Extended Data Figure 9. CD40-CD40L interaction between CD4⁺ T cells and DCs ex vivo can occur in an antigen independent manner.

a, Experimental set-up followed in b–e. Two Cd40^G5/G5 DCs populations were individually pulsed with the indicated concentrations of either OVA^323-339 or LCMV-GP^61-80, mixed, and co-cultured for 24 hours with Cd40lg^SrtA/Y CD4-Cre OT-II CD4⁺ T cells. Biotin-LPETG was added during the last twenty min of co-culture at a final concentration of 10 μM, and cells analyzed by flow cytometry. Where indicated, αCD40L or αMHC-II blocking antibodies were added at a final concentration of 150 μg/ml either at the beginning of co-culture (t=0) or 2 hours before analysis (t=22). b, Flow cytometric analysis of DCs pulsed with 1 μM peptides showing biotin labeling. c–e, Percentage of biotin⁺ DCs gated as in b. Data representative of three independent experiments.