[Morphogenesis of chronic granulomatous inflammation in relation to the variability of the biological properties of the causative agent].

The relationship between morphogenesis of granuloma and biological properties of an infectious agent was studied on the model of experimental brucellosis induced by the R strain of Brucella abortus bovis. The inflammatory reaction in the animals infested with the R-strain of Brucella was found to be considerably reduced: the granulomas were smaller and had an appearance of focal accumulations of mononuclear phagocytes without a tendency for transformation into epithelioid and multinuclear giant cells which is typical of the "Bang granulomas" induced by the S-strain of Brucella. This poorly manifested granulomatosis was accompanied by a low level of the cell-mediated immunity. A hypothesis that the development of torpid and asymptomatic clinical forms of an infectious disease (pathomorhosis) is a result of the incomplete realization of phylogenetically evolved inflammatory and immune responses to the infectious agent with altered biological properties has been proposed.