Toxic shock syndrome toxin 1 (None)

Toxic shock syndrome toxin-1 (TSST-1) is a bacterial exotoxin and superantigen produced by certain strains of *Staphylococcus aureus*. It has a molecular weight of approximately 22 kDa and is responsible for the majority of menstrual toxic shock syndrome (TSS) cases, as well as about half of non-menstrual TSS cases. TSST-1 acts by stimulating massive immune activation, leading to the release of large amounts of cytokines. As a superantigen, TSST-1 binds directly to MHC-II molecules and T-cell receptors, causing polyclonal T-cell activation and a cytokine storm, which leads to systemic inflammation and shock.

Other names

TSST-1Staphylococcal enterotoxin FSEF

Superantigen-mediated crosslinking of MHC class II and T-cell receptors, leading to massive T cell activation and cytokine storm.