Enhanced T-cell response induced by PGE2-matured MoDCs in cocultures with purified CD3+ T cells is inhibited by OX40L blockage. MoDCs were matured with sCD40L in the presence (■) or absence (□) of PGE2 and pulsed with either TT (A,B) or KLH (C,D) for 48 hours. Freshly isolated purified CD3+ T cells were labeled with CFSE and cocultured with autologous MoDCs at a T-cell/MoDC ratio of 10:1. Where indicated, 5 μg/mL of a neutralizing goat anti–human OX40L antibody or a control goat IgG was added. CD4+ (A,C) and CD8+ (B,D) T-cell proliferation was determined by flow cytometry on day 6 of the coculture by CFSE dilution of live (Sytox Blue negative) cells. Mean values and SEM of 3 independent experiments with different donors are shown.