胎儿皮肤与成人皮肤的形态结构及表皮干细胞分子标志物的比较

摘要

目的：探讨胎儿皮肤与成人皮肤的形态结构及表皮干细胞分子标志物的差异,为后续皮肤功能的研究及皮肤移植提供理论依据。方法取胎儿背部与成人腿部皮肤,标本取材后立即用10%中性甲醛固定,石蜡包埋。所有标本经石蜡切片,HE染色,观察皮肤表皮、真皮和皮肤附属器的形态结构；应用免疫组织化学法检测皮肤组织中表皮干细胞标志物p63、β1整合素和角蛋白19(K19)的表达。结果胎儿皮肤与成人皮肤表皮、真皮和皮肤附属器结构不同,胎儿表皮由2~3层上皮细胞组成,基底层细胞呈立方形,核圆,染色深,未发现颗粒层细胞,真皮乳头状突起不明显；成人全层皮肤明显厚于胎儿皮肤,尤其是成人皮肤的真皮层明显较胎儿真皮发达,成人皮肤真皮乳头状突起明显,成人表皮由6~7层上皮细胞组成,基底层细胞呈立方形或柱形,细胞核染色较深,呈卵圆形,居中,有明显的颗粒层,但细胞轮廓不清晰,胞质内可见蓝色颗粒。经测定胎儿皮肤表达的p63、β1整合素及K19的平均光密度值高于成人( P<0．01)。结论胎儿皮肤和成人皮肤表皮、真皮和皮肤附属器形态结构存在差异,表皮干细胞分子标志物表达也存在差异。%Objective To explore the differences of morphologic structure and markers of epithelial stem cell be-tween fetal and adult skin and to provide experimental basis for further study of the function of the skin and skin transplantion. Methods The skin was obtained from the part of fatal dorsal and adult leg respectively. After draw-ing materials, the specimens were immediately drawn with 10% neutral formalin-fixed, paraffin-embedded. After all the specimens were sliced series, the structure of epidermis, dermis and skin appendages were observed by HE staining. The quantity of p63,β1 integrin, keratin 19 (K19) expression were determined by immunohistochemis-try. Results There were differences in structures of the epidermis, dermis and skin appendages between fetal and adult skin. In the fetal skin, the epidermis was composed of 2 to 3 layers of epithelial cells and the stratum basale cells were cuboidal, and had round and deeply stained nuclei and the stratum granulosum was not found. Dermis papillae was not obvious. Adult full-thickness skin was thicker than that of fetus, especially the dermis in adult was well developed than fetal dermis. In addition, adult skin epidermis and dermis papillae were obvious than that of fetus. Adult epidermis had 6 to 7 layers of epithelial cells, and stratum basale cells were cuboidalor columnar and deeply staining and nuclei were oval. Epidermis of adult skin had obvious granular but the outline of cell was not clear. There were blue granules in cytoplasm. The values of p63, β1 integrin and K19 MOD of fetal skin were higher than that of adult skin(P<0. 01). Conclusion There are differences between adult and fetal skin epider-mis, dermis and skin appendages. Markers of epidermal stem cell also have obvious differences.