儿童幽门螺杆菌感染与HLA-DQB1等位基因遗传多态性研究

目的　研究HLA -DQB1基因位点上是否存在幽门螺杆菌(H .pylori)感染及其相关胃炎的易感基因或抵抗基因,从免疫遗传角度探讨H .pylori感染后临床结局多样性的可能发生机制。方法　对1 999年9月至2 0 0 0年7月上海第二医科大学附属瑞金医院收治的1 3 3例慢性胃炎及80名健康儿童(对照组) ,进行H .pylori检测,应用PCR SSO杂交方法确定其HLA -DQB1等位基因型别。结果　80名对照组儿童中H .pylori阳性3 3名,H .pylori阴性47名;1 3 3例慢性胃炎患儿中,H .pylori阳性85例,H .pylori阴性48例。DQB1 0 3 0 3 2等位基因频率在血清学H .pylori阳性者中低于血清学H .pylori阴性的健康儿童( 1 0 . 61 %vs 2 5. 53 % ,P <0 . 0 5)。DQB1 0 60 2等位基因频率在H .pylori阳性胃炎患儿低于H .pylori阴性胃炎患儿( 4 . 71 %vs 1 2 . 50 % ,P <0 . 0 5)。结论　DQB1 0 3 0 3 2对H .pylori感染可能具有抵抗保护作用,DQB1 0 60 2缺乏可能是H .pylori相关性胃炎发生的宿主遗传因素。

Association of Helicobacter pylori infection with HLA-DQB1 alleles in children

Objective To explore the immunogenetic mechanism of the relation between Helicobactor pylori (H.pylori)-associated diseases and HLA-DQB1, the possible existence of susceptibility or resistance genes to the diseases were examined. Methods 213 subjects were included in the study, 133 with chronic gastritis and 80 normal children(control group). All children were examined for H.pylori infection. HLA-DQB1 genotyping was performed by the polymerase chain reaction-specific sequence oligonucletide(PCR-SSO) method. Results 85 of the 133 chronic gastritis patients and 33 of the 80 controls were H.pylori positive. The allelic frequency (AF) of DQB1*03032 was significantly lower in H.pylori-positive controls than in H.pylori-negative controls(10.61% vs 25.53%, P<0.05). AF of DQB1*0602 was significantly lower in H.pylori-positive gastritis than in H.pylori-negative gastritis(4.71% vs 12.50%, P<0.05). Conclusion DQB1*03032 may contribute to resistance against H.pylori infection and the absence of DQB1*0602 may be a host genetic factor for H.pylori-associated gastritis.