Filtrable forms of mycobacteria tuberculosis.

An experimental investigation was carried out on 133 guinea pigs. It showed that the chemotherapy of the destructive pulmonary tuberculosis resulted in the culture negativation in the presence of destructive cavities. At the same time, manifestations of antigenemia and specific cellular and humoral immunity were observed. During repeated biological passages, a reversion of the filtrable forms of the tuberculosis agent into the typical bacterial forms took place. That was accompanied by an increase of the antigenemia (from passage to passage) and an increase of the immunological reactivity. It may be suggested that the filtrable forms of the tuberculosis agent have their role in the preservation of the long-term immunity after the infection or after BCG vaccination. On the other hand, the filtrable forms, persisting in the organism, can cause, under favourable conditions, by reverting, a reactivation or a relapse of the tuberculosis disease.