Analysis of fibrotic depositions in granulomas in chronic silicotuberculosis in mice

The stimulating effect of silicon dioxide on fibroblast proliferation in granulomas of male CBA mice surpasses that of BCG vaccine mycobacteria. The number of fibroblasts in granulomas after combined treatment with BCG and SiO₂ increased by more than 3 times compared to individual treatment with BCG and by 2 times compared to treatment with SiO₂ alone. In silicosis and silicotuberculosis, collagen and argyrophilic fibers in granulomas during the period from 4 to 6 months after administration of granulomogenic factors occupied more than 90% granuloma volume, which 3-fold surpassed the corresponding parameter in mice infected with BCG vaccine alone. In silicosis, pronounced fibrosis was determined by relatively high proliferative and synthetic activities of fibroblasts, while in silicotuberculosis it was achieved due to significantly higher proliferative activity against the background of lower synthetic activity.