[Intracellular activity and phagocytability of freshly-isolated strains as parameters of the pathogenicity of tuberculosis mycobacteria].

Phagocytability and the capacity of intracellular multiplication of Mycobacteria tuberculosis isolated from the patients before the treatment and during it (in 1-5 months and later) were studied in the culture of normal peritoneal guinea pig macrophages. A method of quantitative assessment of the capacity to intracellular reproduction of Mycobacteria tuberculosis by determination of the relative activity index in comparison with the standard strain was elaborated. All the cultures of mycobacteria isolated possessed a different extent of intracellular activity and phagocytability. There proved to be no relationship between the intracellular activity indices and the phagocytability of the strains under study. Mycobacteria tuberculosis cultures isolated from the patients during the treatment possessed higher indices of intracellular activity than the initial cultures isolated before the treatment.