Cell culture media and methods

Abstract

Compositions and methods are described for preparing media, feeds, and supplements. Such methods and medias may display increased stability of labile components and may use, for example, microsuspension and/or encapsulation technologies, chelation, and optionally, coating and/or mixing the labile compounds with anti-oxidants. The compositions may withstand thermal and/or irradiation treatment and have reduced virus number. These techniques may result in product with extended shelf-life, extended release of their internal components into culture, or in product that can be added aseptically into a bioreactor using minimal volumes. The compositions and methods may optimize the bioproduction workflow and increase efficiency.

What is claimed is: 
     
         1 . A process for extending the release of a component in a cell culture medium, feed or supplement, the process comprising:
 (i) adding a minimal volume of an aqueous solution to a dry powder cell culture medium, feed or supplement comprising the component for extended release, to make a paste;   (ii) mixing the paste vigorously to prepare a microsuspension;   (iii) optionally, adding an effective amount of an anti-oxidant to the microsuspension of (ii) to form a mixture;   (iv) encapsulating the microsuspension of (ii), or the mixture of (iii), into a capsular material to form a bead; and   (v) drying the bead.   
     
     
         2 . The process of  claim 1 , wherein the component is selected from the group consisting of glucose, a vitamin, an amino acid or its derivative, a peptides, a macromolecule, a polyamine, a hormone, a growth factor and a labile substance. 
     
     
         3 . The process of  claim 2 , wherein the microsuspension of step (iv) concentrates the contents within the bead. 
     
     
         4 . The process of  claim 1 , wherein the capsular material is selected from the group consisting of alginate, poly-L-lactic acid, chitosan, agarose, gelatin, hyaluronic acid, chondroitin sulfate, dextran, dextran sulfate, heparin, heparin sulfate, heparan sulfate, gellan gum, xanthan gum, guar gum, water soluble cellulose derivatives and carrageenan. 
     
     
         5 . The process of  claim 1 , wherein the bead is coated with a coating solution that further extends the release of the component from the bead. 
     
     
         6 . The process of  claim 5 , wherein the coating solution is selected form the group consisting of poly-glycolic acid, PLGA (poly-lactic-co-glycolic acid), collagen, polyhydroxyalkanoates (PHA), poly-ε-caprolactone, poly-ortho esters, poly-anhydrides, poly-phosphazenes, poly-amino acids, polydimethylsiloxane, polyurethranes, poly-tetrafluoroethylene, polyethylene, polysulphone, poly-methyl methacrylate, poly-2-hydroxyethylmethacrylate, polyamides, polypropylene, poly-vinyl chloride, polystyrene, poly-vinyl pyrrolidone, poly-L-lysine and polyornithine. 
     
     
         7 . The process of  claim 6 , wherein greater than 50% of the extended release component in the microsuspension is present after 15 days in culture. 
     
     
         8 . The process of  claim 4 , wherein the capsular material encapsulates a dendrimer-component complex. 
     
     
         9 . The process of  claim 8 , wherein the dendrimer is a polyamidoamine dendrimer, a polypropylenimine dendrimer, or a polypropylamine (POPAM) dendrimer. 
     
     
         10 . The process of  claim 1 , wherein dry powder cell culture medium, feed or supplement is either fine-milled or AGT (advanced granulation technology cell culture medium). 
     
     
         11 . The process of  claim 1 , wherein the composition further comprises chelated reactive species. 
     
     
         12 . The process of  claim 11 , wherein the reactive species is a cation, a metal ion, or a trace element. 
     
     
         13 . The process of  claim 11 , wherein the chelating moieties are selected from the group consisting of EDTA, citrate, succinate, cyclodextrin, clatharates, dendrimers and amino acids. 
     
     
         14 . The process of  claim 1 , wherein the cell culture medium, feed or supplement is irradiated. 
     
     
         15 . The process of  claim 14 , wherein the cell culture medium, feed or supplement is free of PPV and MMV viruses. 
     
     
         16 . Use of the cell culture medium, feed or supplement comprising the extended release component of  claim 2 , to produce a liquid medium for culturing a cell.
 wherein the delayed-release of the component into the cell culture for over 6-24 hours, 24-48 hours, 48-72 hours, over 1 day, 2 days, 3-5 days, 5-10 days, 10-15 days, 15-20 days, 20-25 days, 25-30 days, 30-40 days, 40-50 days, over the duration of the culture.   
     
     
         17 . The use of the cell culture medium, feed or supplement of  claim 16 , wherein the medium, feed or supplement comprising the extended release component is stored at ambient temperatures. 
     
     
         18 . The use of the cell culture medium, feed or supplement of  claim 1  wherein the cell is a mammalian cell. 
     
     
         19 . The use of the cell culture medium, feed or supplement of  claim 18 , wherein the mammalian cell is selected from the group consisting of Chinese Hamster Ovary (CHO) cells, 293, BHK, Vero, PerC6, MDBK and MDCK cells. 
     
     
         20 . The use of the cell culture medium, feed or supplement of  claim 18 , wherein the mammalian cell is a CHO cell.