正常人不同部位皮肤表皮干细胞分布规律的研究

Study on the regular pattern of the distribution of skin epidermal stem cells in the different parts of a healthy human body

目的观察正常人不同部位皮肤表皮干细胞分布的规律,分析用P63、CD29单标记和双标记法鉴定表皮干细胞的可行性。方法取5例正常人头顶部、足背、足底、阴阜(阴毛区)、阴囊等21个部位的全层皮肤组织,采用免疫组织化学生物素-链霉亲和素-辣根过氧化物酶(SP)染色法,用P63、CD29作为一抗进行单、双标记。对染色结果作图像分析并以阳性单位(PU)值表示,观察表皮干细胞在各部位皮肤中的分布情况。结果 P63单标记法及P63、CD29双标记法染色均显示, 正常人体21个部位中,足背皮肤的PU值最小,头皮PU值最大。CD29单标记法染色显示,足底皮肤 PU值[(11．9±1．5)％]最小,头皮PU值[(29．1±5．0)％]最大。毛发区皮肤P63、CD29单、双标记染色的PU值均高于汗毛区(P<0．01),但躯干与四肢部位皮肤P63、CD29单标记及双标记染色的 PU值比较,差异均无统计学意义(P>0．05)。结论正常人头顶部、阴阜、阴囊皮肤组织中的表皮干细胞多于其他部位。P63、CD29单标记法对表皮干细胞的敏感性较高,特异性较低,而P63、CD29 双标记法的敏感性较低,特异性较高;后者不失为鉴定表皮干细胞较为简便、有效的方法。

Objective To investigate the regular pattern of the distribution of skin epidermal stem cells （ESCs） in the different parts of a healthy human body, and to evaluate the feasibility of the identification of ESCs by P63 and CD29 with single and double labeling. Methods Full-thickness skin samples from 21 parts （including scalp, dorsum of foot, sole of foot, pubic region, and scrotum） of 5 healthy persons were harvested for the study. Immunohistochemistry method with biotin-streptavidin-horseradish peroxidase （SP） was employed with P63 and CD29 as the first antibody to carry out single and double labeling. The staining results were subjected to image analysis. The distribution of the ESCs in the skin from the above parts was observed and expressed as positive unit （PU） value. Results It was found by P63 single labeling and P63 and CD29 double labeling that the PU value in the dorsum of foot was the lowest while that in the scalp was the highest among all the parts of a healthy body. It was also found by CD29 single labeling that the PU value in the dorsum of foot was the lowest[（11.9 ± 1.5）%] while highest in the scalp [ （ 29.1 ± 5.0） % ]. The PU value in the hairy region of a human body was evidently higher than that in the non-hairy region （ P 〈0.01 ） , when examined by P63 and CD29 single and double labeling. But there was no difference in the PU values between the trunk and limbs by means of P63 and CD29 single and double labeling （ P 〉 0.05）. Conclusion There are more ESCs in the skin from the scalp, mons pubis and scrotum than other parts of the body. Single P63 or CD29 labeling exhibits higher sensitivity but lower specificity in the identification of ESCs. While the double labeling method exhibits higher specificity but lower sensitivity. Above all, it seems that the double labeling may be a simple and effective method for the identification of ESCs.