Fig 3. Neutrophils from the second wave do not kill mycobacteria in vivo.
(a) Lung tissue neutrophil numbers from individual C57BL/6 mice were determined after flow cytometry analysis on day 1 and 23 after instillation with 5x106 CFU of BCG or an equivalent load of heat-killed (HK) BCG. Data from two independent experiments (n = 8–9), ***P<0.001. (b) C57BL/6 mice (n = 5) were infected with 5x106 CFU of BCG or 103 CFU of Mtb. From day 1 to 42, the numbers of CFU in lungs were determined after bacterial growth on plates. (c-d) The impact of neutrophil depletion on bacterial control was measured by injecting mAb NIMPR14 or similar amounts of IgG2b control mAb into C57BL/6 mice 5, 3 and 1 day before infection with 5x106 CFU of BCG (c) or 103 CFU of Mtb (d) for the first neutrophil wave, or on day 17, 19 and 22 post infection for the second. The number of BCG or Mtb CFU present in the lung was determined on day 1 and 23 post infection. (b-d) The data shown are the mean ± SD of (log10) CFU counts from individual animals (n = 5–6), ** P<0.01