Infection of BM-DC by L lactis (A) CD11c⁺ DCs were infected with L lactis. The infected cells were stained with polyclonal mouse anti–L lactis Ab and FITC-conjugated anti-mouse IgG. Original magnification, × 400. (B) Maturation of BM-DCs induced by L lactis. The L lactis–infected CD11c⁺ DCs were stained with FITC-conjugated MHC class II, CD86, or CD40 mAb followed by analysis of flow cytometry. Lipopolysaccharide (LPS) was used as a positive control. (C) Induction of HIV-specific CTL response in vivo by transfer of IL1403-pHIV–transfected DCs. The L lactis–infected CD11c⁺ DCs were washed and injected intravenously into naive recipient BALB/c mice. One week later, splenocytes were isolated and stimulated with the V3 peptide for 24 hours. IFN-γ–secreting CD8⁺ splenocytes were detected using the ICCS assay. Similar results were obtained from 2 additional experiments. The data represent the average and SEM of 3 mice.