Background stem cells （B infarction （MI controversial. Stem cells have MSCs） derived ）. The in vivo c Poor moderate multilineage differentiation capacity, which makes bone marrow mesenchymal relatively easy and provides a promising alternative treatment for myocardial ardiac differentiation and functional effects of unmodified BMSCs after MI are survival benefits of BMSCs-implanted rats were caused by incomplete electromechanical integration induced by infarcted myocardium. This study was to therapeutic efficacy in MI. Methods tissue heterogeneity between myocytes and engrafted BMSCs in the investigate whether connexin43 （Cx43） modified BMSCs improve Lentivirus mediated Cx43 gene was transfeeted into human BMSCs. Flowcytometry was used to detect cell surface markers of BMSCs before and after Cx43 transfection. Cx43 expression levels were detected by fluorescent microscope and western blotting. Post-MI intramyocardial injection of 1 x 106 stem ceils was compared with injection of medium alone echocardiography. Results Heart function was detected by Cx43 of BMSCs could be effectively overexpressed by lentivirus mediated gene transfection. Flowcytometry showed that after Cx43 overexpression, the surface markers of BMSCs were greatly decreased. Immunofluorescent microscopy revealed GFP-posotive transplanted BMSCs among the MI area. The Cx43-BMSCs-treated heart, assessed by echocardiography, improved ejection fraction compared with PBS- and mock-BMSCs-treated hearts （P 〈 0.01）. Conclusions Lenti-Cx43 can be effectively transfected into BMSCs. Cx43 may act as a potential target for improving the therapeutic efficacy of BMSCs in ischaemic heart disease.
