T-cell responses in regulatory T (Treg) cell-specific conditional Bcl6−/− mice after induction of allergic airway disease. Data from the spleens of Treg-specific conditional Bcl6−/− (Bcl6Foxp3−/−) (conditional knockout; cKO) mice and control Bcl6+/+ (Bcl6Foxp3+/+) mice, mated to a Foxp3-GFP-Cre-Rosa26-RFP (FCRR) background and induced to develop allergic airway inflammation by priming with ovalbumin (OVA) -Alum and repeated nasal OVA challenge. (a, b) Spleen cells were stimulated with PMA plus ionomycin along with Golgi-plug for 6 hr, stained for CD4, Foxp3, Gata3, interleukin-4 (IL-4) and interferon-γ (IFN-γ), then analysed by flow cytometry. (c) Since cell fixation destroys the GFP signal, and precludes exTreg cell analysis by ICS, live GFP– RFP+ exTreg cells were obtained by sorting, then stimulated for 16 hr with anti-CD3 and anti-CD28 antibodies before harvest for RNA isolation. Gene expression was assessed by quantitative PCR. n = 4 to n = 7. NS, not significant (P > 0·05), *P < 0·05, **P < 0·01, ****P < 0·001.