T cell dependence of macrophage activation and mobilization during infection with Mycobacterium tuberculosis.
Mice made T cell-deficient as adults by thymectomy and lethal irradiation, and infected with Mycobacterium tuberculosis, showed a greatly reduced capacity to develop nonspecific resistance to challenge with a heterologous bacterium. The capacity to develop nonspecific resistance was restored, however, by an infusion of syngeneic thymocytes. Evidence was presented which showed that the capacity of mycobacteria-infected mice to resist a lethal challenge with a heterologous organism rested on the capacity of macrophages existing at the time of challenge to reduce the number of challenge organisms to a sublethal level within 8 h. This antibacterial activity of macrophages was substantially reduced in T cell-deficient mice but could be restored by an infusion of syngeneic thymocytes. It was concluded that T cell-deficient mice have a reduced capacity to mobilize and activate macrophages because of their reduced capacity to respond immunologically to antigens of M. tuberculosis.
D000818:Animals; D003348:Cortisone / Q000494:pharmacology; D005260:Female; D007111:Immunity, Cellular; D007165:Immunosuppression Therapy; D008089:Listeria monocytogenes / Q000276:immunology; D008088:Listeriosis / Q000276:immunology; D008212:Lymphocyte Depletion; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D011828:Radiation Chimera; D011830:Radiation Effects; D013601:T-Lymphocytes / Q000276:immunology*; D013934:Thymectomy; D013950:Thymus Gland / Q000528:radiation effects; D014376:Tuberculosis / Q000276:immunology*
D003348:Cortisone