Proinflammatory cytokines mediate the toxic effects of staphylococcal exotoxins (SE). This study compared the potency of two polyphenols, green tea epigallocatechin gallate (EGCG) and red wine resveratrol (RES), in blocking the pro-inflammatory effects of staphylococcal enterotoxin B (SEB) and toxic shock syndrome 1 (TSST-1). Both EGCG and RES dose-dependently inhibited superantigen-stimulated ...

Superantigens are defined by their ability to stimulate T cells based predominantly on their V beta expression and ability to delete T cells in the thymus when expressed endogenously. We show here that the expression of one endogenous superantigen, Etc-1, is controlled by the expression of the open reading frame region of the 3' long terminal repeat of the mouse mammary tumor proviral gene, Mtv...

Class II major histocompatibility complex (MFIC) molecules present peptides derived from processed antigen to antigen-specific CD4-positive T cells. In addition, class II molecules bind with high affinity another class of antigens, termed superantigens. T cell stimulation by superantigens depends almost exclusively on the V3 segment expressed by the T ceil receptor (TCR). Mapping of the superan...

The conventional paradigm of T cell activation through the TCR states that Lck plays a critical activating role in this signaling process. However, the T cell response to bacterial superantigens does not require Lck. In this study we report that not only is Lck dispensable for T cell activation by superantigens, but it actively inhibits this signaling pathway. Disruption of Lck function, either...

The staphylococcal enterotoxin-like toxins (SETs) are a family of proteins encoded within the Staphylococcus aureus genome that were identified by their similarity to the well described bacterial superantigens. The first crystal structure of a member of the SET family, SET3, has been determined to 1.9 A (R = 0.205, R(free) = 0.240) and reveals a fold characteristic of the superantigen family bu...