The synergistic effect of presence of KIR2DS3 and/or KIR3DS1 in donor genotype and chronic GVHD occurrence on survival of AML patients after peripheral blood stem cell transplantation

Recent studies have indicated that a potential factor influencing peripheral blood stem cell transplantation (PBSCT) outcome is the presence of donor-derived alloreactive natural killer (NK) cells. This retrospective analysis studied the impact of NK alloreactivity based on the activating KIR، for acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL) patients undergoing non-T-cell depleted HLA-identical sibling PBSCT. In this study، KIR genotypes were determined in 40 recipients with AML and 38 recipients with ALL undergoing non-T-cell depleted HLA-identical sibling PBSCT. Then، overall survival (OS)، disease-free survival (DFS) and relapse were evaluated in the recipients. In AML patients، presence of KIR2DS3 and/or KIR3DS1 in donor genotype and chronic GVHD (cGVHD) occurrence were associated with a two-year OS (P=0. 006 and P=0. 024، respectively) and DFS (P=0. 021، P=0. 033، respectively) in univariate analysis. In these patients، bivariate analysis showed that these factors have synergistic effect on OS (P=0. 01) and DFS (P=0. 001). We found that the presence of KIR2DS3 and/or KIR3DS1 in donor genotype and cGVHD occurrence in recipient are the most important predictors for better survival of AML patients in non-T-cell depleted HLA-identical sibling PBSCT، so that lack of KIR2DS3 and/or KIR3DS1 in donor genotype and non-occurrence of cGVHD in recipient synergistically decrease survival in AML patients.