Among 3 anti-hPD-1H mAbs, 1 clone, MIH65, provided specific staining before or after fixing cells that allowed us to use this mAb with either fresh, cryopreserved, nonfixed, or fixed AML BM cells for flow cytometric analyses (Supplemental Figure 3, A and B). The gene discussed is HPD; the disease is acute myeloid leukemia.