Method for producing dual function proteins and its derivatives

Information

  • Patent Grant
  • 11560416
  • Patent Number
    11,560,416
  • Date Filed
    Friday, April 20, 2018
    6 years ago
  • Date Issued
    Tuesday, January 24, 2023
    a year ago
Abstract
A method for producing a dual function protein includes a biologically active protein and an FGF21 mutant protein. The method allows stable production of a target protein by effectively preventing decomposition of the target protein, and thus has a high potential for commercial usage.
Description
CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No. PCT/KR2018/004599, filed Apr. 20, 2018, claiming priority to Korean Patent Application No. 10-2017-0051758, filed Apr. 21, 2017.


TECHNICAL FIELD

The present invention relates to a method for producing a dual function protein comprising a biologically active protein and a fibroblast growth factor 21 (an FGF21) mutant protein.


BACKGROUND ART

When an animal cell is used to produce a recombinant protein, there might be a problem that a specific region of the target protein may be clipped by a protease is secreted by an animal cell (host cell) to cause heterogeneity, reduction or inactivation of the recombinant protein. In addition, such clipping of the expressed protein also leads to the problem that it gets difficult to maintain “lot to lot” homogeneity during production and purification processes. For this reason, it is necessary to keep the protease at a low level or suppress the protease activity during the production of a recombinant protein.


As an alternative to solve the problem, a production method in which inhibitors against serine, cysteine, aspartic acid or aminopeptidase (such as aprotinin, bestatin, leupeptin, E-64 and pepstatin A, etc.) are added in the culture medium was proposed (see WO 1990-002175, EP 0,306,968, and U.S. Pat. No. 5,851,800). However, the use of these inhibitors in commercial production is not effective because of cytotoxicity and the need for extra efforts to prove that they have been completely removed from the final product. In addition, among conventional alternatives, a universal method applicable to all target proteins produced in host cells has not been found yet.


DISCLOSURE OF INVENTION
Technical Problem

It is an object of the present invention to provide a culture method for producing a dual function protein comprising a biologically active protein and an FGF21 mutant protein, which has improved pharmacokinetic parameters, high stability, less potential for aggregation to form a complex, and less immunogenic potential.


Solution to Problem

In accordance with one object of the present invention, there is provided a method for producing a recombinant dual function protein from a mammalian host cell transformed with an expression vector containing cDNA encoding a dual function protein or a derivative thereof, the method comprising culturing the mammalian host cell in a culture medium supplemented with dextran sulfate, wherein the dual function protein comprises a fibroblast growth factor 21 (FGF21) mutant protein; a biologically active protein, or a mutant or fragment thereof; and an Fc region of an immunoglobulin, wherein the FGF21 mutant protein comprises at least one mutation selected from the group consisting of the mutations (1) to (7) below:


(1) a substitution of amino acids at positions 98 to 101 from the N-terminus of a wild-type FGF21 protein with an amino acid sequence of EIRP (SEQ ID NO: 53);


(2) a substitution of amino acids at positions 170 to 174 from the N-terminus of a wild-type FGF21 protein with an amino acid sequence of TGLEAV (SEQ ID NO: 54);


(3) a substitution of amino acids at positions 170 to 174 from the N-terminus of a wild-type FGF21 protein with an amino acid sequence of TGLEAN (SEQ ID NO: 55);


(4) a substitution of an amino acid at position 170 from the N-terminus of a wild-type FGF21 protein with an amino acid N;


(5) a substitution of an amino acid at position 174 from the N-terminus of a wild-type FGF21 protein with an amino acid N;


(6) a substitution of an amino acid at position 180 from the N-terminus of a wild-type FGF21 protein with an amino acid E, along with one or more mutations (1) to (5) above; and


(7) a mutation of 1 to 10 amino acids for reducing immunogenicity of a wild-type FGF21 protein.


Advantageous Effects of Invention

The production method of the present invention allows stable production of a target protein by effectively preventing decomposition of the target protein.





BRIEF DESCRIPTION OF DRAWINGS


FIG. 1 is a schematic diagram showing the result of analysis of the culture supernatant by SDS-PAGE after suspension culture of a cell line expressing a dual function protein. It was found that as the culture time elapsed, other proteins smaller than the non-clipped dual function protein were expressed together.



FIG. 2 is a schematic diagram showing the result of analysis of the culture supernatant by SDS-PAGE according to storage temperature conditions after a certain time period. The culture supernatant stored at 4° C. or −20° C. showed reduced clipping of the dual function proteins as compared to that stored at 37° C. This result indicated that the clipping phenomenon of the dual function proteins was induced by the protease derived from the host cell.



FIG. 3 is a schematic diagram showing the result of analysis by SDS-PAGE after adding protease inhibitors to the culture supernatants and storing the mixtures for a certain time period at 37° C. It was found that mainly the addition of serine protease inhibitor decreased the clipping phenomenon of the dual function protein. This result indicated that the clipping phenomenon of the dual function protein was induced by the protease derived from the host cell.



FIG. 4 is the result of analysis of the culture supernatant by SDS-PAGE after a cell culture in which dextran sulfate was added to the culture medium, and the graph thereof. The effect of reducing the clipping phenomenon of the dual function protein was not observed when dextran sulfate having a weight average molecular weight of 1.6 kDa was added, whereas clipping phenomenon of the dual function protein was reduced when 500 kDa dextran sulfate was added.



FIG. 5 is a schematic diagram showing the result of analysis of the culture supernatant by SDS-PAGE after culturing with dextran sulfates having different weight average molecular weights added to the culture medium. When dextran sulfate having a weight average molecular weight of 200 kDa or more was added to the culture medium, the clipping phenomenon of the dual function protein was reduced.



