Staphylococcal enterotoxin (specifically A and B) (SE (SEA/SEB))

Staphylococcal enterotoxins, including Enterotoxin A (SEA) and Enterotoxin B (SEB), are potent exotoxins produced by Staphylococcus aureus that function as superantigens. These proteins are highly stable and resistant to heat and proteolysis, allowing them to cause food poisoning upon ingestion. Their primary mechanism involves cross-linking Major Histocompatibility Complex (MHC) class II molecules on antigen-presenting cells with the Vβ region of T-cell receptors (TCR), bypassing the need for specific antigen recognition. This results in the polyclonal activation of a large fraction of T cells and a massive release of pro-inflammatory cytokines, leading to systemic inflammation and toxic shock syndrome. In therapeutic contexts, these toxins are targets for neutralizing antibodies and vaccines, while modified analogs are engineered for use in cancer immunotherapy to induce superantigen-dependent cellular cytotoxicity against tumor-associated antigens.

Other names

Staphylococcal enterotoxin B/SEA analogStaphylococcal superantigenEnterotoxin type AEnterotoxin type BSEASEB

Polyclonal T-cell activation via MHC II and TCR Vβ region cross-linking; Neutralization of toxin-mediated immune activation