A Micropolymorphism Altering the Residue Triad 97/114/156 Determines the Relative Levels of Tapasin Independence and Distinct Peptide Profiles for HLA-A24 Allotypes

Figure 1

HLA-A24/156 variants are expressed at different levels on the surface 721.220 (HLA-/TPN−) or 721.221 (HLA-/TPN+) cells. Flow cytometric analysis of HLA-A24/220 and HLA-A24/221 cells stained with anti-HLA-A9-FITC and w6/32-PE conjugated mAbs. Figures 1(a) and 1(b) show expression of HLA-A24/156 variants on the surface of 721.221 and 721.220 cells, respectively. All the three allelic variants, HLA-A24:0, HLA-A24:0, and HLA-A24:1, showed high levels (~92%) of expression on the surface of 721.221 cells. In 721.220 cells, HLA-A24:0 and A24:1 were expressed at relatively higher levels (~90%) as compared to HLA-A24:0 (~60%).

(a)

(b)