Aisenberg J, Ebert E C, Mayer L
Division of Gastroenterology, Mount Sinai Medical Center, New York, New York.
Gastroenterology. 1993 Nov;105(5):1421-30. doi: 10.1016/0016-5085(93)90147-5.
Superantigens are a class of potent T-cell mitogens that activate T cells using specific antigen receptor V regions. Superantigens have been implicated in the pathogenesis of several autoimmune diseases, including inflammatory bowel disease. The present study examines the role of superantigens in the human gastrointestinal immune response.
Human intestinal epithelial cells and T lymphocytes were obtained from surgical specimens and cultured in the presence or absence of exogenous superantigens. Activation of T cells and V region usage were measured by thymidine incorporation and by cell staining using a panel of monoclonal antibodies.
Neither epithelial cells from normal nor diseased intestinal mucosa expressed virally encoded, endogenous superantigens. However, 50% of epithelial cell preparations could present exogenous bacterial superantigens to T cells. In the other 50%, a defect in this function was observed, which did not represent production of suppressive factors or absence of accessory cytokines. Mucosal T lymphocytes proliferated in response to superantigens in vitro, expressing increased transferrin receptor, interleukin-2 receptor, and HLA-DR.
A superantigen-driven mucosal immune response may occur in health and in chronic inflammatory states. The intestinal epithelial cell may mediate this response, through presentation of superantigens to mucosal T lymphocytes.
超抗原是一类强效的T细胞丝裂原，可利用特定的抗原受体V区激活T细胞。超抗原已被认为与包括炎症性肠病在内的几种自身免疫性疾病的发病机制有关。本研究探讨超抗原在人类胃肠道免疫反应中的作用。
从手术标本中获取人肠上皮细胞和T淋巴细胞，并在有或无外源性超抗原的情况下进行培养。通过胸腺嘧啶核苷掺入法以及使用一组单克隆抗体进行细胞染色来检测T细胞的激活和V区使用情况。
正常和患病肠黏膜的上皮细胞均未表达病毒编码的内源性超抗原。然而，50%的上皮细胞制剂能够将外源性细菌超抗原呈递给T细胞。在另外50%的制剂中，观察到该功能存在缺陷，这并非抑制因子的产生或辅助细胞因子的缺乏所致。黏膜T淋巴细胞在体外对超抗原产生增殖反应，表达增加的转铁蛋白受体、白细胞介素-2受体和HLA-DR。
超抗原驱动的黏膜免疫反应可能在健康状态和慢性炎症状态下发生。肠上皮细胞可能通过将超抗原呈递给黏膜T淋巴细胞来介导这种反应。
