[The protective activity of the adhesion pili of Yersinia pestis]

Y. pestis adhesion pili (AP) in the native form and in the subunit form, used for immunization in one or two injections in a dose of 12-100 mu g on aluminum hydroxide, did not protect white mice and guinea pigs from experimental Y. pestis infection. The study revealed that AP produced a pronounced cytotoxic effect on macrophages and practically no influence on leukocytes. This result was confirmed in the study of luminol-dependent chemiluminescence and in the analysis of 5'-nucleotidase activity of phagocytes. These data make it possible to regard AP as Y. pestis antimacrophagal pathogenicity factor.