HSP70 and HSP90 Differentially Regulate Translocation of Extracellular Antigen to the Cytosol for Cross-Presentation
Figure 5
HSP70 inhibitor blocks both endogenous- and cross-presentation. (a) DC2.4 cells were transfected with a plasmid containing cDNA encoding OVA by electroporation and immediately incubated with the indicated inhibitors. Three hours later, the cells were fixed and incubated with OTI-CD8+ T cells for 24 hours (left panels). Also, DC2.4 cells transfected with an empty plasmid were pulsed with a suboptimal dose of OVA(257–264) peptide ( M) for three hours in the presence of inhibitors (20 M each), fixed and were used as positive controls in the same assay (right panel). (b) DC2.4 cells were incubated with 0.5 mg/mL OVA in the presence of the indicated inhibitors for three hours and fixed. The cells were washed and incubated with OTI-CD8+ T cells for 24 hours (left panel). Also, DC2.4 cells were pulsed with 0.5 mg/mL OVA in the presence of the indicated inhibitors (20 M each) for three hours, fixed and were used as positive controls in the same assay (right panel). The production of secreted IFNγ by T cells in the supernatants was evaluated by ELISA.*; **; ***. The results were confirmed in at least two independent experiments.
