MDR1 gene expression in the myelomonocytic progeny of CD34+ peripheral blood progenitor cells (PBPC) after a 96-hour Transwell transduction period in fibronectin-coated wells.

Aliquots of MDR1-transduced and mock-transduced CD34+ PBPC samples were cultured for 10 days in liquid medium containing a myeloid differentiation-inducing cytokine mixture. Rh-123 efflux in the progeny of MDR1-transduced and mock-transduced CD34+ PBPC was determined by fluorescence-activated cell separation (FACS) analysis without or with inclusion of the P-glycoprotein inhibitor cyclosporine (CsA).