Cloning of a novel MHC-encoded serine peptidase highly expressed by cortical epithelial cells of the thymus
Cloning of a novel MHC-encoded serine peptidase highly expressed by cortical epithelial cells of the thymus
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DOI：
10.1006/cimm.1999.1543
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发表时间：
1999-09-15
影响因子：
4.3
通讯作者：
Gruen, JR
中科院分区：
文献类型：
--
作者：
Bowlus, CL;Ahn, J;Gruen, JR
皮质胸腺上皮细胞（cTEC）在T细胞的阳性选择过程中的抗原呈递已被证明不同于其他抗原呈递细胞。在MHC II类呈递的情况下，与组织蛋白酶S相反，组织蛋白酶L至少部分地负责不变链的降解。然而，必须涉及其他蛋白酶。我已经鉴定了一种推定的丝氨酸蛋白酶，其在胸腺中特异性表达。编码在I类主要组织相容性复合体（MHC）区域内，该基因与溶酶体脯氨酰羧肽酶具有序列同源性，表明它是丝氨酸蛋白酶。因此，我们将该基因命名为胸腺特异性丝氨酸蛋白酶（TSSP）。原位杂交和免疫荧光染色显示，TSSP是专门表达的皮质胸腺上皮告诉，最强的染色周围血管和胸腺囊。TSSP的鉴定进一步支持了以下理论：胸腺皮质中的MHC II类抗原加工和呈递涉及不同于其他抗原呈递细胞的蛋白水解环境。(C)北京：科学出版社.
Antigen presentation by cortical thymic epithelial cells (cTEC) during the positive selection of T cells has been shown to differ from that of other antigen-presenting cells. In the case of MHC class II presentation, cathepsin L as opposed to cathepsin S is responsible at least in part for the degradation of invariant chain. Other proteases, however, must be involved. me have identified a putative serine protease that is specifically expressed in the thymus. Encoded within the class I major histocompatibility complex (MHC) region, this gene has sequence homology with lysosomal prolylcarboxypeptidase, suggesting that it is a serine protease. We have, therefore, designated this gene thymus-specific serine protease (TSSP). In situ hybridization and immunofluorescence staining reveal that TSSP is expressed exclusively by cortical thymic epithelial tells, with the strongest staining noted around vessels and the thymic capsule. The identification of TSSP further supports the theory that MHC class II antigen processing and presentation in the thymic cortex involves a proteolytic milieu that differs from that of other antigen-presenting cells. (C) 1999 Academic Press.