I worked briefly with Dr. Cho ("Sam") when we were getting the "process sciences" group off the ground. Very good scientist.......
Biotechnol Prog. 2003 Jan-Feb;19(1):229-32.
Versatile expression system for rapid and stable production of recombinant proteins.
Cho MS, Yee H, Brown C, Mei B, Mirenda C, Chan S.
Molecular and Cell Biology, Process Sciences, Bayer Biotechnology, 800 Dwight Way, Berkeley, California 94701-1086, USA.
Previously we reported the development of a novel expression system with Tat/TAR-oriP vectors and HKB11 cell line, which supports high level protein expression (Cho et al. Cytotechnology 2001, 37, 23-30). In the present study, we further demonstrated that HKB11 cells are suitable for high throughput expression (microgram scale) of genomic candidates in transient transfection system for in vitro evaluation of biological functions. HKB11 cells were also shown to support the production of milligram to gram quantities of protein drug candidates for in vivo evaluation of efficacy in various disease models. Stable HKB11 clones secreting high levels of a tissue factor (TF; 40-50 pg/c/d) and B-domain deleted recombinant factor VIII (BDDrFVIII; 5-10 microU/c/d) were derived under serum-free conditions. The specific productivity for these two proteins from the HKB11 cells was 10-fold greater than those from CHO cells derived under the similar conditions. In conclusion, we have demonstrated that the HKB11 cell line is well-suited for transient and long-term production of recombinant proteins.
J Biomed Sci. 2002 Nov-Dec;9(6 Pt 2):631-8.
Establishment of a human somatic hybrid cell line for recombinant protein production.
Cho MS, Yee H, Chan S.
Molecular and Cell Biology, Process Sciences, Biotechnology, Bayer Corporation, Berkeley, Calif 94701-1986, USA. myung-sam.cho.b@bayer.com
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.
MorphoSys, Bayer To Cross-License Technologies
Tuesday January 13, 2:01 am ET
Edited Press Release
FRANKFURT -(Dow Jones)- MorphoSys AG said Tuesday it has made an agreement with Bayer HealthCare (NYSE:BAY - News) for the cross-licensing of certain technologies.
Under the agreement, MorphoSys will receive the human cell line HKB 11 for production of HuCAL antibodies. MorphoSys will also receive the right to use the cell line for its own research and an option for the commercial production of antibodies using the HKB 11 cell line. In exchange, Bayer will switch its in- house R&D programs to the MorphoSys HuCAL GOLD antibody technology.
Additionally, MorphoSys will receive an installation fee from Bayer HealthCare.
The announcement builds on the existing agreement between the two companies, entered into in December 1999. In July 2001, the collaboration was extended to run through the end of 2005. The collaboration focuses on the use of human antibodies for application in the areas of therapy, diagnostics and target research. In the context of the agreement, MorphoSys receives annual license payments and can receive development-related milestone payments and royalties for marketed products.
"We are delighted to be expanding our collaboration with Bayer", commented Dr. Simon Moroney, Chief Executive Officer of MorphoSys AG. "This expansion further enhances our capabilities for the development of therapeutic antibodies and is an important component for our partnering strategy." |
