Acha-Orbea H
Ludwig Institute for Cancer Research, Lausanne Branch, Epalinges, Switzerland.
Ann Rheum Dis. 1993 Mar;52 Suppl 1(Suppl 1):S6-16. doi: 10.1136/ard.52.suppl_1.s6.
Superantigens are bacterial, viral, or retroviral proteins which can activate specifically a large proportion of T cells. In contrast with classical peptide antigen recognition, superantigens do not require processing to small peptides but act as complete or partially processed proteins. They can bind to major histocompatibility complex class II molecules and stimulate T cells expressing particular T cell receptor V beta chains. The other polymorphic parts of the T cell receptor, which are crucial for classical antigen recognition, are not important for this interaction. When this strategy is used a large proportion of the host immune system can be activated shortly after infection. The activated cells have a wide variety of antigen specificities. The ability to stimulate polyclonal B (IgG) as well as T cell responses raises possibilities of a role for superantigens in the induction of autoimmune diseases. Superantigens have been a great tool in the hands of immunologists in unravelling some of the basic mechanisms of tolerance and immunity.
超抗原是细菌、病毒或逆转录病毒蛋白，能够特异性激活很大比例的T细胞。与经典的肽抗原识别不同，超抗原无需加工成小肽，而是以完整或部分加工的蛋白质形式发挥作用。它们可与主要组织相容性复合体II类分子结合，并刺激表达特定T细胞受体Vβ链的T细胞。对于经典抗原识别至关重要的T细胞受体的其他多态性部分，在这种相互作用中并不重要。当采用这种策略时，感染后不久宿主免疫系统的很大一部分就能被激活。被激活的细胞具有广泛的抗原特异性。刺激多克隆B细胞（IgG）以及T细胞反应的能力增加了超抗原在自身免疫性疾病诱导中发挥作用的可能性。超抗原一直是免疫学家手中揭示耐受性和免疫一些基本机制的有力工具。
