superantigen


superantigen

 [soo″per-an´tĭ-jen] any of a group of powerful antigens occurring in various bacteria and viruses that bind outside of the normal T cell receptor site and are able to react with multiple T cell receptor molecules, thus activating T cells nonspecifically. Included are staphylococcal enterotoxins and toxins causing toxic shock syndrome and exfoliative dermatitis.

su·per·an·ti·gen

(sū'pĕr-an'ti-jen), An antigen that interacts with the T-cell receptor in a domain outside the antigen recognition site. This interaction induces the activation of larger numbers of T cells than are induced by antigens that are presented in the antigen recognition site leading to the release of numerous cytokines. A single superantigen may potentially activate as much as 15% of the lymphocytic repertoire.
See also: antigen.

superantigen

One of a class of molecules that react with a substantial proportion of the whole population of T cells in the body. They include Staphylococcus aureus ENTEROTOXINS. Staphylococcal enterotoxin A (SEA) is a powerful T-cell mitogen and can give rise to the release of large quantities of CYTOKINES and LEUKOTRIENES. This is believed to be one of the bases of the TOXIC SHOCK SYNDROME.