns or with cutaneous chronic ulcers of different etiology. The epidermal equivalents can be dermal or cutaneous equivalents.
As used in the present invention, the term “dermal equivalent” refers to a tissue construed by tissue engineering comprising a cellular layer of fibroblasts and an extracellular matrix organized similarly to dermal tissue in the skin. The fibroblasts are located placed within a scaffold of natural, synthetic or composite biomaterials.
As used in the present invention, the term “cutaneous equivalent” refers to a tissue constructed by tissue engineering comprising an internal layer and an external layer, in which the internal layer comprises the dermal complex, and the external layer comprises the epidermal complex constituted by a monolayer of keratinocytes. Both layers are organized similarly to dermis and epidermis in the skin, respectively. In a modality, the external layer consists of stratified plane epithelium with stratum corneum. The epidermal equivalent is located placed over the dermal equivalent constructed with natural, synthetic or composite biomaterials.
In a preferred modality, the method to obtain the dermal equivalent comprises:
a) Cultivate autologous or allogenic fibroblasts in a culture medium containing the supplement from present invention to obtain a suitable confluence; and
b) Produce the dermic equivalent.
The fibroblasts used in the method to obtain the dermal equivalent can be obtained from autologous or allogenic cells from cutaneous system, from which the fibroblasts of dermis are separated by an enzymatic treatment.
As used in the present invention “cultivate fibroblasts” refers to maintain fibroblasts in a culture medium comprising the supplement from present invention to reach a suitable confluence; separate previous cultivated cells from culture medium by an enzymatic treatment; wash the previous cultivated cells; and reseeds the cells in a culture medium comprising the supplement from present invention to reach a suitable confluence for the construction from dermic equivalent. The supplement from present invention is used in a concentration from of 5% to 50% with respect to total volume form culture medium.
As used in the present invention, “Produce the dermic equivalent” refers to place the fibroblasts cultivated previously in a solution containing fibrinogen and prothrombin in presence of antifibrinolytics, sodium chloride and calcium chloride, to form a cellular suspension; place the cellular suspension in a container and incubate to its gelation; and place the gel over a scaffold of natural, synthetic or composite biomaterials with adhesive biocompatible.
In a preferred modality, the method to obtain the cutaneous equivalent comprises:
a) Cultivate autologous or allogenic keratinocytes in a culture medium containing the supplement from present invention to obtain a suitable confluence; and
b) Produce the cutaneous equivalent.
As used in the present invention “cultivate keratinocytes” refers to cultivate keratinocytes in a culture medium comprising the supplement from present invention to reach a suitable confluence; separate previous cultivated cells from culture medium by an enzymatic treatment; wash the previous cultivated cells; and reseeds the cells in a culture medium comprising the supplement from present invention to reach a suitable confluence, necessary to the construction the cutaneous equivalent. The supplement from present invention is used in a concentration of 5% al 50% with respect to total volume from culture medium.
As used in the present invention “Produce the cutaneous equivalent” refers to seed and cultivate the keratinocytes previously cultivated over gelled fibroblasts in a culture medium added with the supplement from present invention to reach the suitable confluence; and place over a scaffold of natural, synthetic or composite biomaterials with adhesive biocompatible. In a preferred modality, the fibroblasts used to elaborate the cutaneous equivalent, are obtained according to the elaboration method of dermic equivalent. The supplement from present invention is used in a concentration of 5% to 50% with respect to total volume from culture medium.
The term “autologous system” comprises an epithelial and dermal cells system obtained from the same person to which the tissue will be grafted. The term “allogenic system” comprises epithelial and dermic cells obtained from a different person to which the tissue will be grafted.
In other aspect, the present invention is related with the use of dermic equivalent, obtained by the method from present invention, to treat diseases, defects, dermal disorders, or wounds. The dermal equivalents from present invention are useful to induce in the patient a regeneration from conjunctive tissue, to subsequently promote the reepithelialization. The use of dermal equivalents from present invention consists in apply directly the dermal equivalent over the wound bed at least once a week to regenerate the dermal and epidermal tissues from patient, what is achieved un a period from 2 to 14 weeks treatment, preferably 4 to 8 weeks.
