Figure 6.
IL-12p40 tg mice are resistant to M. tuberculosis infection and able to form granulomas expressing iNOS. (a) Bacterial loads were determined in lungs, liver and spleen 4 weeks after i.v. inoculation with 105 CFU of virulent M. tuberculosis strain H37Rv. Data represent individual values of infected mice (n = 9–10 mice/group). (b and c) Lung sections were stained with H&E at 4 weeks after M. tuberculosis inoculation from control (b) and IL-12p40 tg mice (c) (d and e) Illustration of iNOS immunostaining of lungs at 4 weeks of M. tuberculosis infection and cells expressing iNOS in granulomas from control (d) and IL-12p40 tg mice (e) Ziehl-Neelsen staining of lung lesions showing very low number of acid fast bacilli in control (f) and IL-12p40 tg mice (g) These figures are representative of one experiment with 9–10 mice per group. Original magnification: 400× (b–e) and 800× (f–g).