toxin

a poison produced by BACTERIA and by many species of plant and also present in snake venom. In the body, a toxin acts as an ANTIGEN and provokes the production of special ANTIBODIES , called antitoxins. The antitoxins produced may be used in IMMUNIZATION to protect against the disease, as with TETANUS and DIPHTHERIA . An endotoxin is contained within the bacterial cell and released only when the organism dies and decays. Endotoxins do not provoke antitoxin production (see TOXOID ).