[Study on the induction of skin transplantation tolerance against rejection in mice by third-party dendritic cells loaded with donor's antigens].

Objective: To investigate whether the third-party dendritic cells (DC) incubated with donor's antigens possess the similar immune functions with donor derived immature DC.

Methods: Female C57 BL/6, BALB/c and Kunming mice were used as skin transplant donors, recipients and third-party, respectively. Forty BALB/c mice were randomly divided into A (normal control), B (cyclophosphamide administration), C (CTX and donor derived immature DC), D (CTX and third-party immature DC), E (CTX and third-party DC loaded with donor's antigens) groups, with 8 mice in each group. The mice in group B, C, D and E were given CTX (200 mg/Kg) 4 days before operation, while those in group A were given equivalent amount of normal saline(NS). Then in group C, D and E, DC at a dose of 1 x 10(7)/ml were intraperitoneally injected with 2 days before grafting and 12 days after operation, but the mice in group A and B were given NS in the same manner. Mean survival time (MST) of skin grafts was recorded, and biopsies of grafts on 5 and 10 post-operation days (POD) were harvested for histologic examination.

Results: Compared with group A [(16.1 +/- 3.5)d], MST of skin grafts in group C [(38.3 +/- 7.7) d] and E [(34.9 +/- 7.7) d] were significantly prolonged ( P < 0.01), while no obvious difference was observed between group C and E( P > 0.05), but there was statistically significant difference in MST between group D [(23.7 +/- 2.7) d] and E ( P < 0.05). In addition, clear epithelial structure and infiltration of inflammatory cells were observed in specimens from both groups C and E.

Conclusion: Both donor derived immature DC and third-party DC loaded with donor's antigens can partly induce donor specific transplantation tolerance.