iNKT cell defects are not associated with an alteration of the expression of CD1d on the surface of APCs from patients with HHV-8 MCD. PBMCs from controls (HDs and patients with KS) or patients with HHV-8 MCD were surface stained with CD19 to identify B cells, CD14 and HLA-DR to identify monocytes, and CD27, IgD, IgM, CD21, CD23, CD1d, and CD1c to identify B-cell subsets. (A) Representative histograms showing surface expression of CD1d on CD19⁺ B cells and CD14⁺ monocytes from HDs, patients with KS, and patients with HHV-8 MCD. Scatter plots showing MFI and median of CD1d on B cells from 22 HDs, 15 patients with KS, and 17 patients with HHV-8 MCD, and monocytes from 14 HDs, 7 patients with KS, and 7 patients with HHV-8 MCD. Significant P < .05, Kruskal-Wallis test. (B) Representative histograms displaying CD1d expression on naïve, switched memory, marginal zone, and CD27⁻ memory CD19⁺ B cells in the PBMCs of HDs, patients with KS, and patients with HHV-8 MCD. Scatter plots showing MFI and median of CD1d in each subpopulation of B cells in 22 HDs, 15 patients with KS, and 17 patients with HHV-8 MCD. Significant P < .05, Kruskal-Wallis test.