CD4⁺ RTEs mediate enhanced Th2 pathology in an acute model of airway inflammation. Purified OT-II TCR Tg CD4⁺CD45.1⁺ RTEs and MN T cells were transferred into B6 hosts on day 0. Hosts were treated intranasally with TSLP and OVA every other day for 14 days. Analysis was performed on day 15. (A) Representative flow cytometry plots show IL-4 and IFN-γ production by transferred Vα2⁺Vβ5⁺ OT-II RTE and MN T cells isolated by BAL after a 5-hour restimulation in vitro in the presence of OVA_323-339 peptide. Numbers represent percentage of cytokine-positive cells in that gate. (B) Graphs show percentage of IL-4⁺ (left panel) and IFN-γ⁺ (right panel) of transferred OT-II RTEs and MN T cells. Each symbol represents 1 individually analyzed mouse. (C) Total number of cells (left) and number of transferred OT-II cells (right) isolated by BAL of immunized hosts that received either CD4⁺ RTEs or MN T cells. Each symbol represents 1 individually analyzed mouse. (D) Differential cells counts from cytospins of BAL fluid. Data are mean ± SD for 2 independent experiments with 6-7 individually analyzed mice per group. *P < .05, **P < .005.