ABSTRACT
BACKGROUND: Staphylococcus aureus TSST-1 is a microbial superantigen which requires interaction between MHC class II molecules and T-cell receptors. To characterize the mechanism of TSST-1 as a superantigen, we investigated the influence of TSST-1 on the binding of T-cell receptor and MHC II. METHODS: For control, A20 cells and lymphocytes from healthy volunteers were measured by the IL-2 bioassay with or withtout TSST-1, which was then purified and confirmed using immunoblot. mRNA for TNF from PBMC was prepared and RT-PCR for mRNA expression was performed. RESULTS: When stimulated by TSST-1(100pg/ mL), lymphocytes produced 135microgram/ml of IL-2 compared to the control A20 cells which produced 5microgram/ ml of 1L-2. TSST-1 was confirmed to be the strong inducer for mRNA expression by RT-PCR. CONCLUSION: The binding to T-cell receptor was enhanced by TSST-1 as confirmed by the bioassay of IL-2. This data may contribute to the understanding of mechanism of cell-toxin interaction.