Objective    To investigate the expression of exogenous human telomerase reverse transcriptase (hTERT) in the human mesenchymal stem cells (hMSCs) and detect the effect of the gene on cellular telomerase activity and proliferative capacity.     Methods    The plasmid pLXSN-hTERT was constructed and identified by sequencing and enzyme digestion. Then the plasmid was packaged in PT67 and masculine clone cells were screened. The clone was co-cultured with hMSCs. The telomerase activity in the hMSCs was detected by TRAPEZE. The cell cycle was detected by flow cytometry and the growth of hMSCs were observed under inverted microscope.     Results    A recombinant hTERT-retroviral vector was successfully constructed

and a packaging cell line producing PT67-pLXSN-hTERT virus was established. An hMSCs-TERT cell population was obtained when hMSCs was transfected by means of co-culturing which with the PT67-pLXSN-hTERT virus packaging cells. Compared with the un-infected ones

hTERT-hMSCs cell population acquired stronger telomerase activity

higher hTERT-positive cell ratio

longer cell surviving time and more powerful proliferative capacity

and maintained good growth condition without obvious morphological changes even until passage 46.     Conclusion    The hTERT gene can be well introduced into hMSCs mediated by retroviral vector

hence prominently increasing the cellular expression of hTERT

telomerase activity and proliferative capacity

and ultimately

delaying cell senescence.