FIG. 6 is the result of SDS-PAGE analysis of the culture supernatant after the culture in which dextran sulfates at various concentrations were added to the culture medium, and the graph thereof. When dextran sulfate was added at 200-1,000 mg/L, the clipping phenomenon of the dual function protein was reduced. In addition, when the culture temperature was changed to 32° C. during the culture, the clipping phenomenon of the dual function protein could be prevented more effectively.





BEST MODE FOR CARRYING OUT THE INVENTION

In accordance with one object of the present invention, there is provided a method for producing a recombinant dual function protein from a mammalian host cell transformed with an expression vector containing cDNA encoding a dual function protein or a derivative thereof, the method comprising culturing the mammalian host cell in a culture medium supplemented with dextran sulfate, wherein the dual function protein comprises a fibroblast growth factor 21 (FGF21) mutant protein; a biologically active protein, or a mutant or fragment thereof; and an Fc region of an immunoglobulin, wherein the FGF21 mutant protein comprises at least one mutation selected from the group consisting of the mutations (1) to (7) below:


(1) a substitution of amino acids at positions 98 to 101 from the N-terminus of a wild-type FGF21 protein with an amino acid sequence of EIRP (SEQ ID NO: 53) (hereinafter, “EIRP”);


(2) a substitution of amino acids at positions 170 to 174 from the N-terminus of a wild-type FGF21 protein with an amino acid sequence of TGLEAV (SEQ ID NO: 54) (hereinafter, “TGLEAV”);


(3) a substitution of amino acids at positions 170 to 174 from the N-terminus of a wild-type FGF21 protein with an amino acid sequence of TGLEAN (SEQ ID NO: 55) (hereinafter, “TGLEAN”);


(4) a substitution of an amino acid at position 170 from the N-terminus of a wild-type FGF21 protein with an amino acid N (hereinafter, “G170N”);


(5) a substitution of an amino acid at position 174 from the N-terminus of a wild-type FGF21 protein with an amino acid N (hereinafter, “G174N”);


(6) a substitution of an amino acid at position 180 from the N-terminus of a wild-type FGF21 protein with an amino acid E, along with one or more mutations (1) to (5) above (hereinafter, “A180E”); and


(7) a mutation of 1 to 10 amino acids for reducing immunogenicity of a wild-type FGF21 protein.


FGF21 Mutant Protein


The wild-type FGF21 protein, a hormone known to play an important role in glucose and lipid homeostasis, may be one derived from mammals such as humans, mice, pigs, monkeys, etc., preferably from humans. More preferably, the wild-type FGF21 protein may be the wild-type human FGF21 protein having an amino acid sequence represented by SEQ ID NO: 1.


Preferably, the mutation included in the FGF21 mutant proteins may be any one of the mutations of EIRP(SEQ ID NO: 53), TGLEAV(SEQ ID NO: 54), TGLEAN(SEQ ID NO: 55), G170N and G174N; a combination of any one of the mutations of TGLEAV(SEQ ID NO: 54), TGLEAN(SEQ ID NO: 55), G170N and G174N and the mutation of EIRP(SEQ ID NO: 53); a combination of any one of the mutations of EIRP(SEQ ID NO: 53), TGLEAV(SEQ ID NO: 54), TGLEAN(SEQ ID NO: 55), G170N and G174N and the mutation of A180E; or a combination of any one of the mutations of TGLEAV(SEQ ID NO: 54), TGLEAN(SEQ ID NO: 55), G170N and G174N, the mutation of EIRP and the mutation of A180E.


The EIRP(SEQ ID NO: 53) refers to a mutation in which LLLE(SEQ ID NO: 57), the amino acids at positions 98 to 101 from the N terminus of a wild-type FGF21 protein, is substituted with EIRP(SEQ ID NO: 53). Further, the TGLEAV(SEQ ID NO: 54) refers to a mutation in which GPSQG(SEQ ID NO: 58), the amino acids at positions 170 to 174 from the N terminus of a wild-type FGF21 protein, is substituted with TGLEAV(SEQ ID NO: 54). In addition, the TGLEAN(SEQ ID NO: 55) refers to a mutation in which GPSQG(SEQ ID NO: 58), the amino acids at positions 170 to 174 from the N terminus of a wild-type FGF21 protein, is substituted with TGLEAN(SEQ ID NO: 55). Further, the G170N refers to a mutation in which G, the amino acid at position 170 from the N terminus of a wild-type FGF21 protein, is substituted with N. In addition, the G174N refers to a mutation in which G, the amino acid at position 174 from the N terminus of a wild-type FGF21 protein, is substituted with N.


Furthermore, the FGF21 mutant proteins may have a conformation, in which 1 to 10 amino acids at the N-terminus or C-terminus is (are) deleted as compared to the wild-type FGF21 protein. More preferably, the FGF21 mutant proteins may include an amino acid sequence represented by any one of SEQ ID NOs: 6 to 23. Still more preferably, the FGF21 mutant proteins may include an amino acid sequence represented by any one of SEQ ID NOs: 6 to 23 and further have a conformation, in which 1 to 10 amino acids at the N-terminus or C-terminus is (are) deleted as compared to the wild-type FGF21 protein.


In the dual function protein, an amino acid residue N of FGF21 mutant protein introduced by a mutation may be glycosylated.


Biologically Active Protein


The biologically active protein may be one selected from the group consisting of insulin, C-peptide, leptin, glucagon, gastrin, gastric inhibitory polypeptide (GIP), amylin, calcitonin, cholecystokinin, peptide YY, neuropeptide Y, bone morphogenetic protein-6 (BMP-6), bone morphogenetic protein-9 (BMP-9), oxyntomodulin, oxytocin, glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), irisin, fibronectin type III domain-containing protein 5 (FNDC5), apelin, adiponectin, C1q and tumor necrosis factor related protein (CTRP family), resistin, visfatin, omentin, retinol binding protein-4 (RBP-4), glicentin, angiopoietin, interleukin-22 (IL-22), exendin-4 and growth hormone. Preferably, the biologically active protein may be one selected from GLP-1, a mutant thereof and exendin-4.


