[Choice of models for determining the pathogenic properties of the causative agent of pseudotuberculosis].

The infection of monolayer cultures of HEp-2, HeLa and Vero cells can be used for the quantitative evaluation of the invasiveness of Yersinia, their capacity for intracellular multiplication and cytotoxic action. The oral infection of mice and guinea pigs with Y. pseudotuberculosis permits one to observe initial enteritis and generalized infection accompanied by the multiplication of the microbes and the development of multiple granulomas with abscess formation in the liver and spleen. Administration of the supernatant fluid of the cultures to suckling mice and into the ligated loops of the rabbit small intestine, as well as administration of the native and heated lysates of the cultures into the pad of the mouse paw and into intestinal loops of rabbits have allowed the authors to reveal for the first time that in Y. pseudotuberculosis the production of both thermostable and thermolabile enterotoxins occurs and to confirm that Y. enterocolitica synthesizes only thermostable enterotoxin. For the first time Y. pseudotuberculosis have been found to produce keratoconjunctivitis and generalized infection in guinea pigs as the result of conjunctival infection. The complex of the models used in this study is recommended for the determination of the invasiveness and enterogenicity of Yersinia, and their capacity for intracellular multiplication and generalized infection.