Quantitative analysis of survival of transplanted smooth muscle cells with real-time polymerase chain reaction.
BACKGROUND
Cell transplantation improves heart function after myocardial infarction. This study investigated the survival of implanted cells in normal and infarcted myocardium.


METHODS
Male rat aortic smooth muscle cells were cultured. For the in vitro study, male smooth muscle cells mixed with female smooth muscle cells or male smooth muscle cells injected into a piece of female rat myocardium were used to evaluate the accuracy of quantitative real-time polymerase chain reaction to measure Y chromosomes. For the in vivo study, 2 million live or dead male smooth muscle cells were injected into normal or infarcted female myocardium. At 1 hour and 1 and 4 weeks after transplantation, hearts, lungs, and kidneys were harvested for measurement of Y chromosomes.


RESULTS
In vitro, the accuracy of polymerase chain reaction measurement was excellent in cultured cells (r2 = 0.996) and the myocardium (r2 = 0.786). In vivo, 1 hour after 2 x 10(6) cell implantation, live cell numbers decreased to 1.0 +/- 0.2 x 10 6 and 1.1 +/- 0.3 x 10(6) , and dead cell numbers decreased to 0.9 +/- 0.2 x 10(6) and 0.8 +/- 0.2 x 10(6) in the normal and infarcted myocardium, respectively (P < .01 for all groups). Lungs and kidneys contained 8.5% and 1.5% of the implanted cells, but no cells were detected at 1 week. At 1 week, no dead smooth muscle cells were detected in the normal or infarcted myocardium. The numbers of live cells at 1 and 4 weeks were 0.48 +/- 0.06 x 10(6) and 0.27 +/- 0.07 x 10(6) in normal myocardium and 0.29 +/- 0.08 x 10(6) and 0.18 +/- 0.05 x 10(6) in infarcted myocardium.


CONCLUSIONS
One hour after implantation, only 50% of smooth muscle cells remained in the implanted area. Some implanted cells deposited in other tissue. Implanted cell survival progressively decreased during the 4-week study.
Yasuda
Tamotsu
T
Division of Cardiovascular Surgery, Toronto General Research Institute, Toronto General Hospital, Division of Cardiac Surgery, University of Toronto, Toronto, Ontario, Canada.
Weisel
Richard D
RD
Kiani
Chris
C
Mickle
Donald A G
DA
Maganti
Manjula
M
Li
Ren-Ke
RK
D000818:Animals; D000963:Antimetabolites; D001921:Brain / Q000473:pathology; D001973:Bromodeoxyuridine; D016923:Cell Death; D002470:Cell Survival; D002478:Cells, Cultured; D004247:DNA / Q000235:genetics; D005260:Female; D006085:Graft Survival; D007668:Kidney / Q000473:pathology; D008168:Lung / Q000473:pathology; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D009203:Myocardial Infarction / Q000601:surgery; D009206:Myocardium / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000637:transplantation*; D016133:Polymerase Chain Reaction; D051381:Rats; D011917:Rats, Inbred Lew; D013997:Time Factors; D014998:Y Chromosome / Q000235:genetics
D000963:Antimetabolites; D004247:DNA; D001973:Bromodeoxyuridine