Staphylococcal enterotoxin B (SEB) is a potent superantigen produced by certain strains of the bacteria Staphylococcus aureus. It belongs to the family of staphylococcal enterotoxins, which are heat-stable proteins known to cause food poisoning and act as virulence factors in staphylococcal infections. SEB is primarily associated with gastrointestinal intoxication and is often responsible for outbreaks of foodborne illnesses.
This toxin exerts its effects by binding to major histocompatibility complex class II molecules on antigen-presenting cells, thereby stimulating a massive release of proinflammatory cytokines from T cells. This excessive immune response leads to a cascade of symptoms, such as fever, vomiting, diarrhea, and abdominal cramps. In severe cases, SEB exposure can cause systemic effects, including hypotension, shock, and multi-organ failure.
SEB is extremely stable, meaning it can withstand harsh conditions, such as high temperatures and acid environments, making it resistant to food processing and preservation techniques. This contributes to its ability to cause outbreaks through contaminated foods, such as salads, dairy products, and meat products.
Due to its potential for use as a bioweapon, SEB is classified as a category B select agent by the Centers for Disease Control and Prevention (CDC). Research and development of countermeasures against this toxin are of significant importance to prevent and treat staphylococcal enterotoxin B-induced infections and mitigate the potential risks associated with its deliberate use.
