SUPERANTIGENS AND PSEUDOSUPERANTIGENS OF GRAM-POSITIVE COCCI

Superantigens use an elaborate and unique mechanism of T lymphocyte st imulation. Prototype superantigen are the pyrogenic exotoxins produced by Staphylococcus aureus and Streptococcus pyogenes. Many candidate p roteins of bacterial, viral and protozoal origin have recently been re ported to be superantigens. In most cases the evidence that these prot eins are in fact superantigens is highly indirect. In this review the evidence that grampositive cocci produce superantigens other than the pyrogenic exotoxins is critically discussed. Evidence in described dem onstrating that the epidermolytic toxins of Staphylococcus aureus and the pyrogenic exotoxin B and M-proteins of Streptococcus pyrogenes are not superantigens. Criteria are described for acceptance of a candida te as a superantigen.