Analysis of gene polymorphisms of inhibitory killer cell immunoglobulin-like receptor in patients with inflammatory bowel disease / 中华消化杂志

ABSTRACT

Objective To investigate the gene polymorphism of inhibitory killer cell immunoglobulin- like receptor (iKIR) in patients with inflammatory bowel disease (IBD) and whether the iKIR gene polymorphisms were associated with IBD.Methods Peripheral blood DNA samples were isolated from 100 patients with ulcerative colitis (UC),52 patients with Crohn's disease (CD) and 106 randomly ethnically matched healthy controls.The iKIR gene polymorphisms were analyzed by sequence specific primer polymerase chain reproduction (PCR-SSP).Phenotypic frequency and gene frequency of iKIR gene were calculated,and differences were compared between IBD patients and healthy controls.Results iKIR genes (including KIR2DL1,KIR2DL2,KIR2DL3,KIR2DL4,KIR2DL5,KIR3DL1,KIR3DL2, KIR3DL3) were found to be present in all subjects at different levels.Interestingly,phenotypic frequencies of KIR2DL1 and KIR2DL3 were significantly lower in UC patients than those in healthy controls (P = 0.001),while phenotypic frequencies of KIR2DL2,KIR2DL4,KIR2DL5,KIR3DL1, KIR3DL2 and KIR3DL3 were no difference between UC patients and healthy controls (P>0.05).The phenotype frequency of KIR2DL1 was significantly decreased in CD patients compared with healthy controls (P = 0.007),while phenotypic frequencies of other iKIR were observed to be no significant change between CD patients and healthy controls (P>0.05 ).Conclusions The KIR2DL1 and KIR2DL3 gene phenotype frequencies are decreased in UC patients,which suggests that these gene polymorphisms are associated with the susceptibility of UC,and the polymorphism of KIR2DL1 gene is involved in the susceptibility of CD.