Identification of novel small molecule enhancers of protein production by cultured mammalian cells.
Small molecule additives to cell culture media (e.g., sodium butyrate) that are capable of enhancing the expression of recombinant proteins have significant utility in the production and manufacture of therapeutic polypeptides. To identify novel small molecule enhancers (SMEs) of recombinant protein expression in Chinese Hamster Ovary (CHO) cells, we screened two separate small molecule libraries for compounds capable of enhancing the expression of either a fluorescent reporter protein or a monoclonal antibody. Several compounds that increased recombinant protein expression were identified, and these compounds fell into three broad classes: (1) aromatic carboxylic acids, (2) hydroxamic acids, and (3) acetamides. We examined the impact of SME addition to CHO cell cultures expressing different classes of recombinant proteins including monoclonal antibodies (MAbs). For CHO cell pools or clones grown in production shake-flasks or bioreactors, recombinant protein titers up to 60% higher than control cultures were observed. Analysis of mRNA levels suggest that transcriptional activation plays a role in the expression enhancement seen for some SMEs, but other mechanisms may be involved for at least one compound. Finally, we tested many of the identified SMEs for their ability to increase MAb production by a hybridoma cell line. Hexanohydroxamic acid increased shake-flask MAb production by 40% relative to a control. Taken together, these data demonstrate the potential utility of the compounds in the production of therapeutically relevant proteins from diverse cell-based production systems.
Allen
Martin J
MJ
Department of Cell Science and Technology, Amgen, 1201 Amgen Court West, Seattle, Washington 98119, USA. allema@amgen.com <allema@amgen.com>
Boyce
James P
JP
Trentalange
Michael T
MT
Treiber
David L
DL
Rasmussen
Brian
B
Tillotson
Benjamin
B
Davis
Raymond
R
Reddy
Pranhitha
P
D000081:Acetamides / Q000494:pharmacology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis / Q000096:biosynthesis*; D019149:Bioreactors; D016466:CHO Cells; D002208:Caproates / Q000494:pharmacology; D018929:Cell Culture Techniques; D006224:Cricetinae; D003412:Cricetulus; D003470:Culture Media; D005260:Female; D005456:Fluorescent Dyes; D015870:Gene Expression / Q000187:drug effects; D024861:Genetic Enhancement / Q000379:methods; D006825:Hybridomas; D006841:Hydrocarbons, Aromatic / Q000494:pharmacology*; D006877:Hydroxamic Acids / Q000494:pharmacology*; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000096:biosynthesis*; D015533:Transcriptional Activation / Q000187:drug effects
D000081:Acetamides; D000911:Antibodies, Monoclonal; D002208:Caproates; D003470:Culture Media; D005456:Fluorescent Dyes; D006841:Hydrocarbons, Aromatic; D006877:Hydroxamic Acids; D011993:Recombinant Fusion Proteins