CD4⁺ and CD8⁺ T-cell proliferation and cytokine secretion in response to antigen presentation by CD11b⁺ MHCII^high CDC-like cells. BST2^high PDCs and BST2^low IEC-SN DCs were pulsed with OVA peptide and cocultured with CFSE-labeled CD4⁺ OT II T cells or were pulsed with OVA protein and cocultured with CD8⁺ OT I T cells for 4 days. Proliferation was determined by CFSE dilution, and intracellular IFN-γ was measured by FACS after stimulation with PMA/ionomycin (A, mean ± SD, n = 3). *P < .05. PDCs, BST2^high IEC-SN PDCs, BST^low IEC-SN DCs, splenic CD8α⁺ DCs, and splenic CD8α⁻ DCs were cocultured with OT I T cells in the presence of OVA protein. As control, PDCs were cocultured with OT I T cells in the absence of antigen. After 4 days, proliferation was determined by CFSE dilution, and intracellular IFN-γ and IL-2 were detected by FACS after restimulation with PMA/ionomycin (B, results of 1 representative of 2 experiments are shown).