Absence of IL-17 results in impaired lung macrophage activation during vaccine-induced immunity
B6, and Il17−/− were mucosally vaccinated with ESAT61–20 in combination with LT-IIb, rested, challenged with Mtb as described in Figure 1. Formalin-fixed, paraffin embedded lung sections from day 30 Mtb-challenged lungs were analyzed by immunofluorescence for T cell perivascular cuffing (CD3+) and quantified using the morphometric tool of the Zeiss Axioplan microscope and a representative image of typical T cell perivascular cuffing shown (a). The number of CD3+ T cells within the granuloma were quantitated as described under method (b). The mean fluorescent intensity (MFI) of MHC Class II I-Ab expression on lung macrophages was determined by flow cytometry on day 15 from mucosally vaccinated Mtb-infected mice (Vacc), unvaccinated Mtb-infected mice (Un) or uninfected mice (UI) (c). The number of F4/80 macrophages producing iNOS were enumerated on day 30 post infection in formalin fixed lungs by immunofluorescence and a representative picture shown (d). The data points represent the mean (±SD) of values from 4–6 mice (a–d). *, p ≤0.05, ***p≤0.0005. One experiment representative of two is shown. ns-not significant.