中文摘要：

目的 探讨共刺激分子B7-H3在小鼠角膜中的表达情况以及在角膜移植免疫赦免中的作用.方法 实验研究.以C57BL/6小鼠为供体、BALB/c小鼠为受体建立角膜移植实验模型,采用简单随机抽样方法,取8只未行角膜移植的BALB/c小鼠作为正常对照组,另取8只BALB/c小鼠作为自体角膜移植组,最后30只BALB/c小鼠进行同种异体角膜移植；按Sonoda法观察小鼠角膜移植后的存活率,8周内植片混浊评分≥2分判定为排斥组,8周时未达到2分的认为是存活组；各组各取3只眼球,HE染色后行组织病理学观察并行B7-H3分子的免疫组织化学检测；各组各取5只眼角膜,行荧光定量PCR检测B7-H3分子mRNA的表达情况.各组角膜组织中的B7-H3 mRNA表达差异倍数比较采用设计单因素的方差分析,组间的多重比较采用LSD-t检验.结果 同种异体角膜移植组并未完全排斥,30只小鼠中有9只存活,21只排斥,移植存活率为30％；自体角膜移植组移植存活率为100％；免疫组织化学表明B7-H3分子在正常对照组和自体角膜移植组的角膜上皮、内皮细胞和虹膜睫状体中均有表达,在存活组中的表达明显增加,而在排斥组中的表达明显减少；qPCR检测在正常对照组（4.30±0.023）和自体角膜移植组（4.33±0.031）中均可以检测出B7-H3分子mRNA的表达；同种异体角膜移植排斥组B7-H3分子的mRNA表达程度（3.89±0.037）明显下降；但在同种异体角膜移植存活组中B7-H3分子的mRNA表达（5.04±0.058）明显增加；将各组B7-H3 mRNA的表达差异进行统计学分析,先进行方差齐性检验（F =429.546）,再采用LSD法进行两两比较,除了正常对照组与自体角膜移植组之间差异无统计学意义（P =0.387）之外,正常对照组与存活组及排斥组比较,差异均有统计学意义（P =0.001,0.003）结论 B7-H3分子在促进角膜移植的免疫赦免中发挥一定的作用,可能是维持移植角膜免疫耐受状态的重要

英文摘要：

Objective To investigate the role of B7-H3 in the immune reaction of corneal transplantation in mice Methods Experimental study.Thirty Corneas of C57BL/6 mice 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） ; 8 BALB/c Corneas into their own eyes belonged to isografts（Ⅰ） ;In addition,8 normal 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-H3 mRNA expression.Repeated-measures analysis of variance （factorial analysis） followed by LSD test were used for post hoc analysis for expression differences of B7-H3 mRNA between groups.Results There were 9 accepted grafts and 21 rejected grafts in 30 mice,and transplantation survival rate was 30％ in the allograft group,while all grafts were transparent,and transplantation survival rate was 100％ in the isografts.IHC results showed that B7-H3 was expressed on the corneal epithelium,endothelium and irisciliary body of both normal corneas and Isografts; B7-H3 expression 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-H3 mRNA 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）.Conclusion All above show that B7-H3 may play an important role in the maintenance of ocular immune privilege.