[Transplantation of 3H-thymidine-labeled human bone marrow-derived mesenchymal stem cells in mdx mice].
OBJECTIVE
To investigate the feasibility of using human bone marrow-derived mesenchymal stem cells (hBM- MSCs) for repairing the skeletal muscle sarcolemma lesions in mdx mice and characterize the distribution of the transplanted hBM-MSCs.


METHODS
Eighteen 8- to 10-week-old immunosuppressed mdx mice received transplantation with 1x10(7) of hBM-MSCs (the fifth passage) with 3H-thymidine (3H-TdR) labeling by injection of the cells into the tail vein. The mice were killed at 24 h, 48 h, 2 weeks, and 1, 2 and 4 months after the transplantation, respectively, to measure the radioactivity in the tissues and organs. Dystrophin expression on the sarcolemma was detected by immunofluorescence analysis.


RESULTS
One month after transplantation, the mice with cell transplantation showed greater radioactivity in most of the tissues and organs than the control mice, especially in the bone marrow, liver and spleen. The radioactivity was then gradually lowered but in the skeletal muscle, the radioactivity increased progressively since 2 weeks after transplantation, reaching the peak of 27.65+/-3.53 Bq/mg at 1 month. Compared with that in the control mice, the radioactivity in the bone marrow and skeletal muscle was persistently higher in mice with cell transplantation 1 month after transplantation. No dystrophin-positive cells were found in the mdx mice at 2 weeks but detected at 1 month. The percentage of dystrophin-positive fibers in each section ranged from a 6.6% (1 month) to 8.9% (4 months).


CONCLUSIONS
hBM-MSCs engrafted in immunosuppressed mdx mice may differentiate into skeletal muscle cells to repair the pathological lesion of the skeletal muscle sarcolemma. The hBM-MSCs reside mainly in the bone marrow, liver and spleen in the early stage following transplantation, homing into the bone marrow and skeletal muscle later.
Liu
Tai-yun
TY
Department of Neurology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510089, China. ltylxlf@gzsums.edu.cn
Li
Jing-lun
JL
Yao
Xiao-li
XL
Dong
Qun-wei
QW
Su
Quan-xi
QX
Feng
Shan-wei
SW
Li
Cai-ming
CM
Zeng
Ying
Y
Liu
Zu-guo
ZG
Zhang
Cheng
C
Liu
Chang-zheng
CZ
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D016189:Dystrophin / Q000378:metabolism; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D051379:Mice; D018101:Mice, Inbred mdx; D009137:Muscular Dystrophy, Animal / Q000601:surgery*; D012508:Sarcolemma; D013194:Staining and Labeling; D013936:Thymidine / Q000032:analysis; D014183:Transplantation, Heterologous; D014316:Tritium
D016189:Dystrophin; D014316:Tritium; D013936:Thymidine