EFFECT OF QUARTZ POWDER ON TUBERCLE BACILLI AND PHAGOCYTES

Abstract

It was observed in mice that quartz particles injected subcutaneously stimulated the growth locally of BCG which had been subsequently inoculated intravenously. However, the multiplication of BCG was hardly observed in the site where nonsilicious particles such as bismuth subnitrate were injected. The intravenous administration of quartz particles has been shown to increase the susceptibility of mice to BCG when infected by the intravenous route. In experiments in vitro, no multiplication of BCG was observed in the mononuclear phagocytes ingesting dust particles, whereas silicious particles, such as quartz, sericite, or kaolin destroyed mononuclear phagocytes remarkably. The results obtained from the present experiments suggest that the heavy destruction of mononuclear phagocytes may be one of the causative factors which enhance extensive multiplication of tubercle bacilli in silicotic loci or produce progressive tuberculosis in silicotuberculotic patients.