The immunological specificity of myosins from cross-striated muscles as revealed by quantitative microcomplement fixation and enzyme inhibition by antisera.

The immunological properties of myosins, especially their muscle-type, class and species specificity, are still controversial. It is the opinion of the authors that the lack of agreement might at least in part be due to the use of contaminated myosins as immunogens and inappropriate methods. We, therefore, purified myosins to a very high degree (approximately 99%) and induced antisera in guinea-pigs. Studies of quantitative microcomplement fixation and enzyme-inhibition by antisera yielded the following results: myosins of cross-striated muscle have an absolute class, a very pronounced muscle-type and a low species specificity. It can be shown that even a very small contamination of myosins with other proteins could seriously hamper the experiments and that the results obtained depend significantly on the immunological methods employed.