[Different pathogenic power of the original BCG strain of the Pasteur Institute and of an isoniazid resistant strain. Histopathological study and significance of local abscesses after inoculation of guinea pig]. / Pouvoir pathogène différent de la souche de BCG historique de l'Institut Pasteur et d'une souche isoniazido-résistante. Etude histopathologique et signification des abcès locaux après inoculation au cobaye

The inoculation into guinea pigs of 10 mg of BCG, obtained either from the Pasteur Institute original strain, or from a mutant isoniazid resistant strain, B1 catalase positive, caused in 40.4% of cases, the onset of abscesses at the point of injection. The frequency and course of these abscesses appear quite different with the two strains, 92.8% with the classical strain, persisting in more than half of the cases after one year, and 23.5% with the INH-resistant strains which regressed within 6 months. Histologically, the structure of the recent abscesses, with a large histiocytic wall often rich in bacteria, and a very cellular necrotic content, appears different from that of old abscesses with a thin wall and a heterogeneous content, calcification with reaction to foreign bodies, and presence of granules due to the persistance of bacteria. The INH-resistant strain is thus in the guinea pig, less aggressive and more rapidly eliminated than the classical Pasteur strain. The course and morphology of abscesses in guinea pigs are very similar to certain old lesions of human tuberculosis and involve, in all strains, phenomena of cell immunity both general and local.

[Changes in the positive P.A.S. reaction of the cytoplasm of giant cells. Role of etiologic factors and the giant cell reaction]. / Variations du caractère A.P.S. positif du cytoplasme des cellules geantes. Rôle des facteurs étiologiques et de la réaction giganto-cellulaire

The search for alpha-amylase resistant, P.A.S. positive cytoplasm has been carried out in 206 giant cell lesions with or without specific inflammatory features and with neogenetic and degenerative plasmodia. It allowed to distinguish: --P.A.S. positivity in inflammatory cells of any nature, however with quantitative variations linked to etiologic factors (pathogen agent and disposition), to site, to the age of the plasmodia, and particularly, with negativation of the reaction in ancient lesions;--negativity of the neogenetic and degenerative plasmodia, save the giant cell articular lesions. Cells containing glycogen particularly (muscular tumors, renal or placental) are easily identified thanks to enzymatic digestion tests. Variations observed in the inflammatory cells seem to be the reflect of an active metabolism bringing about resorption phenomena but probably also immunization processes acting at the level of the cellular microenvironment.