河北地区健康人群携带幽门螺杆菌的VacA和CagE毒力基因型分析

Study on VacA and CagE genotypes of Helicobacter pylori isolated from healthy people in Hebei

目的探讨河北地区健康人群携带幽门螺杆菌(Helicobacter pylori,Hp)的VacA和CagE基因型分布情况,为当地Hp流行病学研究和胃病预防提供参考。方法从84名健康体检者胃黏膜组织分离培养Hp,提取DNA,利用PCR方法扩增毒力基因VacA的s基因、m基因、i基因以及CagE基因片段,分析健康人群中Hp流行株的基因型,以及Hp菌株VacA和CagE基因型与健康人群血型、年龄、性别的相关性。结果共分离58株Hp,PCR检测VacA基因均阳性,其中VacA基因的s1型阳性率为98.28%,且以s1a亚型为主,占91.38%;m区以m1b和m2亚型为主,占62.08%;i区阳性率为75.86%,以i1为主,占58.62%。毒力基因组合分型以s1m2i1和s1m1i1为主,占46.55%。CagE基因阳性率为89.7%,其中以CagE2亚型为主,占87.93%,CagE1亚型占1.72%。不同年龄、性别人群VacA基因亚型构成差异无统计学意义(P>0.05)。结论河北地区健康人群感染的Hp大多含VacA和CagE基因,其致病性均较高。VacA基因以s1a、m2/m1b、i1为主,cagE以cagE2为主,这可能是当地消化道疾病高发的一个重要原因,因此应重视对健康人群的胃部检查,预防Hp感染。

Objective To study the distribution of VacA and CagE genotypes of Helicobacter pylori isolated from the healthy population in Hebei. Methods H.pylori was isolated from gastric mucosa from 84 healthy people.After H.pylori DNA was extracted,the CagE gene and the virulence gene VacA(including its s,m,and I regions)were amplified using PCR.The genotypes of epidemic H.pylori strains in healthy people were analyzed.The correlation between the VacA and CagE genotype and blood type,age,and gender in healthy people was analyzed. Results Fifty-eight H.pylori strains were isolated from 84 healthy people.The prevalence of VacA was 100%.The VacA s1 gene was detected at a rate of 98.28%,and the s1 agenotype was most prevalent(91.38%).The VacA m gene was detected at a rate of62.08%,and the m1 band m2 genotypes were most prevalent.The VacA I gene was detected at a rate of 75.86%,and the i1 genotype was most prevalent(58.62%).The s1 m2 i1 and s1 m1 i1 genotypes were prevalent(46.55%),and the m1 band m2 subgenotypes of the m gene were prevalent.The prevalence of CagE was 89.7%;CagE2 was highly prevalent(87.93%)while CagE1 was not(1.72%).The prevalence of the VacA and CagE genotypes did not differ significantly by age or gender(P>0.05). Conclusion Highly pathogenic H.pylori is highly prevalent among healthy people in Hebei.The VacA genotypes were mainly s1 a,m2/m1 b,and i1,and the CagE genotype was mainly CagE2.This may be an important reason for the high incidence of gastrointestinal disease in the area.Gastric screening of healthy people in the Hebei area should be conducted in order to prevent the development of gastric diseases.