FIGURE 1.

N. brasiliensis infection promotes IL-27(p28) release and IL-27RA-expressing lymphocytes in the lungs.

C57BL/6J wild type (WT) mice were infected s.c. with third stage larvae (L3) of N. brasiliensis (n=500/mouse) or received a mock PBS injection as controls. The inflammatory cytokines or cells were collected by broncho-alveolar lavage (BAL). (A) IL-27(p28) was quantified in BAL fluid by ELISA at the indicated time points (n=3–5 mice/group). (B) Representative flow cytometry gating of CD19 versus CD3 pre-gated on CD45⁺Ly6G⁻ single cell lymphocytes (left panel), and NK1.1 versus CD3 gated on CD19⁻CD3⁻ innate lymphocytes (right panel), on day 2 post-inoculation (p.i.). Frequencies (%) of parent populations are indicated next to each gate. (C) Absolute numbers of lymphocyte populations of CD19⁻CD3⁺ T cells, CD19⁺CD3⁻ B cells, and CD19⁻CD3⁻NK1.1⁺ NK cells on days 0 (PBS-inoculated/uninfected), 1, and 2 p.i. (n=6–9 mice/group). (D) Representative histograms of IL-27RA expression on T cells (left panel), NK cells (middle panel), and B cells (right panel) on day 2 p.i. The dotted black line indicates isotype-FMO control. The frequencies of IL-27RA⁻ and IL-27RA⁺ cells are indicated in the upper left and right corners, respectively. (E) Frequencies of IL-27RA⁺ T cells, NK cells, and B cells on days 1 and 2 p.i. (n=8–9 mice/group from 2 pooled experiments). (F) IL-27RA presence expressed as geometric mean fluorescence intensity (gMFI) on these cells at these time points (n=6 mice/group). (G) Representative histogram of IL-27RA expression on T cells on days 1 and 2 p.i. The dotted black line indicates isotype-FMO control (Ctrl). Each circle indicates an individual mouse (A, E, F). Data are shown as mean ± SEM (A, C, E, F). Data were analyzed by Student’s t-test comparing day 0 vs. day 1 and day 0 vs. day 2 for each cell type (C), one-way ANOVA (A), or two-way ANOVA (E, F), * P<0.05, ** P<0.01, *** P<0.001, **** P<0.0001, ns: not significant.