The GLP-1 protein is an incretin hormone consisting of 31 amino acids, which is to secreted by L cells in the intestinal tract stimulated by food, etc. For example, the GLP-1 protein may be represented by the amino acid sequence of SEQ ID NO: 29.


A mutant of GLP-1 may be represented, for example, by the amino acid sequence of any one of SEQ ID NOs: 30 to 33.


Fc Region of Immunoglobulin


As used herein, the term “Fe region.” “Fc fragment,” or “Fc” refers to a protein, which includes a heavy chain constant region 1 (CH1), a heavy chain constant region 2 (CH2) and a heavy chain constant region 3 (CH3) of an immunoglobulin, but does not include variable regions of the heavy and light chains and a light chain constant region 1 (CLI) of an immunoglobulin. Additionally, as used herein, the term “Fe region mutant” refers to one prepared by substituting part of amino acid(s) of an Fe region or by combining Fc regions of different types.


The Fc region of immunoglobulin may be an entire Fc region constituting an antibody, a fragment thereof, or an Fc region mutant. Additionally, the Fc region includes a molecule in the form of a monomer or multimer, and may further include a hinge region of the heavy chain constant region. The Fc region mutant may be modified to prevent cleavage at the hinge region. Furthermore, the hinge sequence of the Fc may have a substitution in some amino acid sequences to reduce antibody-dependent cell-mediated cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC). In addition, part of the amino acid sequence of the Fc hinge sequence may be substituted to inhibit the rearrangement of the Fab region, lysine residue at the C-terminus of the Fe may be removed.


Preferably, the Fc region of immunoglobulin may be any one of IgG1, IgG2, IgG3, IgG4 and IgD Fc regions; or a hybrid Fe, which is a combination thereof. Further, the hybrid Fc may include an IgG4 region and an IgD region. Further, the hybrid Fc region may include part of the hinge sequence and CH2 of an IgD Fe, and CH2 and CH3 sequences of IgG4 Fc.


In addition, the Fc fragment of the present invention may be in the form of wild-type glycosylated chain, more glycosylated chain than the wild-type, less glycosylated chain than the wild-type, or deglycosylated chain. The increase, decrease, or removal of glycosylated chain may be performed by a conventional method known in the art, such as a chemical method, an enzymatic method, and a genetic engineering method using microorganisms.


Preferably, the immunoglobulin Fc region may be represented by an amino acid sequence selected from SEQ ID NOs: 24 to 28.


Dual Function Protein


The dual function protein may include a biologically active protein, an Fc region of an immunoglobulin and an FGF21 mutant protein, linked in this order from the N-terminus to the C-terminus. Further, the dual function protein may include an FGF21 mutant protein, an Fc region of an immunoglobulin and a biologically active protein, linked in this order from the N-terminus to the C-terminus. Preferably, the dual function protein may include a GLP-1 mutant protein, an Fc region of an immunoglobulin and an FGF21 mutant protein, linked in this order from the N-terminus to the C-terminus. Further, the dual function protein may include an FGF21 mutant protein, an Fc region of an immunoglobulin and a GLP-1 mutant protein, linked in this order from the N-terminus to the C-terminus.


Linker


Additionally; the dual function protein may further include a linker.


The dual function protein may be in the form, in which the FGF21 mutant protein is directly connected to the N-terminus or C-terminus of the immunoglobulin Fc region, or the FGF21 mutant protein is connected to the immunoglobulin Fe region via a linker.


In such case, the linker may be connected to the N-terminus, C-terminus, or a free radical of the Fc fragment, and also, may be connected to the N-terminus, C-terminus, it) or a free radical of the FGF21 mutant protein. When the linker is a peptide linker, the connection may occur in any region. For example, the linker may be connected to the C-terminus of the immunoglobulin Fc region and the N-terminus of the FGF21 mutant protein to form a fusion protein of the immunoglobulin Fc region and the FGF21 mutant protein. Furthermore, the dual function protein of the present invention may be in the form, in which a biologically active protein is linked to the N-terminus of the Fc region of immunoglobulin of the fusion protein.


When the linker and Fe are separately expressed and then connected, the linker may be a crosslinking agent known in the art. Examples of the crosslinking agent may include 1,1-bis(diazoacetyl)-2-phenylethane, glutaraldehyde, imidoesters including N-hydroxysuccinimide ester such as 4-azidosalicylic acid and disuccinimidyl esters such as 3,3′-dithiobis(succinimidylpropionate), and bifunctional maleimides such as bis-N-maleimido-1,8-octane, but are not limited thereto.


Further, the linker may be a peptide. Preferably, the linker may be a peptide consisting of 10 to 30 amino acid residues.


Furthermore, alanine may additionally be attached to the end of linker. Preferably, the linker may be a peptide having an amino acid sequence represented by any one of SEQ ID NOs: 2 to 5.


The dual function protein may be in a form in which a dimer or multimer of FGF21 mutant proteins, in which one or more FGF21 mutant proteins linked together, is connected to an immunoglobulin Fe region. Additionally, the dual function protein may be in a form of a dimer or multimer in which two or more immunoglobulin Fc regions are linked, wherein the immunoglobulin Fe regions have the FGF21 mutant protein connected thereto.


Mammalian Host Cell


The mammalian host cell may be any animal cell capable of expressing a recombinant dual function protein, preferably an animal cell which allows easy isolation of a targeted transformed cell. Specifically, the mammalian host cells may be immortal hybridoma cells, NS/0 myeloma cells, 293 cells, Chinese hamster ovary cells (CHO cells), HeLa cells, CAP cells (human amniotic fluid-derived cells), or COS cells.


