Recovery and identification of interferon in the rabbit urine

Antiviral activities of interferons

“…Exogenously administered interferon also disappears quite rapidly. Early works included injection dosage from 300 units to 104 units per animal; the injection route was intravenous and the test animals were either mice or rabbits; the average time for circulating interferon to drop to trace amounts ranges from 5 min to 15 min (Baron et al, 1966b;Finter, 1966;Subrahmanyan and Mims, 1966;Gresser et al, 1967a;Ho, 1967, Bocci et al, 1967.…”

Renal Metabolism of Rabbit Serum Interferon

“…We have now shown that appropriate administration of maleate does not damage glomerular filtration but markedly inhibits luminal reabsorption of glucose and IFN. After intravenous administration of IFN, the amount present in the plasma and hence in the filtrate may exceed the absorption capacity of the tubular cells even in normal conditions as it has been found in the rabbit (Bocci et al, 1967;Ho & Postic, 1967), mouse (Gresser et al, 1967) and man (Emodi et al, 1975;Arvin et al, 1976). This situation can be defined as overflow interferonuria and it may be useful to emphasize that intravenous administration of large amounts of IFN in humans for therapeutic purposes may lead, at least transiently, to considerable and wasteful loss of IFN in the urine.…”

“…Obviously if the concentration of IFN in the tubular fluid is high enough, it can saturate the uptake mechanism and interfe?onuria will ensue. But because the absorption capacity is normally very efficient the interferonuria will be almost negligible and it was this finding (Bocci et al, 1967;Ho & Postic, 1967) that lead to the incorrect conclusion that the catabolic role of the kidney was of little significance. In fact the kidney and specifically the tubular cells appear now to have a major catabolic role.…”

“…If the amount of filtered proteins exceeds the reabsorption capacity, it will in part escape tubular reabsorption and appear in the urine. Indeed the phenomenon of overflow interferonuria was described independently by Bocci et al (1967), by Gresser et al (1967) and by Ho & Postic (1967). However, the involvement of the kidney was not fully appreciated at that time, and because renal physiology has taken great strides during the last decade (Strober & Waldmann, 1974;Brenner et al, 1976), we have considered it worthwhile reappraising the role of the kidney in the metabolism of IFN.…”

Role of Liver in the Inactivation of Interferon

“…After acidification and dialysis until neutralization, serum and urine were usually freeze-dried ( 10). After acidification and dialysis until neutralization, serum and urine were usually freeze-dried ( 10).…”