Establishment of a human somatic hybrid cell line for recombinant protein production.
Cell fusion techniques were used to derive mammalian host cell lines suitable for large-scale production of therapeutic proteins. Although the 293S cell line, of human embryonic kidney origin, is an excellent host cell for mammalian gene expression, these cells have a tendency to form large and tight aggregates in suspension cultures and bioreactors. To solve the problem of aggregation, 293S cells were fused to a human suspension cell line, 2B8 (a Burkitt's lymphoma derivative), using polyethylene glycol (PEG). The PEG-treated 293S and 2B8 cells were selected in a medium supplemented with hypoxanthine-aminopterin-thymidine and G418 (1 mg/ml) to eliminate nonfused cells. These hybrid clones, designated as HKB (hybrid of kidney and B cells), are negative for endogenous immunoglobulin expression. Most clones are readily adaptable to serum-free suspension culture under shaking conditions without forming large and tight aggregates. One clone, HKB11, was shown to support high-level expression of cytokines [interleukin (IL)-2 and IL-4], ICAM-1 and rFVIII in a side-by-side comparison with 293 and Chinese hamster ovary cells. The above-described characteristics of HKB cells indicate that HKB11 is a favorable cell host for the production of human therapeutic proteins.
Cho
M S
MS
Molecular and Cell Biology, Process Sciences, Biotechnology, Bayer Corporation, Berkeley, Calif 94701-1986, USA. myung-sam.cho.b@bayer.com
Yee
H
H
Chan
S
S
D002051:Burkitt Lymphoma / Q000473:pathology; D002449:Cell Aggregation; D018929:Cell Culture Techniques / Q000379:methods; D002459:Cell Fusion / Q000379:methods; D016207:Cytokines / Q000096:biosynthesis; D015870:Gene Expression; D006801:Humans; D006822:Hybrid Cells; D007136:Immunoglobulins / Q000032:analysis; D007668:Kidney / Q000166:cytology; D011994:Recombinant Proteins / Q000096:biosynthesis*
D016207:Cytokines; D007136:Immunoglobulins; D011994:Recombinant Proteins