[Transfer and identification of multidrug resistance gene in mesenchymal stem cells derived from human placenta].

OBJECTIVE: To explore the feasibility and safety of mdr1 gene transferred into placenta derived mesenchymal stem cells (P-MSCs) by reconstructed retroviral vector. METHODS: Human P-MSCs were isolated and expanded by Percoll density gradient and then transduced repeatedly by reconstructed retroviral vector containing mdr1 gene. The transfection and expression of mdr1 gene was detected by reverse transcription-polymerase chain reaction (RT-PCR) and fluorescence-activated cell sorting (FACS). Meanwhile, the biological features of mdr1-MSCs were identified and analyzed. RESULTS: The expression of mdr1mRNA was found in transfected cells. The expression of P-glycoprotein (P-gp) encoded by mdr1 gene was (27.6 ± 5.1)% in the transfected P-MSCs cells versus (0.4 ± 0.1)% in the non-transfected P-MSCs cells (t = 14.291, P < 0.01). The percent of P-MSCs at quiescent phase (G0/G1 phase) was around 95.40% and it was in accord with the characterization of stem cells. The mdr1-MSCs exhibited typical ultrastructures of low-differentiated stem cells. Moreover, they still retained the potency of adipogenic and osteogenic differentiation in the presence of appropriate conditioned media. CONCLUSION: A stable expression of P-gp may be obtained by reconstructed retroviral-mediated transfection in vitro. And transfected MSCs retain the characteristics of stem cells.