ΔY DCs have decreased ability to activate T cells following <i>in vitro</i> infection with <i>Listeria</i>-OVA.

<p>Bone marrow preparations from K^bWT and ΔY mice were cultured <i>in vitro</i> with GM-CSF to develop bmDCs. After 10 days in culture, cells were labeled with CD11c and H-2K^b and analysed by flow cytometry. A, Day 10 bmDCs from K^bWT, ΔY or TAP1^−/− mice were infected with increasing doses of <i>Listeria</i>-OVA for 4 h. After 4 h infection time, extracellular bacteria were removed and DCs were subsequently incubated overnight to allow processing of internalized bacteria. DCs were then incubated with the B3Z T cell hybridoma for 18 h and T cell activation was measured using a CPRG chemiluminescent assay. Uninfected bmDCs from of K^bWT, ΔY or TAP1^−/− mice served as negative controls. B, Data is presented as a fold increase in T cell activation by dividing CPRG absorbance values by background C. uninfected bmDCs from K^bWT, ΔY or TAP1^−/− mice were incubated with indicated doses of soluble whole OVA. Processing of internalized OVA was allowed to take place overnight followed by incubation with B3Z T cell hybridoma for 18 h before measuring T cell activation. BmDCs were also pulsed for 1 h with 1 µM OVA_(257–264)-specific peptide as positive control. Experiments were performed in triplicate and values are presented as means plus SD with Student's <i>t</i> tests * <i>p</i><0.05; ** <i>p</i><0.005; ***<i>p</i><0.0005.