Objective:To study the survival and the cardiac differentiation of mesenchymal stem cells from human fetal livers(FMSCs) after being transplanted into infarted rat myocardium. Methods:FMSCs were cultured from human fetal livers

the average age of which was 9 days. The infarction model was built by the ligation of left anterior descending artery and 3.5×106cells were transplanted into infarction area by direct injection one week after ligation. Rats were killed at 1 and 2 weeks after transplantation

and hearts were collected for the examination of the cells’ survival and differentiation toward cardiac tissue by fluorescent in situ hybridization(FISH)and immunohistochemistry staining. Results:The FACS results showed that FMSCs expressed antigen CD29

CD44

CD166

SH2(CD105)

SH3 and SH4

but did not express CD14

CD34 and CD45.The transplanted cells survived at 7th day after transplanted

but dissappeared at 14th day. No cardiac differentiation was observed during this period. Conclusion:The cells we cultured are testified as FMSCs by their phenotypic expression

and FMSCs could survive for a short period after transplanted into rat heart infarction model

but no cardiac differentiation is induced.