Susceptibility to pulmonary tuberculosis in Iranian individuals is not affected by compound KIR/HLA genotype

Abstract

Natural killer (NK) cells have distinctive functional capacities that are likely to contribute both to innate and adaptive immunity to Mycobacterium tuberculosis. Killer cell immunoglobulin-like receptors (KIR) and their ligands, i.e. human leukocyte antigen (HLA) class I molecules contribute partly in regulation of NK cell activity. In this study, the impact of compound KIR/HLA genotype on susceptibility to pulmonary tuberculosis (TB) has been evaluated in Iranian individuals. A total of 107 TB patients and 100 matched healthy controls were genotyped for 17 KIR genes and their three major HLA class I ligand groups (-C1, -C2 and -Bw4: -B Bw4(Ile80) , -B Bw4(Thr80) and -A Bw4) by a polymerase chain reaction-sequence-specific primers assay. Various analyses including distribution of KIR and HLA ligand genes and genotypes, frequency of inhibitory and activating KIR+HLA combinations and compound genotype status regarding balance of inhibitory and activating components showed no significant difference between patient and control groups. These findings may suggest that compound KIR/HLA genotype has no major impact on limiting Mycobacterium tuberculosis infection.