功能性主要组织相容性复合体Ⅰ类相关基因A(MICA)-129多态性和血清可溶性MICA水平与溃疡性结肠炎的关系

目的 探讨人类主要组织相容性复合体I类相关基因A(MICA)-129位点多态性及血清可溶性MICA(sMICA)水平与溃疡性结肠炎(UC)的关系.方法 采用聚合酶链反应-直接测序分型(PCR-SBT)方法 检测256例UC患者和460例正常对照者MICA-129的基因多态性;随机选取80例UC患者和90例正常对照者,采用ELISA法测定并比较血清sMICA的浓度差异.结果 UC组的MICA-129的G等位基因和GG基因型频率明显高于正常对照组(76.8%比72.2%,P=0.060;55.9%比46.3%,P=0.016);UC组sMICA水平明显高于正常对照组[(576.47±279.02)ng/L比(182.17±73.11)ng/L,P＜0.001].此外,携带GG基因型的UC患者的sMICA水平明显高于(GA+AA)基因型携带者[(638.87±347.15)ng/L比(507.51±152.87)ng/L,P=0.035].结论 MICA129基因多态性及sMICA水平与UC明显相关,MICA-129基因可能在UC的发病机制中发挥作用.

Abstract：

Objective To investigate the association of the major histocompatibility complex class Ⅰ chain-related antigens A (MICA)-129 gene polymorphism and soluble MICA (sMICA) levels with ulcerative colitis (UC) in Hubei Han nationality. Methods The genetic polymorphism of MICA-129 was examined using a polymerase chain reaction-sequence based test (PCR-SBT) in 256 UC patients and 460 healthy controls. From the above subjects, 80 patients and 90 healthy individuals were randomly selected for determining serum sMICA concentrations by ELISA. Results The frequencies of variant allele (G) and genotype (GG) in MICA-129 gene were significantly higher in the UC patients than in the controls(76. 8%vs 72. 2%, P =0. 060; 55.9% vs 46. 3% ,P =0. 016). Serum sMICA levels were significantly elevated in the patients compared to the controls[(576. 47 ±279. 02) ng/L vs( 182. 17 ±73. 11 ) ng/L,P ＜0. 001]. In addition, the sMICA levels were higher in the patients carrying MICA-129 GG genotypes than in those carrying ( GA + AA) genotypes [( 638. 87 ± 347. 15 ) ng/L vs ( 507. 51 ± 152. 87 ) ng/L, P = 0. 035].Conclusions The genetic polymorphism of MICA-129 and sMICA levels are correlated with the UC patients in Hubei Han nationality. Our findings demonstrate that MICA-129 gene may contribute to the pathogenesis of UC.