HISTOCHEMICAL STUDIES ON THE CELLULAR DISTRIBUTION OF ENDOTOXIN OF SALMONELLA EXTERITIDIS IN MOUSE TISSUES

Abstract

The endotoxin of Salmonella enteritidis was prepared and characterized by biological and chemical methods. The fate of the endotoxin in mouse tissues was studied histochemically, using the double-layer method of fluorescein-labelled antibody technique (Coons). The most prominent area where endotoxin was localized is in the cells of the reticulo-endothelial system, particularly the Kupffer cells of the liver and the large round cells of the splenic red pulp. In addition, the endotoxin was detected in the vessel endothelium of various organs. The distribution of the endotoxin was limited to the cytoplasm, but not to the nucleus. Studies on the persistence of the endotoxin in the tissues were performed with an intravenous injection of 0.5 mg per mouse. It remained for approximately 12 weeks in the hepatic Kupffer cells. The minimum dose of the endotoxin which produced detectable localization was 0.01 to 0.02 mg. The relationship of the localization of the endotoxin to the biological activity, including Shwartzman phenomenon and tumordamaging effects, was discussed.