Dextran Sulfate


As a result of applying the protease inhibitor to the cell culture of a dual function protein of the present invention, the effect of preventing the clipping phenomenon of the dual function protein by the protease derived from the host cell was insufficient.


The dextran sulfate may have a weight average molecular weight of 20 to 5,000 kDa. Specifically, the dextran sulfate may have a weight average molecular weight of 200 to 5,000 kDa.


In addition, the culture medium may contain the dextran sulfate at a concentration of 0.01 to 10 g/L. Specifically, the culture medium may contain the dextran sulfate at a concentration of 0.1 to 10 g/L, or 0.1 to 1 g/L.


Culture


The culturing may comprise a step for primary-culturing the mammalian host cell at 34 to 37° C. in a culture medium supplemented with dextran sulfate; and a step for secondary-culturing the primary-cultured medium at 28 to 33° C. Specifically, the primary-culturing may be conducted for 24 to 144 hours. Also, the secondary-culturing may be conducted at 31 to 33° C.


The dual function protein is a polypeptide in which GLP-1 and FGF21 variants, biologically active proteins, are fused to the Fc region of an immunoglobulin, and is expressed in an intact form when produced by animal cell culture, and shows activity as a composition for preventing or treating hepatitis, hepatic fibrosis, and hepatic cirrhosis.


MODE FOR THE INVENTION

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the examples. However, these examples according to the present invention can be modified in many different forms and the scope of the present invention should not be construed as limited to the examples set forth herein.


EXAMPLES
Preparation Example 1. Preparation of Host Cells for Expression of Dual Function Proteins

1-1: Preparation of Expression Vectors for Expression of Dual Function Proteins


The position, sequence information, target and expected effect of each mutation introduced into the FGF21 protein are listed in Table 1 below (in Table 1, N refers to glycosylated asparagine (N)). Further, FGF21 mutant proteins including the mutations described in Table 1 are listed in Table 2 below.














TABLE 1





Se-
Posi-
Original
Mutated

Expected


quence
tion
sequence
sequence
Target
effect







EIRP
98-
LLLE
EIRP
Substi-
Improve-


(SEQ
101
(SEQ ID
(SEQ ID
tution 
ment of


ID

NO: 57)
NO: 53)
with 
stability 


NO:



FGF19
and


53)



sequence
pharmaco-







kinetics





TGLEAV
170-
GPSQG
TGLEAV
Substi-
Improve-


(SEQ
174
(SEQ ID
(SEQ ID
tution 
ment of


ID

NO: 58)
NO: 54)
with 
pharmaco-


NO:



FGF19
kinetics


54)



sequence






TGLEAN
170-
GPSQG
TGLEAN
Substi
Improve-


(SEQ
174
(SEQ ID
(SEQ ID
tution 
ment of


ID

NO: 58)
NO: 55)
with 
pharmaco-


NO:



FGF19 
kinetics


55)



sequence,







and







addition 







of N-







glyco-







sylation






G170N
170
G
N
Point 
Improve-






mutation, 
ment of






and ad-
pharmaco-






dition of
kinetics






N-glyco-







sylation






G174N
174
G
N
Point 
Improve-






mutation, 
ment of






and ad-
pharmaco-






dition of
kinetics






N-glyco-







sylation






A180E
180
A
E
Point 
Improve-






mutation
ment of







pharmaco-







kinetics

















TABLE 2






Sequence of FGF21


SEQ ID NO
mutant protein







 6
FGF21 (EIRP)





 7
FGF21 (TGLEAV)





 8
FGF21 (TGLEAN)





 9
FGF21 (G170N)





10
FGF21 (G174N)





11
FGF21 (EIRP, TGLEAV)





12
FGF21 (EIRP, TGLEAN)





13
FGF21 (EIRP, G170N)





14
FGF21 (EIRP, G174N)





15
FGF21 (EIRP, A180E)





16
FGF21 (TGLEAV, A180E)





17
FGF21 (TGLEAN, A180E)





18
FGF21 (G170N, A180E)





19
FGF21 (G174N, A180E)





20
FGF21 (EIRP, TGLEAV, A180E)





21
FGF21 (EIRP, TGLEAN, A180E)





22
FGF21 (EIRP, G170N, A180E)





23
FGF21 (EIRP, G174N, A180E)









The GLP-1 mutant protein sequences are shown in Table 3 below, and the Fc fusion GLP-1 mutant protein sequences are shown in Table 4.










TABLE 3






Sequence of GLP-1


SEQ ID NO
mutant protein







30
GLP-1 (A2G)





31
GLP-1 (GE)





32
GLP-1 (GG)





33
GLP-1 (GEG)

















TABLE 4






Fc fusion GLP-1 mutant


SEQ ID NO
protein







34
DFD52: GLP1(A2G)-HyFc5





35
DFD53: GLP1(A2G)-HyFc40





36
DFD54: GLP1(GE)-HyFc5





37
DFD55: GLP1(GE)-HyFc40





38
DFD56: GLP1(GG)-HyFc5





39
DFD57: GLP1(GG)-HyFc40





40
DFD58: GLP1(GEG)-HyFc5





41
DFD59: GLP1(GEG)-HyFc40









In Table 4, HyFc5 represents SEQ ID NO: 27 and HyFc40 represents SEQ ID NO: 28.


Further, the sequences of the dual function proteins including the GLP-1 mutant proteins and FGF21 mutant proteins are listed in Table 5 below. Each dual function protein contains a GLP-1 mutant protein, an Fc region of an immunoglobulin, a linker and an FGF21 mutant protein connected in this order from the N-terminus to C-terminus.














