Myoblast-based cardiac repair: xenomyoblast versus allomyoblast transplantation.
OBJECTIVE
We sought to investigate immune cell kinetics in relation to skeletal myoblast survival and heart function improvement after nonautologous skeletal myoblast transplantation in a rat model of myocardial infarction.


METHODS
One week after myocardial infarction, 208 Wistar rats were grouped into group 1 (n = 24, receiving 150 muL of medium only), group 2 (n = 24, receiving 150 muL of medium and cyclosporine [INN: ciclosporin]), group 3 (n = 40, human skeletal myoblast transplantation), group 4 (n = 40, human skeletal myoblast transplantation with cyclosporine treatment), group 5 (n = 40, rat skeletal myoblast transplantation), and group 6 (n = 40, rat skeletal myoblast transplantation with cyclosporine treatment). The hearts were harvested at 10 minutes and 1, 4, 7, and 28 days after cell transplantation. Skeletal myoblast survival was confirmed by means of immunohistochemical studies and quantified by using real-time polymerase chain reaction. Host immune responses were assessed by immunostaining for macrophages and CD4+ and CD8+ lymphocytes. Heart function was evaluated by means of echocardiographic analysis.


RESULTS
The majority of macrophages and lymphocytes infiltrated in the acute phase (from day 1 to day 7) and then subsided by day 28. The donor skeletal myoblasts survived and differentiated well in all skeletal myoblast transplantation groups. Allogeneic skeletal myoblasts showed a superior survival rate than xenogeneic skeletal myoblasts (P < .01). Cyclosporine inhibited the infiltration of the immunocytes, enhanced skeletal myoblast survival, and improved heart performance compared with that seen in the groups not receiving cyclosporine treatment (P < .05).


CONCLUSIONS
Allomyoblasts survive better than do xenomyoblasts after transplantation into infarcted myocardium. After inhibition of immunocyte infiltration by means of immunosuppressive treatment, skeletal myoblast survival is enhanced, with improved heart performance. These findings suggest the feasibility of nonautologous myoblast transplantation with immunosuppressive treatment.
Guo
Changfa
C
Department of Surgery, National University of Singapore, Singapore.
Haider
Husnain Kh
HKh
Shim
Winston S N
WS
Tan
Ru-San
RS
Ye
Lei
L
Jiang
Shujia
S
Law
Peter K
PK
Wong
Philip
P
Sim
Eugene K W
EK
D000818:Animals; D017690:Cell Transplantation; D016572:Cyclosporine / Q000494:pharmacology; D004195:Disease Models, Animal; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D007108:Immune Tolerance / Q000187:drug effects; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008297:Male; D032446:Myoblasts / Q000276:immunology / Q000637:transplantation*; D009203:Myocardial Infarction / Q000628:therapy*; D051381:Rats; D017208:Rats, Wistar; D014183:Transplantation, Heterologous / Q000276:immunology; D014184:Transplantation, Homologous / Q000276:immunology
D007166:Immunosuppressive Agents; D016572:Cyclosporine