The murine homolog of human Ep-CAM, a homotypic adhesion molecule, is expressed by thymocytes and thymic epithelial cells
The murine homolog of human Ep-CAM, a homotypic adhesion molecule, is expressed by thymocytes and thymic epithelial cells
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DOI：
10.1002/eji.1830260220
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发表时间：
1996-02-01
影响因子：
5.4
通讯作者：
Farr, AG
中科院分区：
文献类型：
--
作者：
Nelson, AJ;Dunn, RJ;Farr, AG
在本报告中，我们证明了gp 40。一种先前显示在体外由胸腺上皮细胞系和在体内由胸腺上皮细胞表达的分子是人Ep-CAM的鼠同系物，一种钙非依赖性同型粘附分子。胸腺细胞和外周T细胞也以低水平表达gp 40。在成年胸腺中。gp 40表达与胸腺细胞成熟状态呈负相关。与CD 4（-）CD 8（-）和CD 4（+）CD 8（+）胸腺细胞群相关的水平最高。超微结构免疫组化显示，gp 40定位于胸腺细胞/上皮细胞接触的区域，并表明gp 40也表达胸腺树突状细胞。在胎儿发育过程中。妊娠14-16天的胸腺细胞表达高水平的gp 40。在后期阶段。所观察到的gp 40（-）细胞频率和表达水平的下降与妊娠第18天出现的α β（+）胸腺细胞相关。在短期文化中。用伴刀豆球蛋白A刺激未分级的成体胸腺细胞增加gp 40表达，特别是在CD 3（ht）和CD 3（int）胸腺细胞群体中。这表明Ep-CAM.最初认为主要表达于上皮细胞。也由胸腺细胞表达。T细胞和抗原呈递细胞。错误的可能性，Ep-CAM可能有助于胸腺细胞和上皮细胞或树突状细胞之间的粘附相互作用，无论是在胸腺细胞发育或外周T细胞运输和功能的背景下。
In this report, we demonstrate that gp40. a molecule previously shown to be expressed by thymic epithelial cell lines in vitro and by thymic epithelial cells in vivo, is the murine homolog of human Ep-CAM, a calcium-independent homotypic adhesion molecule. gp40 Is also expressed at low levels by thymocytes and peripheral T cells. in the adult thymus. gp40 expression was inversely related to the state of thymocyte maturation. with the highest levels associated with CD4(-) CD8(-) and CD4(+)CD8(+) thymocyte populations. Ultrastructural immunohistochemistry revealed gp40 localization to areas of thymocyte/epithelial contact and demonstrated that gp40 is also expressed thymic dendritic cells. During fetal development. thymocytes at days 14-16 of gestation expressed high levels of gp40. At later stages. the observed decline in the frequency of gp40(-) cells and levels of expression correlated with the emergence of alpha beta(+) thymocytes by day 18 of gestation. In short-term cultures. stimulation of unfractionated adult thymocytes with concanavalin A increased gp40 expression, particularly among CD3(ht) and CD3(int) thymocyte populations. This demonstration that Ep-CAM. initially considered to be expressed primarily epithelial cells. is also expressed by thymocytes. T cells and antigen-presenting cells. mises the possibility that Ep-CAM may contribute to adhesive interactions between thymocytes and epithelial cells or dendritic cells, either in the context of thymocyte development or peripheral T cell trafficking and function.