title: Recombinant interferon-gamma and chemotherapy with isoniazid and rifampicin in experimental murine tuberculosis.
abstract: Viable bacterial counts in the lungs and spleens of mice infected intravenously with Mycobacterium tuberculosis, strain H37Rv were reduced by intravenous recombinant murine interferon-gamma (IFN-gamma) 1000-5000 u, but not by 200 u. Reduction in counts was greatest when IFN-gamma was given 1 day before infection and was not increased by additional doses in the preceding 2 days. The effect was complete in 1 day and was not increased by successive doses during the next week. Giving IFN-gamma in multilamellar liposomes further reduced the spleen viable counts, but this appeared due to the liposomes themselves and not to encapsulation of IFN-gamma within them. Only a minimal reduction in organ viable counts, not statistically significant, occurred when IFN-gamma was given 5 days after infection. Although IFN-gamma alone and isoniazid 25 mg/kg alone reduced the organ viable counts, combined treatment with IFN-gamma and isoniazid was no more bactericidal than isoniazid alone. Similarly, the bactericidal activity of rifampicin 25 mg/kg was not increased by simultaneous administration of IFN-gamma. There seems little likelihood that IFN-gamma would increase the efficacy of the early stages of the chemotherapy of tuberculosis.
mesh_terms: D000818:Animals; D004359:Drug Therapy, Combination; D007371:Interferon-gamma / Q000008:administration & dosage*; D007538:Isoniazid / Q000627:therapeutic use*; D008168:Lung / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D009169:Mycobacterium tuberculosis / Q000254:growth & development; D012293:Rifampin / Q000627:therapeutic use*; D013154:Spleen / Q000382:microbiology; D013997:Time Factors; D014376:Tuberculosis / Q000188:drug therapy / Q000382:microbiology / Q000628:therapy*
chemical_list: D007371:Interferon-gamma; D007538:Isoniazid; D012293:Rifampin