KIR2DS3 is associated with protection against acute myeloid leukemia

Interaction between killer cell immunoglobulin-like receptors [KIR] and human leukocyte antigen [HLA] class I molecules is important for regulation of natural killer [NK] cell function. The aim of this study was to investigate the impact of compound KIR-HLA genotype on susceptibility to acute leukemia. Cohorts of Iranian patients with acute myeloid leukemia [AML; n=40] and acute lymphoid leukemia [ALL; n=38] were genotyped for seventeen KIR genes and their three major HLA class I ligand groups [C1, C2, Bw4] by a combined polymerase chain reaction-sequence-specific primers [PCR-SSP] assay. The results were compared with those of 200 healthy control individuals. We found a significantly decreased frequency of KIR2DS3 in AML patients compared to control group [12.5% vs. 38%, odds ratio=0.23, p=0.0018]. Also, the KIR3DS1 was less common in AML group than controls [27.5% vs. 44.5%, p=0.0465, not significant after correction]. Other analyses including KIR genotypes, distribution and balance of inhibitory and activating KIR+HLA combinations, and co-inheritance of activating KIR genes with inhibitory KIR+HLA pairs were not significantly different between leukemia patients and the control group. However, in AML patients a trend toward less activating and more inhibitory KIR-HLA state was observed. Interestingly, this situation was not found in ALL patients and inhibition enhancement through increase of HLA ligands and inhibitory combinations was the main feature in this group. Our findings may suggest a mechanism for escape of leukemic cells from NK cell immunity

Typing of HLA class I by polymerase chain reaction-sequence specific oligonucleotide primer [PCR-SSOP] Technique in Iranian cord blood donors

HLA compatibility between transplant donor and recipient is one of the major determinants of transplant outcome. To determine HLA class I by PCR- Sequence-Specific Oligonucleotide Probe [PCR-SSOP] in cord blood donors. Genomic DNA of 142 cord blood samples registered at the Cord Blood Bank of Iran at Hematology, Oncology, and Bone Marrow Transplantation Research Center, was prepared and HLA class I was determined by the PCR-SSOP. A total of 284 HLA-A alleles was identified of which A*02 and A*24 were the most common. Among 284 HLA-B and HLA-C alleles, B*35, B*51, Cw*4 and Cw*12 were the most frequent alleles in the studied population. Amplification of HLA loci with PCR-SSOP has proved to be a reliable method for HLA-A, -B and -C genotyping