Islam Md Saiful, Zhou Huanmin
College of Animal Science and Medicine, Inner Mongolia Agricultural University, Huhhot 010018, Inner Mongolia, People's Republic of China.
Eur J Dermatol. 2007 Jul-Aug;17(4):302-8. doi: 10.1684/ejd.2007.0204. Epub 2007 Jun 1.
This study was undertaken to select putative epidermal stem cells from cultured keratinocytes in Cashmere goat fetus and to characterize them in stem cell nature. The keratinocytes were separated enzymatically from fetuses of 12-16 weeks of gestation and co-cultured with mitotically inactivated fetal skin fibroblasts. Putative epidermal stem cells were selected by rapid adherence on collagen type IV substrate and maintained in three different medium conditions: high Ca(2+) concentration, low Ca(2+) concentration, and low Ca(2+) concentration with 50% conditioned medium. The results indicated that epidermal basal cells grew clonally on the feeder layer and were maintained for approximately 48 population doublings without showing signs of replicative senescence. Clonal analysis revealed the presence of three clonal types: holoclones, meroclones and paraclones. Selected keratinocytes on collagen IV substrate could be propagated serially in three medium conditions and the population showed high colony formation efficiency, the same morphology with a high nuclear to cytoplasmic ratio and positive expression of p63, Keratin 19, Keratin 15 and CD71, which are believed to be possible specific markers for keratinocyte stem cells. This study reports a method to isolate a selected keratinocyte population with the characteristics of stem cells.
本研究旨在从绒山羊胎儿培养的角质形成细胞中筛选假定的表皮干细胞，并对其干细胞特性进行表征。通过酶解法从妊娠12 - 16周的胎儿中分离角质形成细胞，并与有丝分裂失活的胎儿皮肤成纤维细胞共培养。通过在IV型胶原底物上快速贴壁筛选假定的表皮干细胞，并在三种不同的培养基条件下进行培养：高钙（2+）浓度、低钙（2+）浓度以及含50%条件培养基的低钙（2+）浓度。结果表明，表皮基底细胞在饲养层上克隆生长，并维持约48次群体倍增，未显示出复制性衰老的迹象。克隆分析揭示存在三种克隆类型：全克隆、部分克隆和旁克隆。在IV型胶原底物上筛选的角质形成细胞可在三种培养基条件下连续传代，群体表现出高集落形成效率，具有相同的形态，核质比高，且p63、角蛋白19、角蛋白15和CD71呈阳性表达，这些被认为可能是角质形成细胞干细胞的特异性标志物。本研究报道了一种分离具有干细胞特性的选定角质形成细胞群体的方法。
