a OT-II mice were sacrificed and CD4+ T cells were skewed towards a Th2 phenotype in presence of the OT-II peptide. Cells (1 × 106 per mouse) were injected i.v. into the tail vein of naïve WT or PARP-1−/− recipient mice. All mice were subjected to aerosolized OVA challenge daily for 4 consecutive days. Forty-eight hours later, mice were sacrificed and subjected to BAL. BALF were subjected to total cell count. Sera were assessed for OVA-specific IgE (b). BALF were also assessed for the Th2 cytokines IL-4, IL-5, IL-10, and GM-CSF (c) or the Th1 cytokines IL-2 and INF-γ (d). Asterisk difference from control WT mice, p < 0.01; hash difference from WT mice receiving adoptive transfer (WT (+WT Th2), p < 0.01.