Fig. 1.
Potentiating effects of IFN-γ and TNF-α on macrophage anti-Mycobacterium avium-intracellulare complex(MAIC) activity. The result shown is representative of six experiments separately carried out. Peritoneal macrophages of BALB/c (BcgS) mice were infected with high-virulence MAIC N-260 strain and cultured in the absence (□) or presence of IFN-γ (▪) or TNF-α (hatched bar). IFN-γ and TNF-α were added at concentrations of 300 and 1000 U/ml, respectively. Each bar indicates the number of bacterial colony-forming units (CFU) per macrophage culture (mean ± s.e.m.; n = 3). †Significantly smaller than the value of the control macrophages (− cytokine) (P < 0.05; Mann–Whitney test); *smaller than the value of the control macrophages at P < 0.05 by Student's t-test. The recovery of bacterial CFU in culture fluids was < 10% of that recovered from macrophages.