Role of environmental conditions on the expression levels, glycoform pattern and levels of sialyltransferase for hFSH produced by recombinant CHO cells

• DOI: 10.1007/bf00762396
• Publication Date: 2004-12-09T19:39:09Z
• Authors: W. Chotigeat; Y. Watanapokasin; S. Mahler; P. P. Gray
• Keywords: 0301 basic medicine; Glycosylation; Time Factors; CHO; Perfusion cultures; Gene Expression; CHO Cells; 03 medical and health sciences; Cricetinae; Culture Techniques; Animals; Humans; Promoter Regions, Genetic; Beta actin; Actins; Recombinant Proteins; Sialyltransferases; Oxygen; Butyrates; Kinetics; Sialic Acids; Butyric Acid; Follicle Stimulating Hormone; hFSH; Biotechnology

A recombinant CHO cell line in which the expression of human follicle stimulating hormone (hFSH) was under the control of the beta actin promoter was maintained in steady state perfusion cultures on a protein free medium. The level of expression of the hFSH was controlled by varying the steady state level of dissolved oxygen (10-90% of air saturation) and of sodium butyrate (0-1.5mM). Under these conditions, the specific productivity of hFSH (qFSH) varied from 0.7 to 4.8 ng hFSH/10(6) cells/h. As the specific productivity of hFSH increased, there was a shift in the FSH isoforms to the lower pI fractions, corresponding to increased sialic acid content. As the specific productivity of hFSH increased, shifting the isoform distribution towards the lower pI isoforms, that the sialyltransferase enzymic activity also increased.