Fig. 1.

Frequency of CD4⁺ T cells is greater in the lung vasculature than parenchyma post-BCG or placebo immunisation. Following BCG immunisation, intravascular staining identified populations of lung parenchymal and lung vascular CD4⁺ T cells. (a) Representative plots from a BCG-immunised mouse showing gating strategy for defining lung parenchymal and vascular populations. (b) Frequency of lung vascular and parenchymal CD4⁺ T cells as a % of total CD4⁺ T cells isolated from the lung. (c) Number of CD4⁺ T cells in the lung parenchyma and vasculature. For both graphs, points represent mean ± SEM (n = 6). Two-way ANOVA with Sidak’s post-test, comparing each time point within the same compartment (shown on graph, ^*P < 0.05, ^**P < 0.01, ^***P < 0.001), BCG with control (no significant differences at any time point) and lung parenchymal with lung vascular (not shown on graph, for all time points frequency and number of lung vascular CD4⁺ T cells exceeded lung parenchymal CD4⁺ T cells in both BCG-immunised and control mice by ^****P < 0.0001).