【摘要】 目的 研究细胞凋亡信号分子Fas和细胞凋亡因子FasL在新鲜及深低温保存后角膜的表达情况、角膜细胞凋亡情况及其与角膜移植免疫排斥反应的关系。方法 (1)对35例角膜移植手术(25例新鲜角膜、10例冷冻保存)剩余组织应用免疫组织化学SABC法分别进行Fas和FasL蛋白染色。(2)应用Tunel法对上述标本进行细胞凋亡的研究。(3)观察35例部分穿透性角膜移植免疫排斥反应发生发展情况。结果 (1)角膜细胞Fas蛋白及FasL蛋白均为细胞质和(或)细胞膜着色。角膜上皮细胞、基质细胞及内皮细胞Fas蛋白均呈阳性表达。角膜上皮细胞及内皮细胞FasL蛋白均呈阳性表达，而角膜基质细胞则无FasL蛋白表达。新鲜角膜和冷冻保存后角膜的Fas、FasL蛋白阳性表达量经统计学分析差异无显著性。(2)凋亡的角膜细胞均为细胞核着色。25例新鲜角膜平均每高倍视野可见凋亡细胞(1.788±0.621)个，经冷冻保存后的角膜(10例)每高倍视野可见凋亡细胞平均为(8.164±2.126)个，经统计学处理P<0.05，差异有显著性。(3)角膜移植免疫排斥反应发生与角膜的新鲜程度有关，新鲜角膜部分穿透性角膜移植术后6～12个月的免疫排斥反应发生率为12%(3/25)，深低温保存角膜移植后6～12个月的免疫排斥反应发生率为10%(1/10)，二者差异无显著性(P>0.05)。结论 (1)新鲜和深低温保存后的角膜均可见Fas、FasL蛋白的表达。其中Fas在角膜上皮、基质和内皮细胞均表达，FasL在角膜上皮、内皮细胞表达，而基质细胞不表达。(2)新鲜角膜可见极少量凋亡细胞，角膜经深低温冷冻保存后，凋亡细胞数量显著增加。降温-复温损伤可能与细胞凋亡有关。(3)角膜移植免疫排斥反应发生与角膜的新鲜程度有一定关系，深低温保存后角膜的抗原性可能降低，不易引起免疫排斥反应的发生。

    【关键词】 Fas蛋白；FasL蛋白；凋亡；角膜移植免疫排斥

    The study on correlation between apoptosis and cornea graft rejection

    YANG Chao-zhong,ZHANG Jun,HUA Shan,et al.

    Qingdao Dongfang Eye Institute,Qingdao 2660021,China

    【Abstract】 Objective To investigate the relationship between expression of Fas/FasL and apoptotic cells in normal cornea and deep cryopreservative with cornea graft rejection in human.Methods SABC immunohistochemistry method was applied to study the expression of Fas/FasL in paraffin-embeded sections of 35 cornea.The tunel(TdT mediated biotin dUTP nick-end labeling,TUNEL) technique was used to study whether apoptosis would happy in both normal cornea and deep cryopreservative in human.Results In all positive cells,Fas/FasL were kytoplasm and cell membrane was stained.The positive expression of Fas protein was detected in 35/55 cornea,so was Fasl protein.Fas protein is expressed in corneal epithelial,keratocyte and endothelial cells.FasL ligand protein was detected in corneal epithelial and endothelial,neither was keratocyte cells.The number of apoptotic cells was significantly higher after cryopreservation(8.164±2.126) than noncryopreservation (1.788±0.621) (P<0.05).The rate of cornea graft rejection was 12%(nomal cornea) and 10%(cryopreservative cornea).Conclusion Fas protein and FasL ligand protein expressed in all cornea were not related to cryopreservation.The freeze-thaw trauma was maybe related to cryopreservation-induced cell apoptosis.It may reduce the rate of cornea graft rejection. ......