[通过cagA、vacA和babA2毒力相关基因对幽门螺杆菌临床分离株进行基因分型。在智利患者中首次检测到babA2阳性菌株]

[Genotypying of clinical isolates of Helicobacter pylori by cagA, vacA and babA2 virulence associated genes. First detection of a babA2 positive strain in Chilean patients].

作者信息

García Apolinaria, Barra Ricardo, Delgado Carolina, Kawaguchi Fernando, Trabal Natalia, Montenegro Sonia, González Carlos

机构信息

Laboratorio de Patogenicidad Bacteriana, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile.

出版信息

Rev Med Chil. 2006 Aug;134(8):981-8. Epub 2006 Nov 14.

PMID:17130985

Abstract

BACKGROUND

Helicobacter pylori-associated gastroduodenal diseases depends on host characteristics, environmental conditions and bacterial virulence factors, such as cagA, vacA y babA2 gene products. Moreover, peptic ulcer disease has been related with cagA+, vacAs1m1 strains, while metaplasia and gastric cancer has been associated to cagA+, vacAs1 and babA2+ H pylori strains. Gene babA2 has not yet been described in clinical isolates from Chilean patients.

AIM

To investigate the presence of cagA, vacA (s and m) and babA2 genes in clinical isolates of H pylori from Chilean patients.

MATERIAL AND METHODS

Sixty six isolates from 41 patients were genotyped by PCR, using primers for s1a, s1b, s2, m1, m2, cagA and babA2 genes as previously described.

RESULTS

cagA gene was detected in 16 isolates (24.2%) while vacAs1a, vacAs1b, vacAs2, vacAm1 and vacAm2 were detected in 28 (42.4%), 14 (21.2%), 17 (25.8%), 21 (31.8%) and 29 isolates (43.9%), respectively. One isolate (1.5%) was babA2 positive, being the first isolate with this genotype described in Chile. Besides the babA2+ genotype this clinical isolate also presented cagA+ and vacAs1a which has been related with metaplasia or gastric cancer. Five isolates showed an ulcerogenic profile cagA+, vacAs1m1.

CONCLUSIONS

The results presented indicate the prevalence of vacAs1m1 genotype among the clinical isolates analyzed, and a low frequency of babA2 genotype.

摘要

背景

幽门螺杆菌相关的胃十二指肠疾病取决于宿主特征、环境条件和细菌毒力因子，如cagA、vacA和babA2基因产物。此外，消化性溃疡疾病与cagA +、vacAs1m1菌株有关，而异型增生和胃癌与cagA +、vacAs1和babA2 +幽门螺杆菌菌株有关。在智利患者的临床分离株中尚未描述babA2基因。

目的

调查智利患者幽门螺杆菌临床分离株中cagA、vacA（s和m）和babA2基因的存在情况。

材料与方法

使用先前描述的针对s1a、s1b、s2、m1、m2、cagA和babA2基因的引物，通过PCR对来自41例患者的66株分离株进行基因分型。

结果

在16株分离株（24.2%）中检测到cagA基因，而在28株（42.4%）、14株（21.2%）、17株（25.8%）、21株（31.8%）和29株分离株（43.9%）中分别检测到vacAs1a、vacAs1b、vacAs2、vacAm1和vacAm2。1株分离株（1.5%）为babA2阳性，是智利描述的首例该基因型分离株。除了babA2 +基因型外，该临床分离株还呈现cagA +和vacAs1a，这与化生或胃癌有关。5株分离株显示致溃疡型cagA +、vacAs1m1。