Process of production with controlled copper ions

Abstract

The present invention provides a method of cell culture comprising adding a cell-containing seed medium to an initial medium and starting to culture the cell in the initial medium, wherein the initial medium has an organism-derived culture medium additive added thereto and the amount of the C-terminal amidated species in the produced protein is controlled by the copper content of the initial medium at the start of cell culture.

1 - 28 . (canceled) 
     
     
         29 . A process for producing a protein using a method of cell culture comprising the steps of:
 (1) preliminarily measuring the copper content in an organism-derived culture medium additive to be added to a medium; and   (2) selecting the measured additive with a copper content of no more than 1 ppm and adding the same to an initial medium.   
     
     
         30 . The process according to  claim 29 , wherein the method of cell culture is batch culture, fed-batch culture, continuous culture, batch culture, or semi-batch culture. 
     
     
         31 . The process according to  claim 29 , wherein the method of cell culture is fed-batch culture. 
     
     
         32 . The process for producing a protein according to  claim 31 , wherein the method of cell culture is fed-batch culture, and the method of cell culture further comprises the step of:
 (3) selecting the measured additive with a copper content of no more than 3 ppm and adding the same to a fed-batch medium.   
     
     
         33 . A process for producing a pharmaceutical composition containing a desired protein, comprising the steps of:
 (1) producing the desired protein by the process according to  claim 29 ; and   (2) producing the pharmaceutical composition by mixing the desired protein produced in step (1) with a carrier and an additive that are pharmaceutically acceptable and formulating the same.   
     
     
         34 . The process according to  claim 29 , wherein the copper content of the initial medium at the start of cell culture is no more than 0.02 ppm. 
     
     
         35 . The process according to  claim 29 , wherein the copper content of the initial medium at the start of the cell culture is not more than 0.015 ppm. 
     
     
         36 . The process according to  claim 29 , wherein an organism-derived culture medium additive with a copper content of no more than 1 ppm has been added to the initial medium. 
     
     
         37 . The process according to  claim 34 , wherein the copper ions derived from the fed-batch medium are present at no more than 0.08 ppm in the medium at the end of culture. 
     
     
         38 . The process according to  claim 34 , wherein the copper ions in the medium at the end of culture are present at no more than 0.1 ppm. 
     
     
         39 . The process according to  claim 29 , wherein the organism-derived culture medium additive is an animal-derived or plant-derived culture medium additive. 
     
     
         40 . The process according to  claim 29 , wherein the organism-derived culture medium additive is a fish-derived culture medium additive. 
     
     
         41 . The process according to  claim 29 , wherein the organism-derived culture medium additive is a fish meat hydrolyzate. 
     
     
         42 . The process according to  claim 29 , wherein the organism-derived culture medium additive to be added to the culture medium has been preliminarily measured for the copper content. 
     
     
         43 . The process according to  claim 29 , wherein the method of cell culture comprises culturing an animal cell. 
     
     
         44 . The process according to  claim 43 , wherein the animal cell is a mammalian cell. 
     
     
         45 . The process according to  claim 44 , wherein the mammalian cell is a CHO cell. 
     
     
         46 . The process according to  claim 29 , wherein the method of cell culture comprises culturing a cell that has been transfected with a gene coding for a desired protein. 
     
     
         47 . The process according to  claim 46 , wherein the desired protein is an antibody. 
     
     
         48 . The process according to  claim 47 , wherein the antibody is tocilizumab. 
     
     
         49 . A method of suppressing the generation of C-terminal amidated species in a desired protein by using the culture method according to  claim 29 . 
     
     
         50 . The method according to  claim 49 , wherein the desired protein is an antibody. 
     
     
         51 . A method of suppressing the generation of C-terminal amidated species in a desired protein by using the process according to  claim 32 . 
     
     
         52 . The method according to  claim 51 , wherein the desired protein is an antibody. 
     
     
         53 . A method of suppressing the generation of C-terminal amidated species in a desired protein by using the process according to  claim 41 . 
     
     
         54 . The method according to  claim 53 , wherein the desired protein is an antibody.