The candidates to receive the treatment with dermal equivalents comprise patients presenting diseases, defects, dermal disorders, or wounds, for example, ulcers, chronic wounds, vascular, arterial, venous, and lymphatic, of decubitus or diabetic foot. The patient must be free of infection in wound and in case of being diabetic with the controlled glycaemia. To apply the dermic equivalent, the wound must be washing by the use of antiseptic solution to subsequently debridement from lesion. After preparing the area of lesion, the dermal equivalent is directly implanted over the injured tissue, subsequently is covered with an insulating bandages to prevent its detachment, keeping in that way by a sufficient time to reach the closure of the wound.
In other aspect, the present invention is related with the use of the cutaneous equivalent, obtained by the method from present invention, in the treatment from diseases, dermal defects, cutaneous disorders or wounds when the thickness from condition is partial or with an extension requiring graft. The use from cutaneous equivalent is applicable for example, when the dermal defect is a nevus, tattoo, hypertrophic scar, keloid or burn scar or of a size large enough to be surgically removed. The use from cutaneous equivalent can be applied for the case of second or third degree burns from a size large enough to be surgically removed.
The implantation from cutaneous equivalent is performed by a surgical procedure, in which the cutaneous equivalent is placed as a graft immediately after of retirement from affected tissue, fixing by using sutures, surgical staples ora suitable adhesive, to subsequently cover with un an insulating bandage to avoid its detachment. Once implanted the cutaneous equivalent, the affected zone remains covered by a sufficient time to reach the closure of the wound.
In other modality, a method to manufacture a cellular suspension of fibroblasts is provided. The method comprises:
a) Cultivate fibroblasts, in a culture medium comprising the supplement from present invention to reach a suitable confluence; e
b) Incorporate the fibroblasts from step a) in a solution of autologous blood serum.
In other modality, the obtained supplement from developed method or cellular suspension of fibroblasts described in the above paragraph, can be used to favor the growth and activation in vitro from cells of cutaneous system which can be inactive by age, for example in the skin of adult patients with fine, moderate to deep, or deep wrinkles; loss of dermal tone and subcutaneous tissue; injuries in the skin such as atrophic scares as acne marks grade I (macular), II (mild), Ill (moderate), and IV (serious) and injuries of cutaneous caused by red or white stretch marks; pigmentary injuries from type solar or senil lentigo and simple lentigo, melasma and melanodermias from different etiology; injuries of acne; photo-aging severe classified with Fiztpatrick's scale from I, II, or III, in Glogau's scale fom 1, 2, 3, or 4 and in SCINEXA's scale from 0, 1, 2, or 3 characterized in that loss of elasticity and tissue tone, this because fibroblasts gradually losing the capacity to synthetize some elements from dermic extracellular matrix, so that can be obtain autologous fibroblasts from such patients and cultivate in presence from supplement elaborated according with the developed method in a concentration from between 5% to 50%, 5% to 50% with respect to total volume from culture medium, promoting a reactivation from cells restoring its synthesis and secretion capacities of dermic matrix elements so they can re-implanted by intradermal injections in areas with major damage by photo-aging.
The examples presented below have as their sole object illustrate and demonstrate some modalities of the invention. The exemplified modalities does not consider as !imitative from present invention. As a technical in the art can recognize, can be perform modifications and variations to modalities described here without alter the essence of the invention.