TABLE 5







Se-







quence


Changes




of


in


SEQ

GLP-1

Linker
FGF21


ID
Material
mutant
Fusion
se-
se-


NO
code
protein
carrier
quence
quence







43
DFD23
GLP-1
hyFc40
GS3
FGF21




(A2G)
(SEQ ID
(SEQ ID 
(EIRP, 





 NO: 28)
NO: 4)
TGLEAV)





44
DFD24
GLP-1
hyFc5
GS3
FGF21




(GE)
(SEQ ID 
(SEQ ID 
(EIRP, 





NO: 27)
NO: 4)
TGLEAV)





45
DFD25
GLP-1
hyFc40
GS3
FGF21




(GE)
(SEQ ID 
(SEQ ID 
(EIRP, 





NO: 28)
NO: 4)
TGLEAV)





46
DFD26
GLP-1
hyFc5
GS3
FGF21




(GG)
(SEQ ID 
(SEQ ID 
(EIRP, 





NO: 27)
NO: 4)
TGLEAV)





47
DFD27
GLP-1
hyFc40
GS3
FGF21




(GG)
(SEQ ID 
(SEQ ID 
(EIRP, 





NO: 28)
NO: 4)
TGLEAV)





48
DFD28
GLP-1
hyFc5
GS3
FGF21




(GEG)
(SEQ ID 
(SEQ ID 
(EIRP, 





NO: 27)
NO: 4)
TGLEAV)





49
DFD29
GLP-1
hyFc40
GS3
FGF21




(GEG)
(SEQ ID 
(SEQ ID 
(EIRP, 





NO: 28)
NO: 4)
TGLEAV)





50
DFD69
GLP-1
hyFc40
GS3
FGF21




(GEG)
(SEQ ID 
(SEQ ID 
(EIRP,





NO: 28)
NO: 4)
TGLEAV, 







A180E)





51
DFD112
GLP-1
hyFc40
GS3
FGF21




(GEG)
(SEQ ID 
(SEQ ID 
(EIRP,





NO: 28)
NO: 4)
TGLEAN, 







A180E)





52
DFD114
GLP-1
hyFc40
GS3
FGF21




(GEG)
(SEQ ID 
(SEQ ID 
(EIRP,





NO: 28)
NO: 4)
G170N, 







A180E)









Specifically, the nucleotide sequences encoding each of the dual function proteins were synthesized after consulting with Bioneer Corporation (Korea) based on the amino acid sequence of each protein. NheI and NotI restriction enzyme sequences were added to the 5′ terminus and terminus of the nucleotide sequences encoding each of the dual function proteins and an initiation codon for protein translation and a leader sequence (SEQ ID NO: 56, MDAMLRGLCCVLLLCGAVFVSPSHA) enabling secretion of the expressed protein to the outside of a cell were inserted next to the restriction enzyme sequence at the 5′ terminus. A termination codon was inserted to next to the nucleotide sequence, which encodes each of the FGF21 mutant proteins. The nucleotide sequence encoding each of the dual function proteins was cloned into a pTrans-empty expression vector by using the two restriction enzymes NheI and NotI. The pTrans-empty expression vector, which has a CMV promoter, a pUC-derived replication origin, an SV40-derived replication origin and an ampicillin-resistance gene, was purchased from CEVEC Pharmaceuticals (Germany).


1-2: Construction of Plasmid DNA for Expression of Dual Function Proteins



E. coli was transformed with each of the expression vectors constructed in Preparation Example 1-1 to obtain a large quantity of plasmid DNA to be used for expression. E. coli cells, with cell walls weakened through heat shock, were transformed with each expression vector, and the transformants were plated out on an LB plate to obtain colonies. The colonies thus obtained were inoculated into LB media, cultured at 37° C. for 16 hours, and each E. coli culture containing each expression vector was obtained in a volume of 100 mL. The E. coli thereafter obtained was centrifuged to remove the culture medium, and then P1, P2, P3 solutions (QIAGEN, Cat No.:12963) were added to break the cell walls, thereby obtaining a DNA suspension in which proteins and DNA were separated. Plasmid DNA was purified from the DNA suspension thus Obtained by using a Qiagen DNA purification column. The eluted plasmid DNA was identified by agarose gel electrophoresis, and the concentrations and purities were measured using a nanodrop device (Thermo Scientific, Nanodrop Lite). The DNA thus obtained was used for expression.


1-3: Production of Transformed Host Cells for Expression of Dual Function Proteins


CHO DG44 cells (Chinese hamster ovary cells) were transformed with each plasmid DNA isolated in Preparation Example 1-2 using FreeStyleMAX (Invitrogen, Cat. No. 16447-100). The transformed Chinese hamster ovary cells were inoculated into a medium (CD OptiCHO, Gibco, Cat. No. 12681-011), and cultured in an incubator under the condition of 8% CO2 and 37° C., to select and culture surviving cells with passages repeatedly. The selected cells were finally selected as a single clone by limiting dilution in a 96-well plate.


Experimental Example 1. Suspension Culture for Expression of Dual Function Proteins, and Decomposition Phenomenon

The CHO cell line transformed with the material code DFD112 (SEQ ID NO: 51) of Preparation Example 1-3 was suspension-cultured in CD OptiCHO medium supplemented with 8 mM GlutaMAX (working volume 30 ml/125 ml flask, 37° C., 8% CO2, 120 rpm). Thereafter, the culture supernatants were stored at three different storage temperatures (37° C., 4° C., or −20° C.) for 3 days, and then the degrees of proteolysis phenomenon were evaluated by SDS-PAGE (4-12% Bis-Tris, non-reducing condition) analysis of the culture supernatant. The results of SDS-PAGE analysis are shown in FIGS. 1 and 2.


As shown in FIG. 1, it was found that proteins (85 to 110 kDa) smaller than target proteins were expressed along with the target proteins which were unclipped (intact) during cell culture for producing dual function proteins.


As shown in FIG. 2, the culture supernatants stored at 4° C. and −20° C. had less small-sized proteins in which the dual function proteins were clipped as compared to the culture supernatant stored at 37° C. Accordingly, it was found that the decomposition phenomenon of the dual function protein was caused by the proteases secreted from the host cell present in the culture supernatant.


