Dendritic cells from CVID patients display impaired differentiation. (A) Differentiation of DCs is impaired in CVID patients. Flow cytometric analysis of the expression of differentiation markers on the surface of 6-day-old monocyte-derived DCs of healthy donors (upper panels), CVID patients (patient 1; middle panels), and selective antibody-deficient patients (patient 1; lower panels). Percentage of cells that are positive for the indicated markers are depicted, and mean fluorescence intensities are indicated in parentheses. (B) Comparison of percentage of cells expressing CD1a, CD83, and CD80 in 12 CVID patients (open circles; numbers 1-12 within each circle correspond to patients' numbers), 6 healthy donors (filled circles), 3 selective antibody-deficient patients (open squares; numbers 1-3 within each square correspond to patients' numbers), and 1 patient with hyper IgM syndrome (open squares with number 4) after differentiation of monocytes for 6 days. The mean values are indicated by a horizontal bar for each marker. Statistical significance as determined by the nonparametric Mann-Whitney test is indicated (*P ≤ .01). (C) Variations among CVID patients with respect to the expression of DC maturation markers in 6-day-old DCs. Each symbol in the figure denotes corresponding CVID patient. MFI indicates mean fluorescence intensity.