The conditioned medium was obtained from following procedure:
a) Collect, under aseptic conditions, a fragment of between 10 to 15 cm of umbilical cord;
b) Immerse the umbilical cord in a tube Corning of 50 ml with DMEM medium, supplemented with a solution 100× of antibiotics (penicillin [10,000 U/mL] and streptomycin [10,000 pg/mL]) and antifungal (fungizone [25 μg/mL]);
c) Cut up the umbilical cord in fragments of 1 cm length;
d) Incubate the fragments of umbilical cord in culture medium supplemented with the enzymes: collagenase and hyaluronidase during 30 min, promoting a partial digestion from Warthon's jelly;
e) Place the fragments of umbilical cord in culture plates with el DMEM-F12 medium (DMEM 50%-F12 50%) supplemented with 10% bovine fetal serum and antibiotics;
f) Perform the change of culture medium by a fresh medium, such as described in the step e each 48 hours. Repeat to reach confluence greater than 90%;
g) Harvest the cells by its incubation with a medium supplemented with Trypsin/EDTA;
h) Inactivate and remove the trypsin by washing and centrifugation;
i) Harvest the obtained cells of the harvest in a proportion from up 1 in 10 in new culture containers such as expands the cellular colony;
j) Cultivate the cells in culture containers in a culture medium of DMEM supplemented with factor for epidermal growth (EGF), basic factor of fibroblasts growth (FGFb), bovine fetal serum and antibiotics and cultivate to reach a confluence from 90%;
k) Wash the cultivated cells from step j) tree times with culture medium DMEM not supplemented to remove the growth factors exogenously added and maintain in culture with DMEM not supplemented during 48 hours;
l) Once elapsed 48 hrs, collect the conditioned medium by the cells from step k); m) After collect the conditioned medium, repeat the harvest processes, inactivation of trypsin, re-seeds, wash, culture and collect of supplement from steps g), h), i), j), k) and l) to step number 6;
n) By centrifugation sediment the cellular debris suspended in each conditioned mediums collected in the step m);
o) Concentrate the conditioned medium in a concentration of 10× by centrifugation in tubes Amicon;
p) Sterilize by filtration the concentrated conditioned medium with PVDF filter of low affinity to proteins with pore size of 0.22 um;
q) Preserve the conditioned medium to its storage by ultra-freeze to −80° C.; and r) Use the conditioned medium in cultures of keratinocytes, fibroblasts and other cells from cutaneous system to induce a proliferation of the same to a concentration of between 5% and 50% diluted in culture mediums.
A dermal equivalent was produced by the following protocol:
a) Cultivate fibroblasts in suitable culture conditions added with the supplement in a concentration of between 5% and 50% diluted in culture mediums;
b) Perform the change from culture medium by fresh culture medium, each 48 hours. Repeat to reach confluence greater than 80%;
c) Harvest the cells by its incubation with a supplemented mediums with Trypsin/EDTA;
d) Inactivate and remove the trypsin by washing and centrifugation;
e) Harvest the cells obtained from harvest in a proportion from up 1 in 10 in nevus culture containers such that expands the cellular colony;
f) Incorporate the fibroblasts from step e) in an aqueous solution containing fibrinogen and prothrombin obtained from human blood plasma in presence of antifibrinolytics, sodium chloride and calcium chloride to form a cellular suspension;
g) Place the cellular suspension from step f) in a culture container and incubate up the plasm to gels;
h) Cultivate the gelled dermal equivalent in culture with conditioned mediums during 5 days changing the fresh conditioned cultured mediums fresco each 48 hrs to a concentration of between 5% and 50% diluted in culture mediums; and
i) Place over the dermal equivalent a sterile nylon mesh and adhere over the dermal equivalent with a biocompatible adhesive, as such surgical methacrylate.
A cutaneous equivalent was produced by the following procedure.
a) Collect 1 cm2 of skin of patient and transfer to a sterile tube with antiseptic solution of benzalkonium chloride or 70% ethanol and incubate during 30 seconds;
b) Apply tree consecutive washes with culture mediums supplemented with antibiotics;
c) Cut up the skin specimens in fragments of approximately 2 mm and transfer to a tube with supplemented mediums with dispase and incubate during 18 hrs to 4° C.;
d) Mechanically separate the dermis from epidermis;
e) Transfer the epidermal laminates to a tube with trypsin-EDTA and incubate during 30 minutes at 37° C. in continue agitation;
f) Collect the supernatant and place apart the dermic laminate;
g) From supernatant, obtain by centrifugation a epidermal celular suspension;
h) Use the cells obtained for the culture of keratinocytes;
i) Transfer the dermal laminate from step g) to a new tube with mediums supplemented with the collagenase enzyme and cultivate during 4 hrs at 37° C. in continue agitation to complete digestion of dermal tissue;
j) Obtain the supernatant and centrifuge to obtain a dermal celular suspension including fibroblasts;
k) Place the fibroblasts in activation and proliferation conditions in a culture mediums added with the supplement from present invention to a concentration of between 5% and 50% diluted in culture mediums and cultivate changing with the same mediums each 48 hrs to reach a confluence greater than 80%;
l) Harvest the cells by incubation with a supplemented mediums with Trypsin/EDTA;
m) Wash and centrifuge to inactivate and remove the trypsin;
n) Seed the cells obtained from harvest in a rate from up 1 in 10 in new culture containers such as to expands the cellular colony;
o) Add the keratinocytes from step d) to dermal complex from step c) to form the cutaneous equivalent;
p) Repeat the re-seed to obtain the desired cellular density to cutaneous equivalent without expand the cells beyond from step 8; and
q) Place over the cutaneous equivalent a sterile nylon mesh and adhere over the cutaneous equivalent with a biocompatible adhesive, such as surgical methacrylate.
