background: phic31 integrase is a dna site-specific recombinase integrates dna into the chromosomes between the two sites of attb and attp. several pseudo attps have been identified in mammalian genomes with critical features for long-term expression of transgene. in this manuscript, we report a novel intrinsic pseudo attp site named chol1 in the chinese hamster genome implementing an inverse p...

Background: The optimization of bioprocess conditions towards improved growth profile and productivity yield is considered of great importance in biopharmaceutical manufacturing. Peptones as efficient sources of nutrients have been studied for their effect on media development however, their role on metabolic pathway is not well understood. Methods: In the present study, the effect of different...

A Chinese hamster ovary cell mutant defective in the receptor-mediated endocytosis of several unrelated ligands (Robbins, A. R., S. S. Peng, and J. L. Marshall, 1983, J. Cell Biol., 96:1064-1071) failed to accumulate iron provided in the form of diferric transferrin. Analysis of the steps of the transferrin cycle indicated that binding and internalization of transferrin proceeded normally in mu...

Epstein-Barr virus (EBV) infects human B lymphocytes and epithelial cells. We have compared the requirements for EBV glycoprotein-induced cell fusion between Chinese hamster ovary effecter cells and human B lymphoblasts or epithelial cells by using a virus-free cell fusion assay. EBV-encoded gB, gH, gL, and gp42 glycoproteins were required for efficient B cell fusion, whereas EBV gB, gH, and gL...

Adriamycin cytotoxicity and membrane permeability to Adriamycin were studied at elevated temperatures in a drug-sensitive Chinese hamster ovary cell line and in a pleiotropic drug-resistant mutant to determine whether hyperthermia can overcome this form of acquired drug resistance. In drug-sensitive cells Adriamycin cytotoxicity, measured by colony survival studies, increased at temperatures as...

The Chinese hamster ovary cell line xrs-1 is hypersensitive to gamma-radiation. This sensitivity has been attributed to an inability of this cell line to efficiently repair gamma-ray induced double-strand breaks (DSBs). We have recently reported that xrs-1 is also sensitive to topoisomerase II inhibitors that stabilize the cleavable complex. In this study, we have investigated the basis of this...

The Chinese hamster ovary cell line xrs-1 is hypersensitive to yradiation. This sensitivity has been attributed to an inability of this cell line to efficiently repair T-ray induced double-strand breaks (DSBs). We have recently reported that xrs-1 is also sensitive to topoisomerase II inhibitors that stabilize the cleavable complex. In this study, we have investigated the basis of this sensitiv...

Twenty Serratia marcescens isolates from clinical specimens were examined for their cytotoxic activity on four cell lines (HEp-2, Vero, CHO, J774). Most of the isolates were found to be cytotoxic to CHO (70%), Vero (75%) and HEp-2 cells (90%). CHO cells were the most sensitive to cell-free supernatants, followed by HEp-2 and Vero cells. Two strains produced cytotonic toxins which caused elongat...

Author details Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, 602-8566, Kamigyo, Kyoto, Japan. Emergency Medicine, Kamigyo, Japan. Cardiovascular Surgery, Kyoto Prefectural University of Medicine, Kamigyo, Kyoto, Japan. Department of Anesthesiology, Kansai Medical University, Hirakata, Japan. Department of Statistical Genetics, Kyoto University, Kamigyo, ...

Mitomycin C (MMC), a bifunctional alkylating agent, requires metabolic reduction to become biologically active. We have identified a series of genetically related Chinese hamster ovary cell lines which span approximately three orders of magnitude in the concentration of MMC required for cell killing. Many mechanisms, including drug transport, drug activation, drug detoxification, and the elimin...