[Effects of ectomesenchymal stem cells on hematopoiesis after total body irradiation].
OBJECTIVE
To investigate the effects of ectomesenchymal stem cells on hematopoiesis after total body irradiation in rats.


METHODS
The primary ectomesenchymal stem cells were isolated from E11.5 SD fetal mandibular processes by 2.5 g/L trypsin and cultured with DMEM/F12. The morphology and growth rate were observed by inverted microscope. Eighty SD male rats randomly divided into ectomesenchymal stem cells group (n = 20), fibroblast group (n = 20), saline group (n = 20) and control group (n = 20), the first three groups were irradiated with 60Co gamma rays at 6. 0 Gy. The number of their bone marrow nucleated cells was counted after 4 weeks; the forming ability of colony-forming unit-granulocyte macrophage (CFU-GM) and histopathology of bone marrow were also observed.


RESULTS
The cultured cells displayed monolayer growth and fibroblast-like with 2-4 processes. The ectomesenchymal stem cells could increase the number of bone marrow nucleated cells and peripheral blood white cell count, and improve the forming ability of CFU-GM. After 4 weeks of transplantation, the number of the peripheral blood white cells in group A was more than that in groups B and C (P < 0.05), the contents of Hb in groups A and D was significantly higher than those in groups B and C (P < 0.05). After 4 weeks, the bone marrow nucleated cells in group A were significant more than those in groups B and C (P < 0.01); CFU-GM in groups A and D was higher than that in groups B and C (P < 0.01).


CONCLUSIONS
Ectomesenchymal stem cells have characteristics of stem cells. It may improve hematopoiesis recovery of irradiated rats.
The Center for Tissue Engineering, College of Stomatology, the Fourth Military Medical University, Xi'an Shaanxi 710032, P R China.
Rui
R
Yang
Yan
Y
Jin
Xin
X
Nie
Zeyuan
Z
Zhou
D000818:Animals; D001853:Bone Marrow; D002452:Cell Count; D004475:Ectoderm / Q000166:cytology; D005720:Gamma Rays; D055014:Granulocyte-Macrophage Progenitor Cells; D006412:Hematopoietic Stem Cells / Q000528:radiation effects*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells; D051381:Rats; D017207:Rats, Sprague-Dawley; D014916:Whole-Body Irradiation