Staphylococcal enterotoxins (SEs), produced by Staphylococcus aureus, are responsible for significant human disease including both food poisoning and toxic shock syndrome. Two of these enterotoxins, staphylococcal enterotoxins A and B (SEA and SEB) are described as superantigens for their ability to bind to Major Histocompatibility Complex molecules on antigen presenting cells and stimulate a large population of T cells, producing an inappropriate flood of cytokines. Although they are important participants in an immune response, cytokines, when overproduced, lead to toxic shock. Recently SEB has been found to bind to another regulator of the T cell immune response, CD 28. When added to human peripheral blood cells, SEB produces large quantities of IL-2, TNF-A and INF-c. SEs are resistant to heat, acid and proteases making them a common cause of food–borne disease.
List Labs provides for sale SEB produced in a native Staphylococcus aureus. Native toxin has also been treated with formaldehyde to produce a toxoid which has reduced cytokine stimulating activity and immunogenicity when compared with the native toxin. Care must be taken in the design of experiments with the toxoid because although toxicity has been reduced, sufficient toxicity may remain to cause death under certain conditions. Both the toxin and toxoid are handled as Select Agents and Toxins.
More information about SEB can be found on our blog.