摘要
细胞表面糖在细胞分化及细胞周期中均有一定的变化,而且还与细胞间的识别与信息传递有关,为了解膜表面糖复合物在细胞凋亡过程中的作用,通过地塞米松诱导小鼠胸腺细胞凋亡为模型,利用对8种抗原结构相关的寡糖特异的单克隆抗体,观察凋亡过程中胸腺细胞表面岩藻糖化糖抗原结构的变化。免疫组化的分析结果表明:正常胸腺细胞表面的糖抗原主要是含有岩藻糖基的H-2和Le ̄b.而凋亡的胸腺细胞表面出现GlcNAcβ1-3Gal-,Galβ1-4GlcNAcβ1-3Gal-及双岩藻糖化抗原Le ̄Y,同时Le ̄b消失。磷脂提取结果表明在给药3h后膜的PS条带明显增加,通过对诱发细胞凋亡过程中组化分析的时相变化观察发现:凋亡细胞膜表面糖抗原的变化在给药1h(即凋亡发生前)就出现。以上结果说明凋亡过程中胸腺细胞表面岩藻糖化抗原发生了变化,且此变化可能与细胞凋亡的始发有关。
The thymus cells from C-57 mouse were used as a model system to investigate the change of carbohydrate chains on the cells surface during apoptosis induced by dexamethasone.The results of indirect immunohistochemistry showed that: 1 ) The fucosylated antigens H-2 and Le ̄b were detected on the surface of normal thymocyte. 2) The carbohydrates GlcNAcβ 1-3Gal-,Galβ 1-4GlcNAcβ 1-3Gal, and fucosylated antigen Le ̄y were detected on the surface of apoptotic thymocyte. 3) The changes of time course of the carbohydrate on the surface of thymocyte was diffrent from that of phosphatidyl serine,and the change of carbohydrate antigens appeared before the morphological appearance during apoptosis.The results indicated that the fucosylation of carbohydrates chain on the cell surface changed during apoptosis and this change may be related to the initiation of apoptosis.