A retrovirus carrying an MDR1 cDNA confers multidrug resistance and polarized expression of P-glycoprotein in MDCK cells.

Abstract

A full-length cDNA for the human multidrug resistance gene 1 (MDR1) has been inserted into a retroviral vector containing a murine Harvey sarcoma virus from which the viral oncogene was deleted. Ecotropic and amphotropic virus was produced after transfection of this vector into psi-2 and PA-12 packaging cell lines. This virus conferred the full phenotype of multidrug resistance on mouse and human cell lines. Viral titers of up to 2 X 10(5) drug-resistant colonies per ml were observed. Infected cells became resistant to colchicine, vinblastine, doxorubicin, VP16 (etoposide), and puromycin, but not cisplatin, indicating that the presence of the human MDR1 gene is sufficient to cause multidrug resistance. When the dog kidney cell line MDCK was infected with the MDR1 virus, P-glycoprotein was expressed in a polarized manner on the upper surface of the cells, showing that the cloned cDNA also encodes information for polarized expression of P-glycoprotein. The MDR1 virus should be useful for introducing this drug resistance gene into a variety of cell types for biological experiments in vitro and in vivo.

Drug selection of MDR1-transduced hematopoietic cells ex vivo increases transgene expression and chemoresistance in reconstituted bone marrow in mice

“…52 This MDR1 cDNA contains a point mutation (G185V) which confers preferential resistance to colchicine. 45,46 By transfection of pHaMDR1/A into PA317 packaging cells, a virus producing cell clone, designated MA1, was generated.…”

Feasibility of multidrug resistance (MDR-1) gene transfer in patients undergoing high-dose therapy and peripheral blood stem cell transplantation for lymphoma

“…The amphotropic retroviral producer cell line A12M1 26 which derives from the packaging cell GP+envAM12 27 and the MDR-1 vector pHaMDR-1 28 was used in these studies. Clinical grade supernatants (provided by Genetix Pharmaceuticals, Cambridge, MA, USA) were produced in Iscove's modified Dulbecco's medium (IMDM) with 20% fetal calf serum (Magenta, Rockville, MD, USA).…”

MDA435/LCC6 and MDA435/LCC6MDR1: ascites models of human breast cancer

“…MDA-MB-435 is one of the few human breast cancer cell lines that produces reproducible lung metastases from solid tumours (Price et al, 1990;Meschter et al, 1992 al., 1988). Cells were infected with virus by the addition of PA-12 cell supernatant (Pastan et al, 1988) to exponentially proliferating MDA435/LCC6 cells twice, with a 24 h gap between each addition. Transduced cells (1 x 106) were then selected in the presence of either 100 ng ml-' or 400 ng ml-' colchicine for a period of at least 3 months.…”