Okochi H, Kato M, Nashiro K, Yoshie O, Miyazono K, Furue M
Department of Dermatology, University of Tokyo, Branch Hospital, Japan.
Br J Dermatol. 1997 Dec;137(6):856-63.
Tetra-spans transmembrane family (TSTF) members (CD9, CD37, CD53, CD63, CD81 and CD82) have potent effects on cell growth, motility and adhesion in various cells. However, little is known about their expression in human skin. Using immunohistological techniques, we have studied the localization of all six members of TSTF in normal and carcinomatous human keratinocytes. CD9, CD81 and CD82 were expressed in the entire living layers of the epidermis. Their staining pattern was quite similar, and was mainly intercellular with occasional intracellular immunoreactivity. CD53 expression was confined to the intercellular spaces of the upper spinous or granular layer in the normal epidermis. No clear-cut expression of CD63 could be detected in the epidermis. CD37 was not detected at all. Cultured human keratinocytes also expressed CD9, CD81 and CD82 at the surface membrane of cell-cell boundaries. Expression of CD37 and CD53 was negative in cultured keratinocytes, while CD63 was clearly localized in the cytoplasmic lysosomes. An immunoprecipitation assay revealed that alpha 3 beta 1 integrin is molecularly associated with CD9. The expression of CD9, CD81 and CD82 was markedly down-regulated in basal cell carcinoma but not in Bowen's disease. The abundant and differential expression of TSTF molecules and the selective association of CD9 with alpha 3 beta 1 integrin suggest that the TSTF molecules may be involved in the regulation of epidermal differentiation and integrity in vivo.
四跨膜蛋白家族（TSTF）成员（CD9、CD37、CD53、CD63、CD81和CD82）对多种细胞的生长、运动和黏附具有显著影响。然而，它们在人类皮肤中的表达情况却鲜为人知。我们运用免疫组织学技术，研究了TSTF的所有六个成员在正常和癌性人角质形成细胞中的定位。CD9、CD81和CD82在表皮的整个活细胞层中表达。它们的染色模式非常相似，主要为细胞间染色，偶尔有细胞内免疫反应。CD53的表达局限于正常表皮棘层上部或颗粒层的细胞间隙。在表皮中未检测到CD63的明确表达。完全未检测到CD37。培养的人角质形成细胞在细胞 - 细胞边界的表面膜上也表达CD9、CD81和CD82。培养的角质形成细胞中CD37和CD53的表达为阴性，而CD63明显定位于细胞质溶酶体中。免疫沉淀试验表明，α3β1整合素在分子水平上与CD9相关联。CD9、CD81和CD82的表达在基底细胞癌中显著下调，但在鲍温病中未下调。TSTF分子的丰富且差异表达以及CD9与α3β1整合素的选择性关联表明，TSTF分子可能参与体内表皮分化和完整性的调节。
