Mycobacterium avium-complex infections in normal and immunodeficient mice.
Specific pathogen-free C57Bl/6 X DBA/2 (B6D2) F1 hybrid mice were challenged aerogenically with M. avium, M. intracellulare and M. scrofulaceum and the resulting lung and spleen infections were followed over a period of several months. Growth of the mouse virulent M. avium 724 and M. intracellulare D673 was more extensive in the susceptible (Balb/c or C57Bl/6) mice than it was in the resistant A/J and B6D2 strains. Oral challenge of normal C57Bl/6 mice with virulent M. avium-complex serotypes resulted in substantial infection of the gut-associated lymphoid tissues, the lungs and spleen. No infection developed when the mice were infected orally with the avirulent MAC serotypes. T-cell depleted Balb/c (nude or Thxb) mice infected with virulent M. avium developed markedly enhanced lung and spleen infections compared to those seen in the immunocompetent controls. T-cell depletion did not potentiate the systemic growth of the avirulent MAC strains. The significance of these growth patterns (especially in the T-cell depleted mouse) is discussed in relation to the development of life-threatening M. avium-complex infections in patients with Acquired Immune Deficiency Syndrome.
D000818:Animals; D004198:Disease Susceptibility; D005260:Female; D007153:Immunologic Deficiency Syndromes / Q000276:immunology*; D008212:Lymphocyte Depletion; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008819:Mice, Nude; D009162:Mycobacterium avium / Q000472:pathogenicity; D013047:Specific Pathogen-Free Organisms; D013601:T-Lymphocytes / Q000276:immunology; D014376:Tuberculosis / Q000276:immunology*; D014774:Virulence