Tissue regeneration - identification and characterization of new cell surface marker for skin stem cells

Stat 3在角质形成干细胞迁移的信号转导中起着至关重要的作用。为了阐明Stat 3在信号传导迁移中的作用，我们研究了Stat 3缺陷角质形成细胞中通过整合素受体的细胞内信号传导途径。Stat 3缺陷的角质形成细胞表现出增加的粘附性和在胶原基质上的快速铺展。Stat 3缺陷型角质形成细胞酪氨酰过度磷酸化的局灶性粘连数量增加。免疫沉淀分析显示，p130 Cas是组成性过度磷酸化的酪氨酸残基，而其他粘着斑分子，如FAK和桩蛋白没有。这些结果有力地表明，角质形成细胞中的Stat 3在p130 Cas酪氨酸磷酸化的转换中起关键作用，调节细胞向基质的迁移，导致生长因子依赖的细胞迁移。 ...更多信息 富含Ne的重复序列和免疫球蛋白样结构域在小鼠中通过基因靶向被破坏。出生后，LIG-1缺陷小鼠的尾巴和面部区域出现皮肤变化。受影响的皮肤在组织学上使人联想到人类常见皮肤病“银屑病”中的表皮。LIG-1 mRNA在毛囊隆突区的强表达可能提示LIG-1在角质形成干细胞中的强表达。有趣的是，LIG-1的表达明显下调银屑病皮损，表明LIG-1参与表皮角质形成细胞的生长调节。手掌和脚底不同于其他身体部位的临床和组织学外观，对机械应力的反应，角蛋白9的分布。因为角蛋白9仅在掌跖基底上角化细胞层中表达，所以它被认为是手掌和脚底的分化标志物。我们研究了掌跖间充质对非掌跖表皮角蛋白9诱导的影响。虽然nonpalmoplantar角质形成细胞不表达角蛋白9的mRNA与nonpalmoplantar成纤维细胞培养时，他们表达它与掌跖成纤维细胞来源于乳头状真皮共培养。纯表皮片从nonpalmoplantar皮肤移植到人类唯一的伤口表现出转分化掌跖表型和角蛋白9表达。少

Stat3 plays a crucial role in transducing a signal for migration of keratinocyte stem cells. To clarify the role of Stat3 in signaling the migration, we studied the intracellular signaling pathway through an integrin receptor in Stat3-deficient keratinocytes. Stat3-deficient keratinocytes demonstrated increased adhesiveness and fast spreading on a collagen matrix. Stat3-deficient keratinocytes had an increased number of tyrosyl-hyperphosphorylated focal adhesions. Analyses with immunoprecipitation revealed that p130Cas was constitutively hyperphosphorylated on tyrosine residues, while other focal adhesion molecules such as FAK and paxillin were not. These results strongly suggest that Stat3 in keratinocytes plays a critical role in turnover of tyrosine phosphorylation of p130Cas, modulating cell adhesiveness to the substratum leading to growth factor-dependent cell migration.The gene encoding a transmembrane glycoprotein LIG-1, of which extracellular region was organized with the leuci … More ne-rich repeats and immunoglobulin-like domains, was disrupted in mice by gene targeting. LIG-1-deficient mice developed a skin change on the tail and facial area after birth. The affected skin was histologically reminiscent of the epidermis in human common skin disease "psoriasis". The strong expression of LIG-1 mRNA in the bulge area of the hair follicles may suggest the strong expression of LIG-1 in the keratinocyte stem cells. Interestingly, the LIG-1 expression was apparently down-regulated in the psoriatic lesions, suggesting that LIG-1 is involved in the growth regulation of epidermal keratinocytes.Palms and soles differ from other body sites in terms of clinical and histologic appearance, response to mechanical stress, and the distribution of keratin 9. Because keratin 9 is exclusively expressed In the palmoplantar suprabasal keratinocyte layers, it is considered a differentiation marker of palms and soles. We studied palmoplantar mesenchymal influences on keratin 9 induction in nonpalmoplantar epidermis. Although nonpalmoplantar keratinocytes did not express keratin 9 mRNA when cultured with nonpalmoplantar fibroblasts, they did express it in cocultures with palmoplantar fibroblasts derived from papillary dermis. Pure epidermal sheets from nonpalmoplantar skin grafted on the human sole wounds showed transdifferentiation to palmoplantar phenotype and expressed keratin 9. Less