Abstract
To determine abnormal immune regulation in biopsy-proven active and healed myocarditis cases, lymphatic subpopulations in myocardial tissue and peripheral blood were studied. Among 53 cases examined, 19 were active myocarditis (M) and 34 were healing or healed (HM). Five cases of myocarditis were studied sequentially. The percentages of pan T-cells, B-cells, helper/inducer T-cells (Th/i), suppressor/cytotoxic T-cells (Ts/c), etc per total marker positive cells were calculated by use of monoclonal antibodies. In myocardial tissue, the percentage of Th/i was significantly lower in HM than M (p<0.01). The helper/suppressor ratio (OKT4/8) in peripheral blood was 2.43 ± 0.43 (mean ± SE) in M, 1.61 ± 0.19 in HM and 1.34 ± 0.12 in age-matched controls. In 5 progressive studied cases of M, there was a decrease of the helper/suppressor ratio at 1 to 6 months after the myocarditis. It was concluded that subsidence of the immune reaction in myocardium is related to the healing process of myocarditis and may suggest improved prognosis.