Effects of Foxp3 gene modified dendritic cells on mouse corneal allograft rejection.

OBJECTIVE To investigate the effect of Foxp3 gene modified dendritic cells (Foxp3 + DC) on allogeneic T cells proliferation and to study the effect of Foxp3 + DC on corneal allograft rejection. METHODS Lentivirus-Foxp3 was transfected into DC2.4 cells, as Foxp3 + DC cells. 42 BALB/c mice were randomly divided into: Group A (n = 6), normal group; Group B (n = 12), Group C (n = 12) and Group D (n = 12), allograft groups, were treated with normal saline, DC2.4, Foxp3 + DC by intraperitoneal injection, respectively. RESULTS Compared with the control group, Foxp3 protein in the Foxp3 + DC cells increased significantly (P < 0.05); the expressions of CD80 and CD86 immunophenotypes of Foxp3 + DC cells decreased significantly (P < 0.05); IL-12 secretion reduced (P < 0.05), but IL-10 secretion was promoted (P < 0.05). The average transplant survival time in Group B was (14.833 ± 1.472) d, and Group C and Group D led to a statistically significant prolongation of transplant survival to (17.667 ± 1.366, 23.000 ± 2.000) d (P < 0.05) respectively. 14 d after transplantation, as compared with Group C and D, the expressions of IFN-γ in grafts markedly increased in Group B. 14 d after transplantation, as compared with Group B, the expressions of Foxp3 mRNA, IDO mRNA in grafts decreased remarkably in Group C and D (P < 0.05); as compared with Group C, the expressions of Foxp3 mRNA, IDO mRNA in grafts decreased remarkably in Group D (P < 0.05). CONCLUSION Foxp3 + DC cells reduce the expression of costimulatory factors, reduce the secretion of IL-12, promote IL-10 production and inhibit the stimulation of alloreactive T cell proliferation response capacity. Foxp3 + DC cells play important roles in inhibiting corneal allograft immune response and prolonging graft survival time.