角膜缘碱烧伤后应激调控基因的筛选

目的获得新西兰大白兔角膜缘碱烧伤前后参与修复调控的差异表达基因。方法主要采用细胞培养、体外碱烧伤模型的构建、免疫细胞化学、抑制消减杂交和生物信息学等方法。结果初步认定样品之一与编码人类血小板反应蛋白2(TSP2)的基因tsp2高度同源，其中前698bp序列与人类tsp2基因完全一样，后230bp与一种人类Trp-4相关蛋白样的新蛋白(人类染色体定位为20q11．21—12)相似，后者属于调控蛋白类，具典型的CpG岛特征。目前已在Gen—Bank中登录(AF454919)。结论该样品可能是TSP家族中TSP2系列的新成员，它对细胞去黏合状态的诱导和抑制血管发生功能的协调可能是促进角膜碱烧伤后创伤愈合的重要原因。

Screening of stress-mediated genes after limbal corneal alkali burn

Objective To acquire stress-mediated genes involving repair regulation before and after corneal limbus alkali burn in New Zealand white rabbits. Methods The main screening techniques included suppression subtractive hybridization (SSH), RT-PCR, molecular clone, dot blot and bio-informatics. Results The screening results showed that one of expressed sequence tags (ESTs) initially had high homology with TSP2 coding thrombspondin-2. The anterior 698bp was totally the same with tsp2 and the posterior 230bp was similar with another new homosapiens protein belonged to control protein with typical CpG island and associated with Trp-4 that was located in 20q11.21-12. At present, the EST was registered in the GenBank (AF454919). The result of RT-PCR using primer designed from above EST showed that there existed significant difference in the expression of TSP2 between limbal cornea and central cornea after alkali burn, which could be explained with the theory of corneal stem cells in wound healing. Conclusions The corresponding protein about this gene fragment seems like a new member of the tsp2 of tsp family. In the meantime, it can induce de-adhesion of cells state and inhibit angiogenesis in the course of trauma, which is probably one of important reasons for promotion of corneal wound healing after alkali burn.