METHOD OF PRODUCING BIOLOGICALLY ACTIVE VITAMIN K DEPENDENT PROTEINS BY RECOMBINANT METHODS
The invention relates to commercially viable methods for producing biologically active vitamin R dependent proteins, particularly Factor IX. Factor IX is produced at a level of at least about 15 mg/L and is at least 25% biologically active. The method relies upon co-expression of one or more of paired basic amino acid converting enzyme (PACE), vitamin K dependent epoxide reductase (VKOR) and vitamin K dependent γ-glutamyl carboxylase (VKGC) at a preferred ratio so that the vitamin K dependent protein is efficiently produced and processed by a recombinant cell.
1 .- 35 . (canceled)
36 . A method of producing a mammalian cell that produces a high level of recombinant biologically active vitamin K dependent protein comprising transfecting a mammalian cell with:
(i) a gene encoding a vitamin K dependent protein,
(ii) a gene encoding vitamin K dependent epoxide reductase (VKOR), and
(iii) a gene encoding vitamin K dependent γ-glutamyl carboxylase (VKGC); wherein the gene encoding the vitamin K dependent protein is operably linked to a Chinese hamster elongation factor 1-α (CHEF1) promoter, and
wherein the cell produces at least about 15 mg/L of a recombinant vitamin K dependent protein, and wherein at least 60% of the recombinant vitamin K dependent protein is biologically active.
37 . The method of claim 36 , wherein the vitamin K dependent protein is selected from the group consisting of Factor II, Factor VII, Factor IX, Factor X, Protein C and Protein S.
38 . The method of claim 36 , wherein the mammalian cell further comprises a gene encoding paired basic amino acid converting enzyme (PACE) operably liked to a promoter.
39 . The method of claim 36 , wherein at least about 75% of the glutamic acid residues within the gla-domain of the recombinant biologically active vitamin K dependent protein are gamma carboxylated.
40 . The method of claim 36 , wherein the mammalian cell is a CHO cell or HEK 293 cell.
41 . The method of claim 36 , wherein at least 70% or at least 80% of the recombinant vitamin K dependent protein is biologically active.
42 . The method of claim 36 , wherein (ii) and/or (iii) are operably linked to the Chinese hamster elongation factor 1-α (CHEF1) promoter.
43 . The method of claim 36 , wherein (ii) and/or (iii) are operably linked to a promoter that is not the Chinese hamster elongation factor 1-α (CHEF1) promoter.
44 . The method of claim 36 , wherein (ii) and (iii) are operably linked to different promoters or the same promoter.
45 . A mammalian cell that produces a high level of recombinant biologically active vitamin K dependent protein, wherein the cell comprises:
(i) a gene encoding a vitamin K dependent protein,
(ii) a gene encoding vitamin K dependent epoxide reductase (VKOR), and
(iii) a gene encoding vitamin K dependent γ-glutamyl carboxylase (VKGC);
wherein the gene encoding the vitamin K dependent protein is operably linked to a Chinese hamster elongation factor 1-α (CHEF1) promoter, and
wherein the cell produces at least about 15 mg/L of a recombinant vitamin K dependent protein, and wherein at least 60% of the recombinant vitamin K dependent protein is biologically active.
46 . The cell of claim 45 , wherein the vitamin K dependent protein is selected from the group consisting of Factor II, Factor VII, Factor IX, Factor X, Protein C and Protein S.
47 . The cell of claim 45 , wherein the cell further comprises a gene encoding paired basic amino acid converting enzyme (PACE) operably liked to a promoter.
48 . The cell of claim 45 , wherein at least about 75% of the glutamic acid residues within the gla-domain of the recombinant biologically active vitamin K dependent protein are gamma carboxylated.
49 . The cell of claim 45 , wherein the cell is a CHO cell or a HEK 293 cell.
50 . The cell of claim 45 , wherein at least 70% or at least 80% of the recombinant vitamin K dependent protein is biologically active.
51 . The cell of claim 45 , wherein (ii) and/or (iii) are operably linked to the Chinese hamster elongation factor 1-α (CHEF1) promoter.
52 . The cell of claim 45 , wherein (ii) and/or (iii) are operably linked to a promoter that is not the Chinese hamster elongation factor 1-α (CHEF1) promoter.
53 . The cell of claim 45 , wherein (ii) and (iii) are operably linked to different promoters or to the same promoter.
54 . A method of producing a high level of recombinant biologically active vitamin K dependent protein comprising:
(a) transfecting mammalian cells with (i) a gene encoding the vitamin K dependent protein operably linked to a Chinese hamster elongation factor 1-α (CHEF1) promoter, and, (ii) a gene encoding vitamin K dependent epoxide reductase (VKOR) operably linked to a CHEF1promoter; and
(b) harvesting recombinant vitamin K dependent protein produced by the mammalian cells; wherein the mammalian cells produce at least about 15 mg/L of the recombinant vitamin K dependent protein, and wherein at least 60% of the recombinant vitamin K dependent protein is biologically active.
55 . A method of producing a high level of recombinant biologically active vitamin K dependent protein comprising:
(a) transfecting mammalian cells with (i) a gene encoding the vitamin K dependent protein operably linked to a Chinese hamster elongation factor 1-α (CHEF1) promoter, and, (ii) a gene encoding vitamin K dependent y-glutamyl carboxylase (VKGC) operably linked to a CHEF1 promoter; and
(b) harvesting recombinant vitamin K dependent protein produced by the mammalian cells; wherein the mammalian cells produce at least about 15 mg/L of the recombinant vitamin K dependent protein, and wherein at least 60% of the recombinant vitamin K dependent protein is biologically active.