| BackgroundThe immunological rejection of corneal transplantation is a T-cell mediated delayed hypersensitivity and a complete process with practice and regulation of many immunology cells and molecules. The activation of T-cell needs the participation of two signals, the MHC antigen peptide signal and the co-stimulatory signal. If lack of the co-stimulatory signal supplied by the co-stimulator, T-cell can not be activated and continues to stay in an inability statement.The immune reaction after keratoplasty is a considerably complex process which is made of different kinds of immune cells and cytokines. Positive costimulatory molecules can promote T cell activation, proliferation and cytokine generation and lead to graft failure; Negative costimulatory molecules can inhibit T cell activation, proliferation and cytokine generation and promote graft survival. In different phase of T-cell activation, many co-stimulators educe important regulation effect. Among these, B7and TIM family are Important co-stimulators found out recently.Co-stimulate passageway educes important effect in multiple organ transplantation immunological reaction, immunological rejection can be effectively regulated by this passageway and we can explore useful strategy and mean to prevent the immunological rejection activation from this. Homogeneity corneal transplantation is the most effective method to treat cornea blind in nowadays. But the immunological rejection after operation is still the main cause of the operation failure. To elevate the survival rate of cornea transplantation is an problem which need to be urgently solved in clinical practice. Therefore, it is very important and meaningful to continue to research the acute immunology rejection mechanism of cornea transplantation and positively explore satisfactory anti-rejection method from many routes.Part I The role and mechanism of costimulatory molecule B7-H3in the immune reaction of corneal transplantation in miceObjectiveTo investigate the role of B7-H3in the immune reaction of corneal transplantation in miceMethodsExperimental study. Thirty Corneas of C57BL/6mice were orthotopically transplanted into the eyes of BALB/c mice, and graft survival was assessed on the basis of Sonoda’s standard. When the RI grade was≥2, rejection was acknowledged and brought into the rejected group(R),and the others into the accepted group(A);8BALB/c Corneas into their own eyes belonged to isografts (I); In addition,8normal BALB/c mice were the control group(C). At last, three eyes in each group(C, I, A, R groups) were used for HE staining and IHC of B7-H3, and there were five eyes in each group for qPCR to detect B7-H3mRNA expression. Repeated-measures analysis of variance (factorial analysis) followed by LSD test were used for post hoc analysis for expression differences of B7-H3mRNA between groups ResultsThere were9accepted grafts and21rejected grafts in30mice, and transplantation survival rate was30%in the allograft group, while all grafts were transparent, and transplantation survival rate was100%in the isografts. IHC results showed that B7-H3was expressed on the corneal epithelium, endothelium and iris-ciliary body of both normal corneas and Isografts; B7-H3expression increased in the accepted group and decreased in the rejected group. The results of qPCR conformed to the IHC; Repeated-measures analysis of variance (factorial analysis) followed by LSD test were used for post hoc analysis for differences between groups (F=429.546). there was a low B7-H3mRNA expression in the R group (3.89±0.037) and high expression in the A group (5.04±0.058); and C (4.30±0.023),I (4.33±0.031) groups had no significant difference (P=0.387);But there was a significant difference between group R and C(P=0.003)or group A and C(P=0.001).ConclusionAll above show that B7-H3may play an important role in the maintenance of ocular immune privilege.(Chin J Ophthalmol,2013,49:) Part Ⅱ The role of costimulatory molecule Tim-1in the immune reaction of corneal transplantation in ratsObjectiveTo investigate the role of Tim-1in the immune reaction of corneal transplantation in ratsMethods16Corneas of SD rats were orthotopically transplanted into the eyes of Wistar rats, and graft survival was assessed on the basis of Larkin’s standard. When the RI grade was≥5, rejection was acknowledged and brought into the rejected group(R);16Wistar Corneas into their own eyes belonged to isografts(Ⅰ); In addition,8normal BALB/c mice were the control group(C). At last,three eyes in each group(C、I、 Agroups) were used for HE staining and IHC of Tim-1, and there were five eyes in each group for qPCR to detect Tim-1mRNA expression on the day7、14after operation.Resultsthere were8rejected grafts in8rats, and transplantation rejection rate was100%in the allograft group,while all grafts were transparent, and transplantation survival rate was100%in the isografts. IHC results showed that Tim-1was expressed on the corneal epithelium, endothelium and of both normal corneas; Tim-1expression increaseed in both the group A and group I on the day7after operation. Tim-1expression decreased in the group I, but appear to be high in the group A on the day14after operation. The results of qPCR conformed to the IHC.ConclusionAll above show that Tim-1may play an important role not only in the of inflammatary response but aslo in the rejection reaction of the corneal transpantation. |
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