Staphylococcal enterotoxin C (SEC)

Staphylococcal enterotoxin C (SEC) is a potent exotoxin and superantigen secreted by Staphylococcus aureus. It is a major cause of staphylococcal food poisoning and is implicated in severe systemic conditions such as toxic shock syndrome (TSS) and sepsis. SEC functions by cross-linking major histocompatibility complex (MHC) class II molecules on antigen-presenting cells with the variable region of the T-cell receptor (TCR) beta-chain, leading to the massive, non-specific activation of T-cells. This results in a cytokine storm characterized by the overproduction of pro-inflammatory cytokines like TNF-alpha and IFN-gamma. The production of SEC is tightly controlled by the accessory gene regulator (agr) quorum-sensing system, which coordinates the expression of virulence factors in response to bacterial cell density. Therapeutic approaches focus on neutralizing the toxin using intravenous immunoglobulin (IVIG) or specific antibodies, as well as inhibiting its production through small molecules that target the agr pathway or using protein-synthesis-inhibiting antibiotics.

Other names

SECEnterotoxin type CStaphylococcal enterotoxin type CStaphylococcal enterotoxin C1Staphylococcal enterotoxin C2Staphylococcal enterotoxin C3Staphylococcal enterotoxin C4

Neutralization of toxin activity by antibodies; Inhibition of toxin synthesis via suppression of the accessory gene regulator (agr) system or other regulatory pathways