Superantigens are highly potent immunotoxins expressed by pathogenic bacteria such as Staphylococcus aureus and Streptococcus pyogenes. They play a significant role in various human pathologies, including toxic shock syndrome and autoimmune diseases. The structural and functional characteristics of superantigens are crucial for understanding their mechanisms of action and developing effective therapeutic strategies. This research activity aims to investigate the crystal structures of superantigens and their interactions with host immune cells, providing valuable insights into the molecular basis of their immunomodulatory effects.