Induction of tolerance to mouse skin allograft by donor bone marrow-derived immature dendritic cells combined with rapamycin

Objective To investigate the synergic effects of donor bone marrow-derived immature dendritic cells combined with rapamycin on induction of tolerance to skin allograft in mice. Methods An allogenic skin transplantation model was established with the donors C57BL/6 mice and the recipients BALB/C mice. Recipients were divided into 4 groups ： control group （ no administration before or after skin transplantation） , rapamycin group （receiving rapamycin 1 mg/kg^-1·d^-1 by garage for consecutive 7 days after skin transplantation） ,immature DC group （receiving an injection of donor bone marrow-derived immature DC via tail vein before skin transplantation）, combined group （receiving an injection of donor bone marrow-derived immature DC via tail vein before transplantation and rapamycin 1 mg/kg^-1·d^-1 by garage for consecutive 7 days after transplantation）. The survival time of skin allograft was observed. Results The survival time of skin allograft in the groups of control, rapamycin, immature DC, and immature DC ± rapamyein was （6.9 ± 1.9 ）, （ 10.3 ± 3.0）, （ 17.0 ± 3.4 ）, and （ 20.8 ± 3.6 ） days respectively. Statistical analysis showed that there was significant difference among groups （ P 〈 0.05 ） ; Furthermore, S-N-K test showed that there was significant difference between every two groups. Conclusion There were synergic effects for donor bone marrow-derived immature dendritic cells and rapamycin in induction of tolerance to skin allograft in mice. Key words: Dendritic cells;  Rapamyein;  Immune tolerance;  Skin transplantation