Labeling of Salmonella Typhymurium with iodine-131 to study phagocytic function in rats

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Maria K. Sato, Aldo J. Rodrigues Junior, Edwaldo E. Camargo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 1989
• Subjects: Salmonella typhymurium; Iodine-131; Transplanted spleen; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1590/S0036-46651989000300001; https://doaj.org/article/a453f86c467e42f791a559272bb31163

The present study describes a method for labeling Salmonella typhymurium with iodine-131 to evaluate both the morphological and the functional characteristics of the reticulo-endothelial system. A suspension containing 2 x 10(9) bacteria per ml was labeled with carrier-free Na131I without reductor, with a labeling yield of 46.5 ± 3% and 3.5 ± 1.3% of free Iodine-131. The biodistribution of the labeled bacteria in rats was studied with a large field-of-view scintillation camera equiped with a pinhole collimator. Whole body images were obtained 15 and 30 minutes after intravenous injection of the labeled microorganisms. Images showed accumulation of bacteria in the liver and both normal and transplanted spleens of the animals. Autoradiographs of liver and spleen demonstrated labeled bacteria within the cells of the reticulo-endothelial system. The method described is easy to perform, has a good labeling yield and allows the functional evaluation of the reticulo-monophagocytic system, including transplanted spleens.