[Experimental study on promoting the engraftment of hematopoietic stem/progenitor cell by all-trans retinoic acid].
OBJECTIVE
To explore the effect of all-trans retinoic acid (RA) on the engraftment of unrelated umbilical cord blood stem/progenitor cell transplantation (UCBT) in murine model.


METHODS
1 x 10(6) and 0.5 x 10(6) nucleated cells (NC) from C57BL/6 (H-2(b)) fetal and neonatal peripheral blood (FNPB) were separately transfused into lethally cyclophosphamide (380 mg/kg, ip) treated BALB/C (H-2(d)) recipients, 15 mg.kg(-1).d(-1) and 5 mg.kg(-1).d(-1) RA (15 mg and 5 mg RA) were administrated respectively 2 days before and after UCBT. Hematopoiesis and immune recovery, graft versus host disease (GVHD), engraftment and survival rates were then observed.


RESULTS
Hematopoiesis and immune recovery occurred faster in RA treated than in untreated mice (P < 0.05). Acute GVHD was absent. The levels of engraftment were higher in both 15 mg and 5 mg RA treated mice than those in untreated controls (P < 0.05). In 1 x 10(6) NC transfused mice, 15 mg and 5 mg RA could significantly increased the 30 and 60 days survival rates from 41.67% (without RA) to 72.23% and 70.83%, respectively (P < 0.05). In 0.5 x 10(6) cells transfused mice, 15 mg and 5 mg RA increased the survival rate from 14.29% (without RA) to 42.86% and 43.48%, respectively (P < 0.05), which were comparable to that of being transfused 1 x 10(6) cells without RA treatment (P > 0.05).


CONCLUSIONS
RA enhances the engraftment of umbilical cord blood stem/progenitor cells in murine model for UCBT. This might provide an experimental evidence of RA in clinical UCBT.
Mai
Hui-rong
HR
Hematopoietic Stem Cell Transplantation Center, Department of Pediatrics, Sun Yet-sen Memorial Hospital, Sun Yet-sen University of Medical Sciences, Guangzhou 510120, China.
Huang
Shao-liang
SL
Xu
Hong-gui
HG
Fang
Jian-pei
JP
Wei
Jing
J
Huang
Wen-ge
WG
Chen
Feng-ying
FY
Guo
Fen-fen
FF
D000818:Animals; D036101:Cord Blood Stem Cell Transplantation; D005260:Female; D006085:Graft Survival / Q000187:drug effects; D006086:Graft vs Host Disease / Q000517:prevention & control; D018380:Hematopoietic Stem Cell Transplantation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D019172:Transplantation Conditioning; D014183:Transplantation, Heterologous; D014212:Tretinoin / Q000494:pharmacology*
D014212:Tretinoin