RESUMO
The lipopolysaccharide (LPS) of S. typhimurium has been shown to be significantly detoxified after in vivo irradiation at 500 krad. Radiation is thus a useful method for converting endotoxin into toxoid. The structural alterations in the detoxified LPS are shown to be mainly in the lipid A molecule, resulting in the loss of beta-hydroxymyristic acid.
Assuntos
Endotoxinas/efeitos da radiação , Salmonella typhimurium , Animais , Relação Dose-Resposta à Radiação , Endotoxinas/toxicidade , Lipopolissacarídeos/efeitos da radiação , Lipopolissacarídeos/toxicidade , Camundongos , Polissacarídeos Bacterianos/efeitos da radiação , Polissacarídeos Bacterianos/toxicidade , Doses de RadiaçãoRESUMO
Gamma-irradiation of S. typhimurium cells up to a dose of 500 krad significantly reduces their toxicity. However, the antigenicity of these cells is not altered, which suggests that these cells could be used as a vaccine. The protection offered by the irradiated cells is comparable to that of formalin-treated cells. The radio-vaccine, however, offers an additional advantage of significant detoxification of the endotoxin, thereby minimizing side effects. The lipopolysaccharide extracted from the irradiated S. typhimurium cells offered cross-protection against other Salmonella species tested.