<prompt> a super antigen is a bacterial product thatBinds to B7 and CD 8 co stimulatory moleculesBinds to beta chain of TCR and MCH class 2 molecules at APC stimulating T cell activationBinds to CD4 molecules causing TCells activationIs presented by macrophages to a larger than normal number of T helper CD4 lymphocytes  <response>: Ref Harrison 16e p1920 Superantigens SAgs are a class of antigens that result in excessive activation of the immune system. Specifically it causes non-specific activation of T-cellsresulting in polyclonal T cell activation and massive cytokine release. SAgs are produced by some pathogenic viruses and bacteria most likely as a defense mechanism against the immune system.Compared to a normal antigen-induced T-cellresponse where 0.0001-0.001 of the bodys T-cells are activated, these SAgs are capable of activating up to 20 of the bodys T-cells. Fuhermore, Anti-CD3and Anti-CD28 Antibodies CD28-SuperMAB have also shown to be highly potent superantigens and can activate up to 100 of T cells. 