Comparative Potency of Green Tea and Red Wine Polyphenols in Attenuating Staphylococcal Superantigen-Induced Immune Responses

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 Tcell proliferation with IC50 of 20 μM and 30 μM, respectively. Both polyphenols blocked the production of interleukin 1β, interleukin 6, tumor necrosis factor, gamma interferon, interleukin 2, monocyte chemotactic protein 1, macrophage inflammatory protein (MIP)-1, and MIP-1 by SE-stimulated human peripheral blood mononuclear cells (PBMC). SEBand TSST-1-induced NF-κB activation in PBMC was also significantly reduced by EGCG and RES. These results suggest that polyphenols have potent immunosuppressive effects counteracting the host inflammatory cascades induced by superantigens and might be used therapeutically to mitigate the pathogenic effects of microbial superantigens.