Figure 1.

MSS induces a mixed T_H2/T_H17 immune lung response. (A) Timeline of the model of exposure to methanogens. Full line represents intranasal instillation of either PBS, MSS or MBS crude extract while dashed line represents day of euthanasia. (B) Flow cytometry gating strategy for the polarity of the effector lung response after ex‐vivo stimulation of lung leukocytes isolated from methanogen‐exposed mice. CD4⁺ T cells were gated from total lung cells and cytokine‐positive cells were analyzed using Fluorescence Minus One (FMO) controls. (C) Severity of the inflammatory lung response after 3 μg MSS exposure was measured using total broncho‐alveolar lavage (BAL) count and differential count. (D) Polarity of the effector response evaluated as number and the % of CD4⁺ cells expressing IFNg, IL‐13 or IL‐17A. (E) Il13 and Il17a expression measured by qRT‐PCR on lung tissue of mice exposed to MSS compared with PBS. (F) MSS‐specific IgG₁ and IgG_2a and total IgE production was measured from serum using ELISA. Results are representative of at least three separate experiments; n = 3–6 mice/group. * = P ˂ 0.05.