| Virulence of water-induced coccoid Helicobacter pylori and its experimental infection in mice. (2003) | |||||||
Abstract | |||||||
| AIM: To explore the virulence and the infectivity of coccoid Helicobacter pylori (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 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 | |||||||
Publication details | |||||||
| |||||||