Transfected cells Chinese hamster ovary

Covitz, K. M., G. L. Amidon, and W. Sadee. Human dipeptide transporter, hPEPTl, stably transfected into Chinese hamster ovary cells. Pharm. Res. 1996, 13, 1631-1634. 

EPO is present in serum and (at very low concentrations) in urine, particularly of anaemic individuals. This cytokine/hormone was first purified in 1971 from the plasma of anaemic sheep, while small quantities of human EPO was later purified (in 1977) from over 2500 litres of urine collected from anaemic patients. Large-scale purification from native sources was thus impractical. The isolation (in 1985) of the human EPO gene from a genomic DNA library, facilitated its transfection into Chinese hamster ovary (CHO) cells. This now facilitates large-scale commercial production of the recombinant human product (rhEPO), which has found widespread medical application. 

As an extension of the HA film approach, Yun and coworkers [32] synthesized hyaluronan microspheres using the chemistry described above, but the synthesis was completed in emulsion in one step, yielding 5- to 20-pm microspheres. These microspheres were found to be biodegradable and released three times more pDNA when incubated with hyaluronidase in PBS (phosphate buffered saline) solution (vs enzyme-free PBS). As in the case of films, DNA release from the microspheres was dependent on the DNA loading. DNA-HA microspheres were not directly used for transfection instead, DNA obtained from release experiments was used in transfection of Chinese hamster ovary (CHO) cells using Lipofectamine. The relative levels of transfection over time had the same trend as DNA release from the DNA-HA microspheres and confirmed that released DNA is bioactive. 

Binding assays using [ Hja-DPDPE (DOR), [ H]U69,593 (KOR) and [ H]DAMGO (MOR) in recombinant human opioid receptors transfected into Chinese hamster ovary cells... 

Transporter, hPEPTl, Stably Transfected Into Chinese Hamster Ovary Cells. 

To test the ability of the artificial mRNA to support GLP-1 expression in whole cells, Chinese hamster ovary cells were transfected with artificial mRNA by electroporation. Twelve hours after transfection, cells were harvested and GLP-1 was determined by sandwich ELISA. mRNA derived from both the 130-nt and the 170-nt RNA supported GLP-1 expression, albeit weakly, whereas control RNA with no cap 1 or poly(A) tail did not. 

FIGURE 2.11 Receptor-occupancy curves for activation of human calcitonin type 2 receptors by the agonist human calcitonin. Ordinates (response as a fraction of the maximal response to human calcitonin). Abscissae (fractional receptor occupancy by human calcitonin). Curves shown for receptors transfected into three cell types human embryonic kidney cells (HEK), Chinese hamster ovary cells (CHO), and Xenopus laevis melanophores. It can be seen that the different cell types lead to differing amplification factors for the conversion from agonist receptor occupancy to tissue response. 

Avidor-Reiss T, Bayewitch M, Levy R, Matus-Leibovitch N, Nevo I, Vogel Z. Adenylylcyclase supersensitization in mu opioid receptor transfected Chinese hamster ovary cells following chronic opioid treatment. J Biol Chem 1995 270 29732-29738. 

Human delta opioid receptor Functional studies on stably transfected Chinese hamster ovary cells after acute and chronic treatment with the selective non-peptidic agonist SNC-80. J Pharmacol Exp Ther 1996 278 1083-1089. 

Protein-protein interactions between heterodimeric protein pairs that form only transient interactions can be detected, y-secre-tase is presenilin-1 (PS1) dependent [51-53]. PS1 is a 467-amino acid, 9-transmembrane domain protein. Over 100 documented single point mutations are known to cause autosomal-dominant familial AD (FAD) [54], in which the ratio of the more fibrilogenic variety of A ft (A/142) to the less fibrilogenic variety (A/140) is increased. Chinese hamster ovary (CHO) cells were stably transfected with human APP and either wild type or mutant PS1 [4, 55]. 

In this assay, rhuMAbs produced in transfected Chinese hamster ovary (CHO) cells were analyzed using a commercially available SDS-protein analysis... 

Biopharmaceutical quantities of EPO are produced with recombinant cells. This is achieved through the isolation of the human gene that codes for EPO and transfection of the gene into cell lines such as Chinese hamster ovary cells (see Section 10.5). The product is called rhEPO—recombinant human EPO. EPO is normally administered subcutaneously and is generally well tolerated by patients. 

Ishizuka, T., Murata, N., Kanda, T., Kobayashi, I., Ohta, H., Ui, M. and Okajima, F., 1999, Comparison of intrinsic activities of the putative sphingosine 1-phosphate receptor sub-types to regulate several signaling pathways in their cDNA-transfected Chinese hamster ovary cells. J. Biol. Chem. 274 23940-23947. 

Clinical trials have demonstrated excellent efficacy with recombinant human factor VIII concentrates available as Recombinate and Kogenate. These recombinant factor VIII products are purified from the cell culture of plasmids, not viral DNA-transfected hamster cells and therefore do not express viral sequences. The addition of human serum albumin for stabilization, constitutes the sole possible source for human viral contamination. More recently recombinant factor IX has been genetically engineered by insertion of the human factor IX gene into a Chinese hamster ovary cell line. It has been proved to be safe and effective in the treatment of patients with hemophilia B. 

Rundfeldt, C. and Netzer, R. The novel anticonvulsant retigabine activates M-current in Chinese hamster ovary-cells transfected with human KCNQ2/3 subunits, Neuroscience Letters 2000, 282, 73-76. 

Garcia, M., Sakamoto, K., Shigekawa, M., Nakanishi, S., Ito, S. Multiple mechanisms of arachidonic acid release in Chinese hamster ovary cells transfected with cDNA of substance P receptor, Biochem. Pharmacol. 1994, 48, 1735-1741. 

Mochizuki, O. N., Nakajima, Y., Nakanishi, S., Ito, S. Characterization of the substance P receptor-mediated calcium influx in cDNA transfected Chinese hamster ovary cells. A possible role of inositol 1,4,5-triphosphate in calcium influx, J. Biol. Chem. 1994, 269, 9651-9658. 

Pan Z., Damron D., Nieminen A.L., Bhat M.B., and Ma J. 2000 Depletion of intracellular Ca2+ by caffeine and ryanodine induces apoptosis of Chinese hamster ovary cells transfected with ryanodine receptor. J Biol Chem 275, 19978-19984. 

Cowen DS, Molinoff PB, Manning DR. 5-Hydroxytryptamine1A receptor-mediated increases in receptor expression and activation of nuclear factor-kappaB in transfected Chinese hamster ovary cells. Mol Pharmacol 1997 52 221-226. 

---