Experimental Example 2. Detection of Protease Inhibitors Involved in Dual Function Protein Decomposition

In order to examine the category of the proteases involved in the decomposition of the dual function proteins identified in Experimental Example 1, the culture supernatants of Experimental Example 1 was added with various protease inhibitors, and treated for 3 days at 37° C., which were then subjected to SDS-PAGE analysis. The protease inhibitors used herein are shown in Table 6, and SDS-PAGE analysis results are shown in FIG. 3.












TABLE 6








Treatment



Protease inhibitors
concentration









Culture supernatant (control)
N/A











4-(2-Aminoethyl)benzenesulfonyl
1
mM



fluoride (AEBSF)



Antipain
0.1
mM



Bestatin
0.04
mM



E-64
0.01
mM



EDTA disodium salt
1
mM



N-Ethylmaleimide
1
mM



Leupeptin
0.1
mM



Pepstatin
1.46
mM



Phosphoramidon
0.01
mM



Benzamidine-HCl
4
mM



ZnCl2
10
mM



Aprotinin
0.0008
mM










As shown in FIG. 3, it was found that the decomposition phenomenon of the dual function protein was reduced in the culture supernatants treated with proteases inhibitors related to serine protease such as AEBSF, Antipain, Leupeptin, Benzamidine-HCl and Aprotin. Accordingly, it was found that the decomposition phenomenon of the dual function protein was caused by the proteases derived from the host cell.


Example 1. Dextran Sulfate Treatment

In order to inhibit the clipping phenomenon occurring during cell culture of the dual function proteins, the transformed CHO cell line of Preparation Example 1-3 was suspension-cultured in CD Dynamis medium (Gibco, cat. No. A2661501) supplemented with 6 mM glutamine for 7 days (working volume 30 mL/125 mL flask, 37° C., 8% CO2, 120 rpm). As for the suspension culture, dextran sulfate (weight average molecular weight: 1.6 kDa or 500 kDa) was added to the culture medium at a concentration of 200 mg/L, and the culture was conducted at 32° C. by a low temperature-conversion and fed-batch culture method. Thereafter, the culture supernatant was analyzed by SDS-PAGE (4-12% Bis-Tris, non-reducing condition), and the result of the SDS-PAGE analysis and a schematic diagram thereof are shown in FIG. 4. In FIG. 4, w/o and Lane 1 are controls, 500 kDa and Lane 2 are the culture supernatants treated with 500 kDa dextran sulfate, and 1.6 kDa and Lane 3 are the culture supernatants treated with 1.6 kDa dextran sulfate.


As shown in FIG. 4, it was found that the clipping phenomenon of the dual function protein was effectively inhibited when dextran sulfate having a weight average molecular weight of 500 kDa was added to the culture medium.


Example 2. Effect of Dextran Sulfate According to Molecular Weight

The effective concentration range of dextran sulfate to be added, whose protective effect against the clipping phenomenon of the dual function protein during cell culture was identified in Example 1, was examined.


Specifically, the culture was conducted under the same condition as Example 1 except for adjusting the weight average molecular weight (1.6 kDa, 8 kDa or 200 kDa) and the concentration (100 mg/L, 200 mg/L or 500 mg/L) of the added dextran sulfate. Thereafter, the culture supernatant was analyzed by SDS-PAGE (4-12% Bis-Tris, non-reducing condition), and the result of SDS-PAGE analysis and its graph are shown in FIG. 5.


As shown in FIG. 5, the clipping phenomenon of the dual function protein was significantly reduced when the dextran sulfate having a molecular weight of 200 kDa or more was added to the culture medium at a concentration of 100 to 500 mg/L.


Example 3. Evaluation of Culture Conditions for Prevention of Dual Function Protein Decomposition

The culture conditions for maximizing the effect of preventing the clipping of dual function proteins by dextran sulfate identified in Examples 1 and 2 were examined.


Specifically, the culture was conducted under the same condition as Example 1 except that dextran sulfate of 500 kDa was added at a concentration of 0 mg/L to 1,000 mg/L. Herein, the experiment group in which the culture temperature was changed to 32° C. on Day 4 of culture was included (see Table 7 below). Then, the culture supernatant was analyzed by SDS-PAGE (4-12% Bis-Tris, non-reducing condition), and the result of SDS-PAGE analysis and its graph are shown in FIG. 6.











TABLE 7






Concentration of the



Lane
added Dextran sulfate
Culture condition







1
0
Culture at 32° C. for 3 days after




culture at 37° C. for 4 days


2

Culture at 37° C. for 7 days


3
200 mg/L
Culture at 32° C. for 3 days after




culture at 37° C. for 4 days


4

Culture at 37° C. for 7 days


5
600 mg/L
Culture at 32° C. for 3 days after




culture at 37° C. for 4 days


6

Culture at 37° C. for 7 days


7
1,000 mg/L  
Culture at 32° C. for 3 days after




culture at 37° C. for 4 days


8

Culture at 37° C. for 7 days









As shown in FIG. 6, it was found that the culture supernatants of the culture with the treatment of dextran sulfate having a weight average molecular weight of 500 kDa showed significantly reduced clipping phenomenon of the dual function protein as compared to the culture supernatants of the culture without the treatment of dextran sulfate. Also, it was found that when the temperature was changed during the culture, the clipping phenomenon of the dual function protein was more effectively inhibited.

