Heart- and skeletal muscle-specific antigens recognized by trichinellosis patient sera.

The heart can be seriously affected in human trichinellosis, and cardiac involvement can cause death. Experimental infections in rats have suggested the possible participation of immunopathological processes. The aim of the present paper was to investigate the possible presence in trichinellosis patient sera of antibodies recognizing host tissues and particularly the myocardium. Nineteen sera from late period trichinellosis patients, who acquired infection in the Poznan region (Poland), were tested by immunoblot on extracts from normal rat or human heart ventricle wall, spleen, placenta, kidney and skeletal muscle. Patients' sera recognized several antigens that were not recognized by normal sera. On rat and human heart ventricle wall, a high proportion of sera (42%) reacted with a protein of 68 kDa (P < 0.05 compared to normal sera). The reactivity with this antigen, however, was not significantly different in patients with or without cardiac involvement. When sera were tested on skeletal muscle we found that 47% reacted with a protein of 27 kDa and 53% reacted with a protein of 41 kDa (P < 0.05 for both proteins, compared with normal sera). The reactivity against the 68 kDa antigen and against the 27 and 41 kDa skeletal muscle antigens was not observed on kidney, placenta and spleen extracts. Moreover, very few bands were observed on these tissues as compared to heart and skeletal muscle tissues, thus suggesting a high tissue specificity of the reactivity of trichinellosis sera. In conclusion, this study identifies organ-specific autoantibodies in trichinellosis patient sera, their role in the pathogenesis of cardiac involvement being still unclear.