RT Journal Article SR Electronic(1) A1 Bino, Tamar A1 Edery, Habib A1 Gertler, Arieh A1 Rosenberg, HagaiYR 1982 T1 Involvement of the Kidney in Catabolism of Human Leukocyte Interferon JF Journal of General Virology, VO 59 IS 1 SP 39 OP 45 DO https://doi.org/10.1099/0022-1317-59-1-39 PB Microbiology Society, SN 1465-2099, AB SUMMARY The metabolic fate of human leukocyte interferon (HuIFN-α) was studied after intravenous injection into rats and cynomolgus monkeys. At various intervals the animals were sacrificed and the HuIFN-α content determined in serum and various tissues. HuIFN-α quickly disappeared from the circulation and was found mainly in the kidneys, in which levels were at least 7- to 10-fold higher than in the liver, spleen, lungs, heart, brain and muscles. No interferon was detected in urine. Subcellular fractionation of kidney revealed that the mitochondrial-lysosomal fraction (15000 g) had a high HuIFN-α content. It was also found that HuIFN-α was rapidly inactivated by two types of proteinases found in the lysosomal fractions of rat, monkey and human kidneys, with an optimal pH of 3 to 4. The inactivation was partially inhibited by either pepstatin or leupeptin. Inactivation was totally prevented by a mixture of both inhibitors. Since it is known that interferon is scantily excreted in urine, our findings suggest that the kidney serves as a main site for its degradation., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-59-1-39