ENTE Proteinas are staphylococcal enterotoxins that activate the host immune system by binding to major histocompatibility complex class II and T-cell receptor (TCR) molecules. This interaction forms a ternary complex that activates T lymphocytes and induces the systemic release of proinflammatory cytokines. Enterotoxin type E Protein, S. aureus (His) is the recombinant Staphylococcus aureus-derived ENTE protein, expressed by E. coli , with N-6*His labeled tag.