Prevention of viral myocarditis with recombinant human leukocyte interferon alpha A/D in a murine model.
Effects of recombinant human leukocyte interferon alpha A/D on experimental myocarditis due to encephalomyocarditis virus were investigated. Plaque reduction assays revealed that 50% of plaque formation in vitro in human amnion (FL) cells was inhibited by interferon alpha A/D (9.7 U/ml) when it was administered 24 hours before infection with the encephalomyocarditis virus. Four week old male DBA/2 mice were inoculated intraperitoneally with 10 plaque-forming units (pfu) of encephalomyocarditis virus. Interferon alpha A/D was administered subcutaneously (10(2) U/g body weight per day in Group 1, 10(3) U/g per day in Group 2 and 10(4) U/g per day in Group 3) starting 1 day before infection. It was also administered starting the same day in Group 4 and 1 day after virus inoculation in Group 5 (10(4) U/g per day in both groups). Control mice were injected with saline solution. Each group consisted of 10 mice; they were killed on day 4 for evaluation. Myocardial virus titers were significantly lower in Group 3 (8.2 +/- 25.2 X 10(2) pfu/mg, p less than 0.05) and Group 4 (3.0 +/- 5.5 X 10(3) pfu/mg, p less than 0.05) than in control mice (5.6 +/- 4.1 X 10(4) pfu/mg). Histologic examination showed extensive myocardial necrosis and cellular infiltration in all control mice, but no myocardial necrosis or cellular infiltration in Group 3 and less severe necrosis and infiltration in Group 4. There were no significant differences in myocardial virus titers or histologic changes between control mice and Group 1, 2 or 5.(ABSTRACT TRUNCATED AT 250 WORDS)
D000818:Animals; D001921:Brain / Q000382:microbiology; D004686:Encephalomyocarditis virus / Q000302:isolation & purification; D004769:Enterovirus Infections / Q000382:microbiology; D006321:Heart / Q000382:microbiology; D006801:Humans; D007370:Interferon Type I / Q000145:classification / Q000627:therapeutic use*; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D009205:Myocarditis / Q000209:etiology* / Q000401:mortality / Q000473:pathology / Q000517:prevention & control; D011994:Recombinant Proteins / Q000627:therapeutic use*
D007370:Interferon Type I; D011994:Recombinant Proteins