MHC expression profiles of human iPSCs and iPS-HPCs. Parental fibroblasts, iPSCs, iPS-HPCs, hESCs, ESC-HPCs, and UCB-CD34⁺ cells (control) were stained with anti–HLA-ABC, HLA-DR, HLA-G, and HLA-E antibodies. The gray histograms indicate the isotype control. These data show that reprogrammed human iPSCs exhibit low expression of HLA-ABC compared with parental fibroblasts, whereas the expression of other molecules was not significantly different. The expression of the MHC molecules on iPSCs is very similar to that of hESCs. This pattern is also seen in iPS-HPCs and hESC-HPCs. However, the nonclassical MHC molecule HLA-G is upregulated after differentiation. All cell types expressed HLA-E. These data are representative of 7 experiments.