Effects of PARP-1 Deficiency on Th1 and Th2 Cell Differentiation
PARP-1 deficiency does not affect Th1 cell polarization. Naïve CD4 T cells from wild type (WT, filled symbols) and PARP-1KO (KO, unfilled symbols) mice were stimulated with anti-CD3 mAb and either anti-CD28 mAb or rCD80 or rCD86 for 7 days, ((a), (b), and (d)), or for the indicated time points (c). (a) and (c) IFN-γ concentration in culture supernatants as assessed by ELISA. (b) Cells were collected, restimulated with PMA and ionomycin for 6 hours in the presence of brefeldin A and analyzed by flow cytometry to assess the frequency of IFN-γ-producing cells. (c) IFN-γ concentration in cell cultures stimulated with anti-CD3, anti-CD28, IL-12, and neutralizing anti-IL-4 mAb (Th1-polarizing conditions). (d) Cells were stimulated under Th1-polarizing conditions for 7 days and, after restimulation as in (b), analyzed by flow cytometry. Values represent means ± S.E. * for KO versus WT cells. Results were confirmed in three other independent experiments.