Effects of recombinant interferon-gamma and chemotherapy with isoniazid and rifampicin on infections of mouse peritoneal macrophages with Listeria monocytogenes and Mycobacterium microti in vitro.
کلید واژه ها
خلاصه
The effect of recombinant murine interferon-gamma (IFN-gamma) on the growth of Listeria monocytogenes for 4 h and Mycobacterium microti for up to 3 days in monolayers of peritoneal macrophages from BALB/c mice was examined by serial viable counts of cell-associated bacteria. Macrophages pretreated with 10 u IFN-gamma per ml were bacteriostatic and with 100 u or 1000 u per ml were bactericidal against L. monocytogenes. Addition of IFN-gamma 3 days before infection caused monolayers to be bactericidal against M. microti mainly during the first 15 min after infection. This was just evident with 10 u IFN-gamma per ml and greater with 100 u or 1000 u per ml. If IFN-gamma was added when phagocytosis of M. microti was complete, about 2 h after infection, its action was only bacteriostatic, the viable counts remaining stationary while those of unexposed monolayers increased. IFN-gamma 100 u per ml added before infection did not alter the bactericidal activity of rifampicin 10 mg/l, nor did it alter the killing curves for isoniazid 1 mg/l or for rifampicin 10 mg/l if added after completion of phagocytosis.