Reduced cell-surface expression of MHC class I molecules in HFE C282Y mutant PBMCs. (A) HFE WT (○), C282Y mutant (▿), and H63D mutant (□) PBMCs were surface stained for MHC class I molecules. Results are presented as the gaussian CDF of the MFI obtained in each individual experiment. The asterisk represents a statistically significant difference between the MFI distribution of the C282Y mutants when compared with the WT and H63D cells (Dn = 0.53; P < .01). (B) PBMCs were double-stained with anti–HLA-A, -B, or -C–FITC and anti–CD14-PE mAb. Class I staining MFI in double-positive cells is presented as the CDF. C282Y mutant and WT cells are compared. ^*Statistically significant difference between the MFI distribution of the C282Y mutant cells when compared with the WT cells (Dn = 0.58; P < .001). Sixty-four individuals were studied with the following distribution: 19 WT; 32 C282Y carriers; and 13 H63D carriers.