VIP interferes with the differentiation of human DCs and their subsequent maturation. Human DCs generated in the absence (DCcontrols) or presence (DCVIPs) of VIP were stimulated with LPS to induce DC activation/maturation. (A) Cell surface, maturation, and costimulatory markers were analyzed by flow cytometry. Dashed lines in top histograms represent the staining profile with isotype-matched control antibodies. Numbers represent the mean channel fluorescence intensity (MFI) for each phenotypic marker. Histograms are representative of 4 independent experiments. (B) DCs differentiated in the presence of VIP show augmented antigen uptake, evaluated by endocytosis, of FITC-dextran at different times. Results are expressed as fluorescence intensity and are the mean ± SD of 3 experiments performed in duplicate. (C) Differentiation of DCs with VIP modifies their cytokine production after activation. Results are the mean ± SD of 4 experiments performed in duplicate.
