Effect of IL-12 and Th1/Th2 in corneal transplantation immune tolerance induced by IL-10 modified dendritic cells in rat

Objective To study the effect of interleukin-12(IL-12) and Th1/Th2 in corneal transplantation immune tolerance induced by IL-10 modified dendritic cells(DC) in rat.Methods Male receptor SD rats were divided into control group(injected PBS 0.1 mL via tail vein at 3 days before operation),6-DC group(injected 2×106 6-DC 0.1 mL via tail vein at 3 days before operation),IL-10-DC group(injected 2×106 IL-10-DC 0.1 mL via tail vein at 3 days before operation),14 cases in each group.Female Wistar rats were set as donators to establish the penetrating corneal transplantation model.The postoperative corneal grafts were clinically observed and the survival time was recorded.The expressions of IL-12,IL-2,IFN-γ,IL-4,IL-10 mRNA at postoperative 14 days were detected by RT-PCR.Results Graft survival time in control group,6-DC group and IL-10-DC group were(10.63±2.00)days,(18.88±1.36)days and(24.50±2.07)days.Compared with control group,the survival time in 6-DC group and IL-10-DC group were obviously prolonged,there were significant differences(both P0.01),and the IL-10-DC group was obviously longer than 6-DC group,there was significant difference(P0.01).At postoperative 14 days,in control group the expression level of IL-12 mRNA(0.80±0.00),IL-2 mRNA(1.03±0.06),IFN-γ mRNA(0.97±0.03) were the highest,IL-4 mRNA(0.13±0.00) and IL-10 mRNA(0.34±0.02) were the lowest;In IL-10-DC group,the expression of IL-12 mRNA(0.39±0.01),IL-2 mRNA(0.61±0.01) and IFN-γ mRNA(0.43±0.02) were the lowest,IL-4 mRNA(0.19±0.00) and IL-10 mRNA(0.88±0.01) were the highest,there was statistical difference among three groups.Conclusion IL-10 modified DC can induce the corneal transplantation immune tolerance of rat,IL-12 and Th1/Th2 play the key role in corneal transplantation immune,the low expression of IL-12 mRNA and Th1/Th2 deviation is one of the mechanisms of transplantation immune tolerance induced by IL-10 modified DC.