Effect of interferon or Propionibacterium acnes on the course of experimentally induced feline infectious peritonitis in specific-pathogen-free and random-source cats.
Seventy-four cats (52 treated and 22 untreated) were evaluated in efficacy studies of interferon (IFN), Propionibacterium acnes, or a combination of these drugs against experimentally induced feline infectious peritonitis (FIP). Cats were given doses of recombinant human leukocyte (alpha) IFN (rHuIFN-alpha), feline fibroblastic (beta) IFN (FIFN-beta) or P acnes at regular intervals before and after inoculation of virulent FIP virus (FIPV). Prophylactic and therapeutic administration of high doses (10(6) U/kg of body weight) or moderate doses (10(4) U/kg) of rHuIFN-alpha, FIFN-beta (10(3) u/kg), or P acnes (0.4 or 4 mg) did not significantly reduce mortality in treated vs untreated cats. However, the mean survival time in cats treated with 10(6) U of rHuIFN-alpha-/kg alone or combined with doses of P acnes was significantly (P = 0.03) increased after inoculation of highly lethal amounts (200 LD100) of FIPV vs survival time in untreated cats. Although P acnes alone was ineffective, there was some indication that a combination of P acnes and high doses of rHuIFN-alpha was more effective than rHuIFN-alpha alone. Seemingly, the efficacy of rHuIFn-alpha treatment was improved in cats challenge-exposed with less FIPV; in 1 trial, 4 of 5 cats (80%) treated with high doses of rHuIFN-alpha survived after inoculation of minimal lethal amounts (0.6 LD100) of FIPV, whereas only 2 of 5 untreated cats (40%) survived. Pretreatment of cats with 10(6) U of rHuIFN-alpha/kg resulted in detectable serum IFN activity 24 hours later; serum IFN activity was not detected in cats pretreated with P acnes, FIFN-beta, or 10(4) U of rHuIFn-alpha/kg.(ABSTRACT TRUNCATED AT 250 WORDS)
Weiss
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Scott-Ritchey Research Program, Auburn University, AL 36849.
Cox
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Oostrom-Ram
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D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D000917:Antibody Formation; D002371:Cat Diseases / Q000378:metabolism / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control*; D002415:Cats; D003332:Coronaviridae; D003333:Coronaviridae Infections / Q000378:metabolism / Q000382:microbiology / Q000401:mortality / Q000517:prevention & control*; D006801:Humans; D007370:Interferon Type I / Q000097:blood / Q000494:pharmacology*; D010538:Peritonitis / Q000378:metabolism / Q000382:microbiology / Q000401:mortality / Q000662:veterinary*; D011425:Propionibacterium acnes; D011897:Random Allocation; D013047:Specific Pathogen-Free Organisms; D013997:Time Factors
D000276:Adjuvants, Immunologic; D007370:Interferon Type I