In this retrospective study, the influence of donor and recipient KIR-gene content and their respective ligands
including clinical parameters as potential confounding variables on the outcome of 150 acute myeloid leukemia (AML)
patients undergoing allogenic hematopoietic cell transplantation (HCT) from unrelated donors was systematically investigated.
There was no significant influence of KIR ligand mismatching and of donor/recipient KIR haplotype combinations
on overall survival (OS), disease free survival (DSF), non-relapse mortality (NRM) and relapse. Isolated effects of KIR
haplotypes, were detected for acute, chronic Graft versus Host Disease (aGvHD and cGvHD) as well as for the cumulative
incidence of non-relapse mortality and relapse. The incidence of non-relapse mortality was evaluated in donor and recipient
pairs harbouring KIR AA homozygosity (AA/Bx: p=0.038, HR=0.73, 95% CI=0.35-1.46 and AA/AA: p=0.043,
HR=0.64, 95% CI 0.53-1-17). Our data suggest that KIR genotyping may be useful in patients in whom several HLAidentical
unrelated donors can be identified but is probably not necessary for the primary donor selection algorithm.