ABSTRACT
Objective To study the safety and effect of the umbilical cord blood(UCB)-derived mesenchymal stem cells(MSCs)on apoptosis of human cardiomyocytes(HCM). MethodsUCB was collected at the time of delivery with informed consent obtained from 10donors.The UCB-derived MSCs were treated with 5-azaserube(5-AZA)and were further induced to differentiate into cardiomyocytes.Telomerase activity,G-banding patterns of chromosomal karyotypes,tumor formation in nude mice,RT-PCR,and the effect of inhibiting apoptosis of HCM were investigated. ResultsMSCs derived from UCB were differentiated into cardiomyocytes in vitro,which possessed telomerase activity after 5-AZA induction,and no abnormal chromosomal karyotypes were observed.Expression of p53,cyclin A,cdk2,β-actin,C-fos,h-TERT and c-myc were similar in MSCs before and after 5-AZA treatment.There was no tumor formation in nude mice after injection of UCB-derived MSCs.UCB-derived MSCs significantly inhibited apoptosis of HCM. ConclusionUCB-derived MSCs are a valuable,safe and effective source of cell-transplantation treatment.