Organ distribution of Corynebacterium parvum labeled with iodine-125.

Administration of iv, ip, single sc, multiple sc, and footpad injections of [125I]Corynebacterium parvum in mice revealed different patterns of radioactive vaccine distribution in various organs. High deposition and retention were found in the liver, spleen, and gastrointestinal tract and less in the lungs, kidneys, thymus, and bone marrow. Control animals given 125I showed very rapid clearance of the isotope and no retention in the organs. The pattern of distribution of [125I]C. parvum could be useful when protocols for clinical trials are designed.