Claims
  • 1. A method for producing a recombinant dual function protein from a mammalian host cell transformed with an expression vector containing cDNA encoding the recombinant dual function protein, the method comprising culturing the mammalian host cell in a culture medium supplemented with dextran sulfate, wherein the dual function protein comprises a fibroblast growth factor 21 (FGF21) mutant protein; a biologically active protein, or a biologically active mutant or biologically active fragment thereof; and an Fc region of an immunoglobulin, wherein the FGF21 mutant protein comprises one mutation selected from the group consisting of the following mutations (a), (b), (c), (d), and (e): (a) a substitution of amino acids at positions 98 to 101 from the N-terminus of a wild-type FGF21 protein with the amino acid sequence of EIRP (SEQ ID NO: 53);(b) a substitution of amino acids at positions 170 to 174 from the N-terminus of a wild-type FGF21 protein with the amino acid sequence of TGLEAV (SEQ ID NO: 54);(c) a substitution of amino acids at positions 170 to 174 from the N-terminus of a wild-type FGF21 protein with the amino acid sequence of TGLEAN (SEQ ID NO: 55);(d) a substitution of an amino acid at position 174 from the N-terminus of a wild-type FGF21 protein with the amino acid N; and(e) a combination of the (a) and (b), a combination of the (a) and (c), or a combination of the (a) and (d), andwherein the wild-type FGF21 protein in (a), (b), (c), and (d) comprises the amino acid sequence of SEQ ID NO: 1.
  • 2. The method according to claim 1, wherein the biologically active protein is one selected from the group consisting of insulin, C-peptide, leptin, glucagon, gastrin, gastric inhibitory polypeptide (GIP), amylin, calcitonin, cholecystokinin, peptide YY, neuropeptide Y, bone morphogenetic protein-6 (BMP-6), bone morphogenetic protein-9 (BMP-9), oxyntomodulin, oxytocin, glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), irisin, fibronectin type III domain-containing protein 5 (FNDC5), apelin, adiponectin, C1q and tumor necrosis factor related protein (CTRP family), resistin, visfatin, omentin, retinol binding protein-4 (RBP-4), glicentin, angiopoietin, interleukin-22 (IL-22), exendin-4 and growth hormone.
  • 3. The method according to claim 1, wherein the dual function protein comprises the biologically active protein, the Fc region of the immunoglobulin and the FGF21 mutant protein, connected in this order from the N-terminus to the C-terminus of the dual function protein.
  • 4. The method according to claim 1, wherein the dextran sulfate has a weight average molecular weight of 20 to 5,000 kDa.
  • 5. The method according to claim 1, wherein the culture medium contains the dextran sulfate at a concentration of 0.01 to 10 g/L.
  • 6. The method according to claim 1, wherein the culturing comprises: a step for primary-culturing the mammalian host cell at 34 to 37° C. in a culture medium supplemented with dextran sulfate; anda step for secondary-culturing the primary-cultured medium at 28 to 33° C.
  • 7. The method of claim 6, wherein the primary-culturing is conducted for 24 to 144 hours.
  • 8. The method of claim 6, wherein the secondary-culturing is conducted at 31 to 33° C.
Priority Claims (1)
Number Date Country Kind
10-2017-0051758 Apr 2017 KR national
PCT Information
Filing Document Filing Date Country Kind
PCT/KR2018/004599 4/20/2018 WO
Publishing Document Publishing Date Country Kind
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US Referenced Citations (21)
Number Name Date Kind
5851800 Adamson et al. Dec 1998 A
9023791 Boettcher et al. May 2015 B2
9434778 Morin et al. Sep 2016 B2
9441030 Song et al. Sep 2016 B2
9926351 Schellenberger et al. Mar 2018 B2
20100112641 Song May 2010 A1
20110034373 Coskun et al. Feb 2011 A1
20110195895 Walker et al. Aug 2011 A1
20120035099 Garibay et al. Feb 2012 A1
20120172298 Andersen et al. Jul 2012 A1
20120238496 Fan et al. Sep 2012 A1
20130129724 Boettcher et al. May 2013 A1
20130190232 Tagmose et al. Jul 2013 A1
20140073563 Boscheinen et al. Mar 2014 A1
20140213512 Ellison et al. Jul 2014 A1
20140243503 Belouski et al. Aug 2014 A1
20140323396 Belouski Oct 2014 A1
20180298078 Park et al. Oct 2018 A1
20180305428 Kim et al. Oct 2018 A1
20190314452 Hong et al. Oct 2019 A1
20200024318 Kim et al. Jan 2020 A1
Foreign Referenced Citations (69)
Number Date Country
101993496 Mar 2011 CN
102558358 Jul 2012 CN
102625811 Aug 2012 CN
102655877 Sep 2012 CN
102802657 Nov 2012 CN
103124562 May 2013 CN
103415300 Nov 2013 CN
104736558 Jun 2015 CN
105288592 Feb 2016 CN
020843 Feb 2015 EA
0 306 968 Mar 1989 EP
0 345 660 Dec 1989 EP
2 548 570 Jan 2013 EP
2006-520186 Sep 2006 JP
2009-534424 Sep 2009 JP
2010-531134 Sep 2010 JP
2011-518175 Jun 2011 JP
2011-523561 Aug 2011 JP
2012-504965 Mar 2012 JP
2012-515747 Jul 2012 JP
2012-525847 Oct 2012 JP
2014-510707 May 2014 JP
2014-526441 Oct 2014 JP
2014-527986 Oct 2014 JP
2015-527974 Sep 2015 JP
2018-522147 Aug 2018 JP
