Modification of exercise-aggravated coxsackievirus B3 murine myocarditis by T lymphocyte suppression in an inbred model.
The effects of T lymphocyte suppression on coxsackievirus B3 (CB3) myocarditis and its augmentation by exercise were determined in this study. Three-week-old male C3H/HeN mice were divided into four groups. Group 1 mice were infected intraperitoneally (IP) on day 0 with CB3 10(2.5) TCID50, were made to swim daily from days 1 to 9, and were immunosuppressed with daily doses of cyclosporine A (25 mg/kg IP) from days -2 to 8, plus 0.1 ml antithymocyte 1.2 IgG 2a monoclonal antibody IP on day 0. Mice in group 2 were infected and made to swim daily from days 1 to 9. Mice in group 3 were infected and immunosuppressed as outlined. Mice in group 4 were infected IP with CB3. Mortality rates during the acute phase of infection (days 1 to 9) were as follows: group 1, 4% (1/25); group 2, 52% (13/25); groups 3 and 4, 0. Overall mortality rates through day 21 were as follows: group 1, 67% (17/25); group 2, 72% (18/25); group 3, 40% (10/25); and group 4, 4% (1/25). Mean viral titers in serum were highest in the immunosuppressed groups throughout the study. Myocardial viral titers (mean log10 TCID50) were higher in group 2 mice than in group 1 on days 6 (10(6.9) vs 10(4.6)) and 9 (10(8.4) vs 10(7)); however, these titers peaked in group 1 mice on day 13 (10(9.7)). Myocardial inflammation, necrosis, and mean heart weight/body weight ratios were lower in group 1 compared with group 2 on days 6 and 9 but were maximal on day 13 in group 1. Neutralizing antibody titers were lower in immunosuppressed mice on days 6 and 9; however, a rebound increase occurred on day 13.(ABSTRACT TRUNCATED AT 250 WORDS)
Cabinian
A E
AE
Department of Medicine, Wayne State University, Detroit, MI.
Kiel
R J
RJ
Smith
F
F
Ho
K L
KL
Khatib
R
R
Reyes
M P
MP
D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D003384:Coxsackievirus Infections; D003524:Cyclosporins / Q000494:pharmacology; D029822:Enterovirus B, Human / Q000276:immunology / Q000302:isolation & purification; D006321:Heart / Q000382:microbiology; D007165:Immunosuppression Therapy; D007518:Isoantibodies / Q000494:pharmacology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009205:Myocarditis / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D009206:Myocardium / Q000473:pathology; D005082:Physical Exertion; D013550:Swimming; D013601:T-Lymphocytes / Q000276:immunology*
D000914:Antibodies, Viral; D003524:Cyclosporins; D007518:Isoantibodies; C035678:anti-Thy antibody