DC-targeted TLRLs enhance CD8⁺ T-cell stimulation potential of human DCs in vitro. DCs matured and activated by the various TLRL preparations (NP-DC-SIGN-TLRL, soluble TLRL, NP-Isotype-TLRL) and untreated controls (iDC, irrelevant [irr] peptide) were pulsed with the tumor-associated gp100_280-88 peptide Ag (NP-DC-SIGN-TLRL, soluble TLRL, NP-Isotype-TLRL, and iDC) or irrelevant peptide and cocultured with gp100_280-88-specific naive CD8⁺ T cells. (A) IFN-γ and IL-2 levels were determined in supernatants after overnight culture of DCs and T cells. Part of the T cells were cultured for an additional 4 days to determine the expression levels of the CTL markers (B) perforin and (C) granzyme B by flow cytometry. Three experiments were performed using cells from independent donors, giving similar results. Data represent mean values of one experiment performed in triplicate ± SEM. The x-axis in panels A and C represents the concentration of the respective soluble or encapsulated TLRLs present in the culture medium. Bar graph (B) only shows data obtained at the highest TLRL concentrations tested, 1250 ng/mL of poly I:C in combination with 400 ng/mL of R848. *P < .05 and **P < .01 for the significant difference from soluble TLRL.