2018-534929 Nov 2018 JP
2019-500013 Jan 2019 JP
2020-502053 Jan 2020 JP
2 741 345 Jan 2021 RU
9002175 Mar 1990 WO
2003011213 Feb 2003 WO
03059934 Jul 2003 WO
2004058800 Jul 2004 WO
2005000892 Jan 2005 WO
2005091944 Oct 2005 WO
2007124463 Nov 2007 WO
2008147143 Dec 2008 WO
2009020802 Feb 2009 WO
2009129379 Oct 2009 WO
2009149171 Dec 2009 WO
2010042747 Apr 2010 WO
2010065439 Jun 2010 WO
2010084169 Jul 2010 WO
2010091122 Aug 2010 WO
2010129503 Nov 2010 WO
2010129600 Nov 2010 WO
2010142665 Dec 2010 WO
2011020319 Feb 2011 WO
2011028229 Mar 2011 WO
2011089170 Jul 2011 WO
2011154349 Dec 2011 WO
2012010553 Jan 2012 WO
2012066075 May 2012 WO
2012093127 Jul 2012 WO
2012170438 Dec 2012 WO
2013033452 Mar 2013 WO
2013049234 Apr 2013 WO
2013131091 Sep 2013 WO
2013188181 Dec 2013 WO
2014037373 Mar 2014 WO
2014130659 Aug 2014 WO
2015038938 Mar 2015 WO
2017065559 Apr 2017 WO
2017074117 May 2017 WO
2017074123 May 2017 WO
2018088838 May 2018 WO
2018166461 Sep 2018 WO
2018194413 Oct 2018 WO
Non-Patent Literature Citations (22)
Entry
Bedoya-López et al. Effect of Temperature Downshift on the Transcriptomic Responses of Chinese Hamster Ovary Cells Using Recombinant Human Tissue Plasminogen Activator Production Culture. PLoS One 11(3): e0151529, pp. 1-26 (Mar. 18, 2016). (Year: 2016).
Alexei Kharitonenkov et al., “FGF-21 as a novel metabolic regulator”, The Journal of Clinical Investigation, Jun. 2005, pp. 1627-1635, vol. 115, No. 6.
Bernard Thorens et al., “Cloning and Functional Expression of the Human Islet GLP-1 Receptor,” Diabetes, Nov. 1993, pp. 1678-1682, vol. 42.
H. Kahal et al., “Glucagon-like peptide-1 analogue, liraglutide, improves liver fibrosis markers in obese women with polycystic ovary syndrome and nonalcoholic fatty liver disease”, Clinical Endocrinology, 2014, pp. 523-528, vol. 81.
Hecht et al., “Rationale-Based Engineering of a Potent Long-Acting FGF21 Analog for the Treatment of Type 2 Diabetes”, PLOS One, Nov. 2012, vol. 7, Issue 11, e49345, pp. 1-14 (total 14 pages).
Jie Huang et al., “Development of a Novel Long-Acting Antidiabetic FGF21 Mimetic by Targeted Conjugation to a Scaffold Antibody”, The Journal of Pharmacology and Experimental Therapeutics, Aug. 2013, pp. 270-280, vol. 346.
Justin D. Schumacher et al., “Regulation of Hepatic Stellate Cells and Fibrogenesis by Fibroblast Growth Factors”, BioMed Research International, Jan. 2016 (Posted on ResearchGate), 21 pages.
English Translation of Office Action dated Jan. 28, 2021 in Russian Application No. 2019117767.
International Search Report of PCT/KR2018/004599 dated Aug. 21, 2018 [PCT/ISA/210].
Written Opinion of PCT/KR2018/004599 dated Aug. 21, 2018 [PCT/ISA/237].
Michelle Orlando, “Modification of proteins and low molecular weight substances with hydroxyethyl starch (HES)”, 2003, Inauguraldissertation, Giesen (191 pages).
Richard Smith et al., “FGF21 Can Be Mimicked In Vitro and In Vivo by a Novel Anti-FGFR1c/β-Klotho Bispecific Protein”, PLOS One, 2013, vol. 8, Issue 4, e61432 (11 pages total).
Xiaoying Chen et al., “Fusion Protein Linkers: Property, Design and Functionality”, Adv Drug Deliv Rev., 2013, vol. 65, No. 10, pp. 1357-1369 (32 pages total).
Joel D.A. Tyndall et al., “Over One Hundred Peptide-Activated G Protein-Coupled Receptors Recognize Ligands with Turn Structure”, Chem. Rev., 2005, vol. 105, No. 3, pp. 793-826 (34 pages total).
Yumi Maeda et al., “Engineering of Functional Chimeric Protein G-Vargula Luciferase”, Analytical Biochemistry, 1997, vol. 249, No. 2, pp. 147-152 (6 pages total).
H-D. Jakubke et al., “I am amino acids, peptides, proteins: Per-M: Mir”, 1985 (5 pages total).
H.N. Hong et al., “YH25724, a novel long-acting GLP-1/FGF21 dual agonist lowers both non-alcoholic fatty liver disease activity score and fibrosis stage in a diet-induced obese mouse model of biopsy-confirmed non-alcoholic steatohepatitis”, Journal of Hepatology, vol. 66; pp. S16-S17; published 2017.
Wolfgang Glaesner et al., “Engineering and characterization of the long-acting glucagon-like peptide-1 analogue LY2189265, an Fc fusion protein”, Diabetes/Metabolism Research and Reviews, V. 26, N. 4, p. 287-296; published Apr. 30, 2010.
Tokuriki et al., “Stability effects of mutations and protein evolvability”, Current Opinion in Structural Biology, v.19, n.5, p. 596-604; published 2009.
Shen et al., “Single Variable Domain-IgG Fusion: A Novel Recombinant Approach to Fc Domain-Containing Bispecific Antibodies”, Journal of Biological Chemistry, V. 281, N. 16, p. 10706-10714; published Apr. 21, 2006.
N.E. Kuzmina et al., “Quantitative Determination of the Mean Molecular Mass of Dextrans by Means of Diffusion-Ordered NMR Spectroscopy”, Journal of Analytical Chemistry, vol. 69, No. 10, pp. 1047-1053; published 2014.
Neidigh et al., “Exendin-4 and Glucagon-like-peptide-1: NMR Structural Comparisons in the Solution and Micelle-Associated States”, Biochemistry, vol. 40, No. 44, pp. 13188-13200; published Oct. 13, 2001.
Related Publications (1)
Number Date Country
20210188936 A1 Jun 2021 US