The pattern of preferential DNA repair of UV-induced pyrimidine dimers was studied in repair-deficient Chinese hamster ovary (CHO) cells transfected with the human excision repair gene, ERCC-1. Repair efficiency was measured in the active dihydrofolate reductase (DHFR) gene and in its flanking, non-transcribed sequences in three cell lines: Wild type CHO cells, a UV-sensitive excision deficient...

CD14-expressing Chinese hamster ovary (CD14-CHO) cells, established by transfection of human CD14 DNA, acquired high responsiveness to lipopolysaccharide (LPS) through membrane-bound CD14 expression. LPS induced DNA synthesis and activated a series of mitogen-activated protein (MAP) kinases, extracellular signal-regulated kinase 1/2 (Erk1/2), p38, and c-Jun N-terminal kinase/stress-activated pr...

BACKGROUND The critical role of interleukin-7 (IL-7) in homeostatic proliferation and T cell survival has made it a promising cytokine for the treatment of various clinical conditions, especially those associated with lymphopenia. METHODS In the present study we expressed recombinant human interleukin-7 (rhIL-7) in Chinese hamster ovary (CHO)-K1 cells. CHO-K1 cells were stably transfected wit...

The aim of this study was to assess the suitability of amiloride, rhodamine 6G and rhodamine 123 as nonradioactive substrates for characterizing hOCT2 using CHO cells. The uptake characteristics of these compounds were compared in wild-type (WT) and human organic cation transporter 2 (hOCT2)-stably transfected Chinese Hamster Ovary (CHO) cells. All the compounds were accumulated by the CHO-hOCT...

We have reported previously the isolation and characterization of a Chinese hamster ovary cell line, designated CHO-Chl1, which exhibits resistance to bifunctional nitrogen mustards while maintaining sensitivity to a range of other alkylating agents and chemotherapeutic drugs. This enhanced drug resistance is associated with a greater than 40-fold in crease in the level of expression of an alph...

Background: The demand for producing recombinant therapeutic proteins by mammalian cell lines, such as Chinese hamster ovary (CHO) cells, continues to grow. Significant achievements in process optimization including development of cell culture strategies for largescale and cost-effective production have been made. Fetal bovine serum (FBS) is an often essential growth supplement and yet most cos...

We reported previously that Muc1 mucin on the epithelial cell surface is an adhesion site for Pseudomonas aeruginosa (Lillehoj EP, Hyun SW, Kim BT, Zhang XG, Lee DI, Rowland S, and Kim KC. Am J Physiol Lung Cell Mol Physiol 280: L181-L187, 2001). The present study was designed to identify the adhesin(s) responsible for bacterial binding to Muc1 mucin using genetic and biochemical approaches. Ch...

The L1 adhesion molecule plays an important role in axon guidance and cell migration in the nervous system. L1 is also expressed by many human carcinomas. In addition to cell surface expression, the L1 ectodomain can be released by a metalloproteinase, but the biological function of this process is unknown. Here we demonstrate that membrane-proximal cleavage of L1 can be detected in tumors and ...

The juxtamembrane region of the insulin receptor (IR) beta-subunit contains an unphosphorylated tyrosyl residue (Tyr960) that is essential for insulin-stimulated tyrosyl phosphorylation of some endogenous substrates and certain biological responses (White, M.F., Livingston, J.N., Backer, J.M., Lauris, V., Dull, T.J., Ullrich, A., and Kahn, C.R. (1988) Cell 54, 641-649). Tyrosyl residues in the ...

One of the main problems in the culture of Chinese Hamster Ovary (CHO) cells continues to be the inability to maintain the viability of the cultures over an extended period of time. The rapid decline in viability at the end of the culture is exacerbated by the absence of serum. In trying to reduce the extent of death in these cultures, we first tried to determine the mode of death. We found tha...