人胎视网膜发育过程中Fas、Fas-L、bax和bcl-2蛋白的表达

Protein expression of genes related to apoptosis in retina of human fetus

目的 研究人胎视网膜发育过程中细胞凋亡相关基因 Fas、Fas- L、bax和 bcl- 2的蛋白表达。 方法 收集 12～ 38周 (受精龄 )胎儿视网膜共 5 0例 ,石蜡包埋切片 ,免疫组织化学染色 ,光镜观察。 结果 发育第 16周和第 38周 ,视网膜节细胞层、内、外核层表达 Fas蛋白。第 2 6周 ,Fas- L 阳性染色开始出现于视网膜各层细胞 ,到第 32周 ,免疫阳性反应主要集中在节细胞层 ,第 38周时 ,神经纤维层也为阳性反应。bax免疫阳性反应从第 12周起出现 ,第 16周 ,节细胞层和外核层多数细胞核为阳性。第 2 4周 ,内核层中的细胞为阳性反应 ,但到第 2 6周时 ,仅 Müller细胞内侧终足为 bax免疫阳性染色。第 2 6周以后 ,视网膜内各种成分都为 bax免疫反应阴性。 bcl- 2免疫阳性反应于第 16周时出现在正在分化的神经母细胞层。第 2 4周开始 ,bcl- 2免疫阳性反应集中于节细胞层的神经胶质细胞以及 Müller细胞的内侧终足。 结论 发育中的视网膜的细胞凋亡可能不依赖 Fas/Fas- L途径。

Purpose To study the proteins expression of genes related to apoptosis of retinal cells in development of human fetus. Methods Fifty cases of retinas of human fetus aged from 12 to 38 weeks were collected and paraffin embedded sections were made. Immunohistochemical method was used. Results Fas protein was expressed by cells of ganglion cell layer, inner and outer nuclear later, which were just formed on 16th week. It was not expressed until 38th week, Fas(+) staining appeared in layers of retina. Fas-L(+) staining was detected in cells of layers of retina on 26th week and the positive staining located in ganglion cell layer on 32th week. Neuronal fiber layer was Fas-L positive. Bax positive staining was detected on 8th week. Bax positive nucleus were observed mainly in GCL and ONL on 16th week. It was in INL on 24th week and in Müller cells inner terminates on 26th week. After this time, all cells of retina were bax immune negative staining. Bcl-2(+) staining appeared in differentiating neuroblastic layer on 16th week. Beginning on 24th week, bcl-2 (+) staining was observed in glial cells of GCL and inner terminates of Müller cell. Conclusion Apoptosis of developing retinal cell may be Fas/Fas-L independent and bax may be involved in apoptosis of the cells.