Virulence of water-induced coccoid Helicobacter pylori and its experimental infection in mice  

作　　者：Fei-FeiShe Jian-YinLin Jun-YanLiu ChengHuang Dong-HuiSu 

机构地区：[1]DepartmentofMicrobiology,MedicalCollegeofWuhanUniversity,Wuhan234007,HubeiProvince,China&DepartmentofMicrobiology,FujianMedicalUniversity,Fuzhou350004,FujianProvince,China [2]DepartmentofMolecularMedicine,FujianMedicalUniversityFuzhou350004,FujianProvince,China [3]DepartmentofMicrobiology,MedicalCollegeofWuhanUniversity,Wuhan234007,HubeiProvince,China [4]DepartmentofMicrobiology,FujianMedicalUniversity.Fuzhou350004,FujianProvince,China [5]DepartmentofImmunology,FujianMedicalUniversity,Fuzhou350004,FujianProvince,China

出　　处：《World Journal of Gastroenterology》2003年第3期516-520,共5页世界胃肠病学杂志（英文版）

基　　金：the Natural Science Fundation of Fujian Province,China,No.C95031

摘　　要：AIM: To explore the virulence and the infectivity of coccoid Helicobacter ppylori(H.pylori) transformed from spiral form by exposure to sterile tap water.METHODS: Three strains of H.pylori, isolated from gastric biopsy specimens of confirmed peptic ulcer, were converted from spiral into coccoid form by exposure to sterile tap water.Both spiral and coccoid forms of H.pylori were tested for the urease activity, and the adherence to Hep-2 cells. The presence of flagella was examined under electron microscopy. In the experimental animal infection, the spiral and coccoid forms of H.pylori originated from the same strain F49 were inoculated intragastrically into BALB/c mice respectively four times at a 3-day interval. Half of the mice from each group were sacrificed at Day 21 and Day 28 after the last inoculation. Histology and H.pylori colonization were detected by urease test of gastric mucosa, cultures of H. pylori,and electron microscopy and so on.RESULTS: The urease activity and the ability of adherence to Hep-2 cells were found to be lower in coccoid H.pylori than that in its spiral form. For example, the transformation in strain F44 led to a significant decrease of the adherence rate and adherence index from 70.0±5.3 % to 30.2±3.5 %(P＜0.01), and from 2.6±0.4 to 0.86±0.3 (P＜0.01),respectively. The flagella of coccoid H.pylori were observed under electron microscope. In the experimental infection in mice, the positive rate of gastric mucosa urease test was 93.8 % (15/16) in the group infected by spiral H.pylori and 50 % (8/16) in the group infected by coccoid H. pylori,and the estimated coccoid H.pylori colony number was 1.75 vs0,56. The positive rates of H. pyloriculture were 87.5 %(14/16) in spiral H. pylori group and 68.8 % (11/16) in coccoid H.pylorigroup. There was no significant difference in either urease test or bacterial culture rate between the groups examined at Day 21 and Day 28 after inoculation. Electron microscopic examination of the samples taken from both groups showed the adherence of H. AIM;AIM.To explore the virulence and the infectivity of coccoid elicobacter pylori(H.pylori)transformed from spiral form byxposure to stedle tap water. METHODS:Three strains of H.pylori,isolated from gastric biopsy specimens ofonfirmed peptic ulcer,were converted from spiral into coccoid form by exposure to sterile tap water. Both spiral and coccoid forms of H.pyloriwere tested for the urease activity,and the adherence to Hep-2 cells.The presence of flagella was examined under electron microscopy.In the experimental animal infection,the spiral and coccoid forms of H.pylori originated from the same strain F49 were inoculated intragastrically into BALB/c mice respectively four times at a 3-day interval.Half of the mice from each group were sacrificed at Day 21 and Day 28 after the last inoculation.Histology and H.pylori colonization were detected by urease test of gastric mucosa,cultures of H.pylori, and electron microscopy and so on. RESULTS:The urease activity and the ability of adherence to Hep-2 cells were found to be lower in coccoid H.pylori than that in its spiral form.For example,the transformation in strain F_(44)led to a significant decrease of the adherence rate and adherence index from 70.0±5.3 % to 30.2±3.5 % (P<0.01),and from 2.6±0.4 to 0.86±0.3(P<0.01), respectively.The flagella of coccoid H.pyloriwere observed under electron microscope.In the experimental infection in mice,the positive rate of gastric mucosa urease test was 93.8 %(15/16)in the group infected by spiral H.pyloriand 50 %(8/16)in the group infected by coccoid H.pylori,and the estimated coccoid H.pylori colony number was 1.75 vs 0.56.The positive rates of H.pyloriculture were 87.5 % (14/16)in spiral H.pylorigroup and 68.8 %(11/16)in coccoid H.pylorigroup.There was no significant difference in either urease test or bacterial culture rate between the groups examined at Day 21 and Day 28 after inoculation. Electron microscopic examination of the samples taken from both groups showed the adherence of H.pylori in spiral, bacillary and coc

关 键 词：水介导 幽门螺杆菌 毒力 动物实验 消化道溃疡 电子显微镜 

分 类 号：R378.99[医药卫生—病原生物学]