The dermal equivalent obtained was used in the treatment of ulcers, in accordance with the following procedure.
a) Select a patient presenting ulcers of long progression, either of vascular origin, by pressure, or diabetic foot;
b) Verify that the patient be free of infection in the ulcer and in case of being diabetic, with the glycaemia controlled;
c) Wash the ulcer by the use of antiseptic solutions;
d) Debride the ulcer removing any debris of necrotic tissue;
e) Implant the dermal equivalent from area of injury directly over the ulcerated tissue;
f) Cover with an insulating bandage;
g) Maintain the bandage during seven days; and
h) Wash the wound with antiseptic solutions at least once a week, to reach the closure of the wound.
The cutaneous equivalent obtained according with the present invention was used in the treatment from patients with burns, according with the following procedure.
a) Select a patient presenting second or third degree burns in an area of the skin that in according with the clinical judgment that considers the specialist physician, have indication to apply a graft;
b) Collect an specimen of complete skin (dermis and epidermis) from patient;
c) Isolate the epidermal from dermal layer by enzymatic digestion;
d) Obtain independently keratinocytes and fibroblasts;
e) Cultivate and expand the keratinocytes and fibroblasts in presence of the conditioned medium, to obtain the cellular density necessary to construct the superficial extension required to the graft;
f) Prepare the patient suffering of second or third degree burns to a surgical procedure in which the cutaneous equivalent will implant as a graft;
g) Remove the burned tissue by an elective surgical procedure;
h) Place the cutaneous equivalent as a graft immediately after removal from burned tissue;
i) Fix the cutaneous equivalent by the use of sutures, surgical staples or a suitable adhesive;
j) Cover the cutaneous equivalent with an insulating bandage to avoid its detachment;
k) Maintain covered the zone in which the cutaneous equivalent was placed and review between the days 5 and 7 later to verify its implantation; and
l) Handle with care the implant from cutaneous equivalent and if it is necessary clean the area.
Were recruited 36 patients from which is consent was obtained to participate in the experiment, each patient was randomly assigned to treatment with the dermal equivalent generated using the supplement elaborated by the developed method or a conventional hydrocolloid dermal equivalent so that 18 patients were assigned to each treatments.
In the Table 1 the general data from patients participating in the experiment are shown including gender, age, evolution, consumption of NSAIDs, comorbidities and size from wound to each of the two compared groups. A statistical comparison from mean values is included to each considered parameter in accordance with the statistic test applied, a P value greater than 0.05 indicate the existence of statistically significant differences between both groups. As shown in the P column from Table 1, statistically significant differences do not exist between both groups for the measured parameters.
In the Table 2 the characteristics of ulcers are shown for each patients group including islands of epithelium, granulation, fibrin, exudate and pain of each from two groups compared. Same in the Table 1, a statistic comparison is included from the mean values for each considered parameter. As shown in the P column from Table 2, statistically significant differences do not exist between the characteristics from ulcers between both groups.
In the Table 3 and
In the Table 4 the average weekly cost is presented from treatment using dermal equivalents available commercially and the cost of dermal equivalent elaborated using the supplement from present invention. The average cost from weekly treatment using the developed dermal equivalent is widely less to the average cost from conventional treatments; at the same time maintain the therapeutic activity. It is noteworthy that the treatment with Oasis is of lower price; however, does not have autologous cells such as the case from described in the developed dermal equivalent in accordance with the method described in the present invention. In the case of Dermalogen, is an acellular collagen matrix obtained from skin of cadaveric donators and is equal in costs to dermal equivalent described in accordance to the developed method in the present invention, On the other hand, its manufacture method is totally different to dermal equivalent described here.
| Number | Date | Country | Kind |
|---|---|---|---|
| MX/A/2016/12375 | Sep 2016 | MX | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/MX2017/000103 | 9/25/2017 | WO | 00 |
