应用抑制性消减杂交技术从斑秃脱发区毛乳头中克隆出一条自身抗原基因

目的　寻找斑秃脱发区毛乳头中特异表达的基因片段 ,探讨斑秃发病机制。方法　应用抑制性消减杂交构建斑秃脱发区毛乳头差异表达基因的cDNA文库 ,并通过PCR筛选、杂交验证和同源性检索对差异表达基因进行分析。结果　成功建立了高消减效率的斑秃脱发区毛乳头cDNA消减文库 ,并克隆到一条斑秃毛乳头特异表达的基因片段DP3( 3 0 7bp) ,应用cDNA斑点杂交及Northern杂交证实它仅在脱发区毛乳头特异表达 ,同源性检索其为一条甲状腺相关的自身抗原基因。结论　DP3在斑秃脱发区毛乳头的特异表达提示其可能参与斑秃的发病过程 ,它的克隆为斑秃发病机制的自身免疫学说进一步提供了实验依据

Cloning of an autoantigen from dermal papillae of lesional alopecia areata follicles by suppression subtractive hybridization

Objective To screen and clone differentially expressed genes in dermal papillae (DP) of lesional follicles from alopecia areata so as to investigate the pathogenesis of alopecia areata. Methods Dermal papillae of lesional and normal follicles were separated from alopecia areata scalps, respectively. Subtractive cDNA library was constructed by SMART cDNA synthesis and suppression subtractive hybridization. Analysis of the differentially expressed genes in DP of lesional follicles was performed by PCR, cDNA dot blot, and homology research. Results An efficient subtractive library of DP of lesional follicles from alopecia areata was established. A differentially expressed gene, DP3 (307 bp), was successfully cloned. cDNA dot hybridization and Northern hybridization proved the gene was expressed specifically only in DP of lesional follicles, and homology search indicated that this gene was a thyroid related autoantigen gene. Conclusion The differentially expressed DP3 gene in DP of lesional follicles may be involved in the pathogenesis of alopecia areata, which provides further experimental proof for the theory of autoimmunity in alopecia areata.