Kinoshita T, Sasaki F
Department of Biology, School of Dental Medicine, Tsurumi University, Yokohama, Japan.
Histochemistry. 1994 Jul;101(6):391-6. doi: 10.1007/BF00269488.
Polyclonal antibodies were raised against Xenopus larva-specific 58 kDa keratin (PAK58) and adult-specific 63 kDa keratin (PAK63), in order to examine the origin of 63 kDa-keratin-producing cells in the tail skin. By immunofluorescent staining of the tail skin, the 58 kDa keratin was recognized in almost all of the larval epidermal cells, although a small number of PAK58-negative cells were detected at stage 64. In contrast, 63 kDa keratin was immunohistochemically recognized at stage 58, but the signal was very weak. The number of epidermal layers in the tail epidermis increased during a period from stage 58 to stage 64. At stage 64, a small number of PAK63-positive cells was clearly identified in the multilayered tail epidermis. Comparative analysis of successive sections showed that PAK63-positive cells are derived from a cell group differing from PAK58-positive cells. Immunohistochemical studies using cultured epidermal cells demonstrated that 58 kDa keratin is localized in the cytoskeletal bundles of skein cells, whereas 63 kDa keratin is produced not by skein cells but by basal cells and their descendants. These results suggest that basal cells are the adult precursor cells within the larval epidermis even in the tail area.
为了研究尾皮肤中产生63 kDa角蛋白的细胞的起源，制备了针对非洲爪蟾幼体特异性58 kDa角蛋白（PAK58）和成年特异性63 kDa角蛋白（PAK63）的多克隆抗体。通过对尾皮肤进行免疫荧光染色，在几乎所有幼体表皮细胞中都检测到了58 kDa角蛋白，尽管在第64阶段检测到少量PAK58阴性细胞。相比之下，在第58阶段通过免疫组织化学方法检测到了63 kDa角蛋白，但信号非常微弱。从第58阶段到第64阶段，尾表皮中的表皮层数增加。在第64阶段，在多层尾表皮中清楚地鉴定出少量PAK63阳性细胞。连续切片的比较分析表明，PAK63阳性细胞来源于与PAK58阳性细胞不同的细胞群。使用培养的表皮细胞进行的免疫组织化学研究表明，58 kDa角蛋白定位于丝状细胞的细胞骨架束中，而63 kDa角蛋白不是由丝状细胞产生的，而是由基底细胞及其后代产生的。这些结果表明，即使在尾部区域，基底细胞也是幼体表皮中的成年前体细胞。
