Improved cross-presentation of Gag protein via DEC205 to human T cells. (A) PBMCs from a long-term nonprogressor patient (LB06) were CFSE labeled and cultured 7 days with the indicated sources of HIV Gag p24 antigen (top). At the end of the culture, the cells were restimulated 6 hours with a pool of 50 Gag 15-mer peptides (upper) or without peptides (lower) in the presence of anti-CD28 costimulatory mAb. Data show IFN-γ production by CD8⁺ T cells, most of which have extensively diluted their CFSE label as a result of cell division. (B) As in (A), but the cells are mixtures of MoDCs and autologous T cells from a chronically HIV-infected donor (LB11). The data are displayed as 2 color dot plots to measure CFSE dilution and IFN-γ production in CD3⁺CD8⁺ cells.