ObjectiveTo transplant the autologous mesenchymal stem cells(MSCs) carrying human hyperpolarization activated cyclic nucleotide gated channel 2 (hHCN2) gene into the His-bundle in porcine model of complete heart block (CHB), so as to assess the possibility of establishing autologous biological pacing. MethodsWe constructed the recombinant adenovirus containing hHCN2 gene to transfect the porcine MSCs. After autotransplantation into the His-bundle in CHB model, the genetically-altered MSCs were tested for their ability to provide a stable and catecholamine-responsive heart rhythm. Histological and immunofluorescence analyses were also performed for the myocardium of the injection site. ResultsRecombinant adenovirus pAd.hHCN2 was successfully constructed. Porcine MSCs were transfected by the adenovirus. After autotransplantation, transgenic MSCs significantly enhanced the heart rates in porcine CHB model compared with the control group (P<0.01), and the cardiac rhythms in the transgenic MSC group were catecholamine responsive. Tissues obtained from the transplanted heart sites showed that the MSCs survived in the myocardium and overexpressed hHCN2 protein. ConclusionTransplantation of autologous genetically-altered MSCs into the His-bundle in porcine CHB model can serve as a short-term catecholamine-responsive biological pacemaker.