Tissue distribution of recombinant mouse interferon-gamma and recombinant human interferon-gamma in mice, rats, hamsters, and monkeys.

Homologous (mouse) and heterologous (human) recombinant interferon-gamma (IFN-gamma) interferons were injected intravenously into C57BL/6 mice. After 5 min, the greatest proportion of the human IFN was found in the liver, whereas no mouse IFN was detected in the liver at this time or later. Similar results were found in rats, hamsters, and cynomolgus monkeys. Thus, the tissue distribution of these two recombinant IFN-gamma in the various species is not determined by species specificity but by the physicochemical characteristics of the molecules.