Production and glycosylation of recombinant beta-interferon in suspension and cytopore microcarrier cultures of CHO cells.
Microcarriers are suitable for high-density cultures of cells requiring surface attachment and also offer the advantage of easy media removal for product recovery. We have used the macroporous microcarriers Cytopore 1 and 2 for the growth of CHO cells producing recombinant human beta-interferon (beta-IFN) in stirred batch cultures. Although these cells may grow in suspension, in the presence of Cytopore microcarriers they become entrapped in the inner bead matrix where they can be maintained at high densities. Cell growth rates were reduced in microcarrier cultures compared to suspension cultures. However, the beta-IFN yield was up to 3-fold greater as a result of an almost 5-fold higher specific productivity. Maximum productivity was found in cultures containing 1.0 mg/mL of Cytopore 1 or 0.5 mg/mL of Cytopore 2 with a cell/bead ratio of 1029 and 822, respectively. Beta-IFN molecules aggregated in the later stages of all cultures, causing a decrease in response by ELISA. However, the degree of aggregation was significantly less in the microcarrier cultures. The N-linked glycans from beta-IFN were isolated and analyzed by normal phase HPLC. There was no apparent difference in the profile of glycans obtained from each of the suspension and Cytopore culture systems. This suggests that Cytopore microcarriers may be useful in bioprocess development for enhanced recombinant glycoprotein production without affecting the glycosylation profile of the protein.
Spearman
Maureen
M
Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
Rodriguez
Jose
J
Huzel
Norm
N
Butler
Michael
M
D000818:Animals; D016466:CHO Cells; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D006224:Cricetinae; D003470:Culture Media / Q000494:pharmacology; D046508:Culture Techniques / Q000295:instrumentation / Q000379:methods; D006031:Glycosylation; D006801:Humans; D016899:Interferon-beta / Q000096:biosynthesis* / Q000187:drug effects; D008863:Microspheres; D016062:Porosity; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification; D013535:Suspensions; D013997:Time Factors
D003470:Culture Media; D011994:Recombinant Proteins; D013535:Suspensions; D016899:Interferon-beta