Ghali Lucy, Wong Soon-Tee, Tidman Nick, Quinn Anthony, Philpott Michael P, Leigh Irene M
Center for Cutaneous Research, Barts, and the London, Queen Mary's School of Medicine and Dentistry, London, UK.
J Invest Dermatol. 2004 Feb;122(2):433-42. doi: 10.1046/j.0022-202X.2004.22207.x.
Basal keratinocytes in the epidermis and hair follicle are biologically heterogeneous but must include a stable subpopulation of epidermal stem cells. In animal models these can be identified by their retention of radioactive label due to their slow cycle (label-retaining cells) but human studies largely depend on in vitro characterization of colony forming efficiency and clonogenicity. Differential integrin expression has been used to detect cells of increased proliferative potential but further stem cell markers are urgently required for in vivo and in vitro characterization. Using LHM2, a monoclonal antibody reacting with a high molecular weight melanoma-associated proteoglycan core protein, a subset of basal keratinocytes in both the interfollicular epidermis and the hair follicle has been identified. Coexpression of melanoma-associated chondroitin sulfate proteoglycan with keratins 15 and 19 as well as beta 1 and alpha 6 integrins has been examined in adult and fetal human skin from hair bearing, nonhair bearing, and palmoplantar regions. Although melanoma-associated chondroitin sulfate proteoglycan coexpression with a subset of beta 1 integrin bright basal keratinocytes within the epidermis suggests that melanoma-associated chondroitin sulfate proteoglycan colocalizes with epidermal stem cells, melanoma-associated chondroitin sulfate proteoglycan expression within the hair follicle was more complex and multiple subpopulations of basal outer root sheath keratinocytes are described. These data suggest that epithelial compartmentalization of the outer root sheath is more complex than interfollicular epidermis and further supports the hypothesis that more than one hair follicle stem cell compartment may exist.
表皮和毛囊中的基底角质形成细胞在生物学上具有异质性，但必须包含一个稳定的表皮干细胞亚群。在动物模型中，这些细胞可因其周期缓慢而保留放射性标记（标记保留细胞）从而得以识别，但人体研究很大程度上依赖于对集落形成效率和克隆形成能力的体外特性分析。不同整合素的表达已被用于检测增殖潜能增强的细胞，但体内和体外特性分析迫切需要更多的干细胞标志物。利用LHM2（一种与高分子量黑素瘤相关蛋白聚糖核心蛋白反应的单克隆抗体），已在毛囊间表皮和毛囊中鉴定出了基底角质形成细胞的一个亚群。在来自有毛、无毛和掌跖区域的成人及胎儿皮肤中，已检测了黑素瘤相关硫酸软骨素蛋白聚糖与角蛋白15和19以及β1和α6整合素的共表达情况。尽管黑素瘤相关硫酸软骨素蛋白聚糖与表皮内β1整合素明亮的基底角质形成细胞亚群共表达表明黑素瘤相关硫酸软骨素蛋白聚糖与表皮干细胞共定位，但毛囊内黑素瘤相关硫酸软骨素蛋白聚糖的表达更为复杂，且描述了基底外根鞘角质形成细胞的多个亚群。这些数据表明，外根鞘的上皮分区比毛囊间表皮更为复杂，并进一步支持了可能存在不止一个毛囊干细胞区室的假说。
