A new multiple drug-resistant Chinese hamster ovary cell line, ( IK )SMRs, has been isolated which demonstrates a direct correlation between reduced cellular topoisomerase II activity (5-fold reduction) and a low level of resistance (3to 7-fold) to topoisomerase II inhibitors. This cell line, initially selected for resistance to 9-(4,6-0-ethylidene-i8-D-glucopyranosyl)-4'-demethylepipodophyllot...

A sterol-requiring mutant has been isolated from mutagenized Chinese hamster ovary cells. This mutant grows normally only when cholesterol is present in the medium. Cell lysis occurs within 3 days in the absence of cholesterol. The frequency of reversion of this mutant to prototrophic growth is low (less than or equal to 10(-6). Whole cell pulse experiments with [14C]acetate or [3H]mevalonate i...

We searched for novel Chinese hamster ovary (CHO) cell mutants defective in peroxisome biogenesis by an improved method using peroxisome targeting sequence (PTS) of Pex3p (amino acid residues 1–40)-fused enhanced green fluorescent protein (EGFP). From mutagenized TKaEG3(1–40) cells, the wild-type CHO-K1 stably expressing rat Pex2p and of rat Pex3p(1–40)-EGFP, numerous cell colonies resistant to...

Biochemical and physiochemical properties of recombinant human antithrombin III were examined. This protein, produced in Chinese hamster ovary cells, showed a conformation apparently identical with the natural product isolated from human plasma when examined by circular dichroism, UV absorbance, and fluorescence spectroscopy. Comparison of the NH2-terminal sequences of recombinant and human pla...

For the manufacturing of complex biopharmaceuticals using bioreactors with cultivated mammalian cells, high product concentration is an important objective. The phenotype cells in a reactor plays role. Are clonal cell populations showing cell-specific growth rates more favorable than lines higher productivities or vice versa? Five Chinese hamster ovary were analyzed based on data 3-month-stabil...

To further understand the relationships between DNA damage, DNA repair, and cellular end points such as survival and mutation, the repair capacity of a DNA repair-deficient mutant (strain UV-20) of Chinese hamster ovary cells was characterized in response to DNA cross-linking agents. This mutant, previously shown to be hypersensitive to killing by both ultraviolet light and the cross-linking ag...

Vinca alkaloids are important chemotherapeutic agents, and their pharmacokinetic properties display significant interindividual variations, possibly due to CYP3A4-mediated metabolism. We have evaluated the relevance of this metabolism for the chemotherapeutic and the toxicological properties of these drugs. Analysis was performed using Chinese hamster ovary cell lines that expressed either CYP2...