NP-specific CD4 ⁺ T _RM in the lung exhibit a decreased potential to produce IFN-γ and IL-10 following allergic sensitization and challenge. (A) Schematic of the experimental timeline for data in B and C. (B) Representative flow cytometry plots of CD4⁺ T cells isolated from the lung at experimental day 10 or day 40. (C) Summary data of the percentage of YFP⁺ or tdTomato⁺ NP-specific cells and the geometric mean fluorescence intensity of YFP in NP-specific cells as represented in B. Data are pooled from two to five mice per group from two independent experiments. (D) Schematic of the experimental timeline for data in E–H. (E) Representative flow cytometry plots of CD4⁺ T cells isolated from the lung at experimental day 43 and either incubated in media (unstimulated control) or stimulated with PMA/ionomycin for 4.5 h to assess cytokine production potential. (F) Summary data of the percentage of IFN-γ⁺ NP-specific cells and the geometric mean fluorescence intensity of IFN-γ in NP-specific cells as represented in E. Data are pooled from 11–13 mice per group from three independent experiments. (G) Representative flow cytometry plots of CD4⁺ T cells isolated from the lung at experimental day 43 and either incubated in media (unstimulated control) or stimulated with PMA/ionomycin for 4.5 h to assess cytokine production potential. (H) Summary data of the percentage of IL-10⁺ or IL-13⁺ NP-specific cells as represented in G. Data are pooled from 11–13 mice per group from three independent experiments. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Graphs show mean ± SD and data were analyzed by unpaired t test. pfu, plaque-forming units. IAV, influenza A virus. o.p., oropharyngeal. gMFI, geometric mean fluorescence intensity.