Transmission of Helicobacter pylori between a human and two dogs: A case report.

BACKGROUND: Whereas non-Helicobacter pylori helicobacters, which are frequently detected in the stomachs of dogs and cats as a source of zoonoses, have attracted considerable attention, the role of pets in H. pylori epidemiology is unclear. In our previous study, an H. pylori infection was detected in the stomach of a dog (Dog 1). Here, we investigated the H. pylori infection status in the female offspring of Dog 1 (Dog 2) and its owner within the same household. MATERIALS AND METHODS: Biopsy specimens were obtained from the dog's owner and tested for H. pylori. DNA from gastric biopsy samples of Dog 1, gastric fluid sediment of Dog 2, and bacteria from the stomach of the owner was obtained, and Helicobacter genus- and species-specific PCRs were performed. Then, sequence analyses of the partial region of the ureAB gene were conducted. RESULTS: Samples from both dogs and the owner reacted positively in the genus-specific PCR and negative in the Helicobacter felis-, Helicobacter bizzozeronii-, and Helicobacter heilmannii sensu stricto-specific PCRs. All three samples also reacted positively in the H. pylori-specific PCR. Sequences of the partial ureAB gene from all subjects were identical. CONCLUSIONS: The results suggested that the two dogs and their owner were infected with an identical H. pylori strain. This report is the first to demonstrate that H. pylori can be transmitted between humans and dogs. Further studies are required to investigate the risk factors for the transmission of H. pylori between humans and dogs from the perspective of preventive epidemiology.

Epidemiological study of gastric Helicobacter spp. in dogs with gastrointestinal disease in Japan and diversity of Helicobacter heilmannii sensu stricto.

Epidemiological and pathological studies of Helicobacter spp. in canine stomachs in Japan were performed to investigate strain specific pathogenicity. Gastric biopsies from 144 dogs with gastrointestinal diseases were evaluated for the presence of Helicobacter spp. using genus and species specific PCRs for Helicobacter felis, Helicobacter bizzozeronii, Helicobacter heilmannii sensu stricto (s.s.) and Helicobacter pylori. PCR indicated that 50/144 (34.7%) dogs were infected with Helicobacter spp. Of the genus positive samples, 21/50 could not be amplified by any of the species specific PCRs. To investigate Helicobacter at the species level, partial ureAB gene sequences from 48/50 genus positive samples were determined; 47 strains were identified. Thirty-five strains from 45 cases were closely related to H. heilmannii s.s. (89-99% sequence similarity), seven strains from seven cases were closely related to H. bizzozeronii (95-99% sequence similarity), three strains from three cases were closely related to Helicobacter felis (86%, 98% and 99% sequence similarity), one strain from one case was closely related to Helicobacter salomonis (99% sequence similarity) and one strain from one case was closely related to H. pylori (99% sequence similarity). Dogs infected with Helicobacter spp. most similar to H. heilmannii s.s. had a higher frequency of moderate to severe gastritis than dogs negative for Helicobacter spp. (P=0.044). In conclusion, the predominant Helicobacter spp. detected in canine stomachs in our study were most closely related to H. heilmannii s.s. and displayed substantial genetic diversity. Infection with Helicobacter spp. may be associated with more severe gastritis in dogs.

Epidemiological study on feline gastric Helicobacter spp. in Japan.

Epidemiological and pathological studies on Helicobacter spp. in feline stomachs in Japan were conducted using genus- and species-specific (H. felis, H. bizzozeronii, H. heilmannii sensu stricto [s.s.] and H. pylori) polymerase chain reactions (PCRs), ureAB gene sequencing and histopathology. PCR results showed that 28 of 56 cats were infected with Helicobacter spp., and H. heilmannii s.s. was the most prevalent species by both PCR (28/28) and ureAB gene sequencing (26/28). Some of the sequences showed high similarities with those from human patients with gastric diseases (99%). There were no significant differences between Helicobacter spp.-positive and -negative cats in the severity of chronic gastritis (P=0.69). This is the first extensive epidemiological study on feline gastric Helicobacter spp. in Japan.

Role of interaction with vinculin in recruitment of vinexins to focal adhesions.

Although vinexin was originally identified as a protein binding to the proline-rich hinge region of vinculin, the functions and biochemical properties of the vinexin-vinculin interaction are not known. Here, we determined the affinity of the vinexin-vinculin interaction using surface plasmon resonance measurements and found that vinexin beta interacts with the C-terminal half of vinculin, which mimics an activated "open" form, with a threefold higher affinity than with the full-length "closed" vinculin. Coimmunoprecipitation experiments showed that cell adhesion on fibronectin enhances the vinexin-vinculin interaction. We also show that the interaction with vinculin is necessary for the efficient localization of vinexin alpha and beta at focal adhesions. These observations suggest a model that "activated" vinculin localized at focal adhesions recruits vinexins to focal adhesions.

Interaction of lp-dlg/KIAA0583, a membrane-associated guanylate kinase family protein, with vinexin and beta-catenin at sites of cell-cell contact.

Vinexin is a recently identified cytoskeletal protein and plays a key role in the regulation of cytoskeletal organization and signal transduction. Vinexin localizes at sites of cell-extracellular matrix adhesion in NIH3T3 fibroblasts and at sites of cell-cell contact in epithelial LLC-PK1 cells. Expression of vinexin promotes the formation of actin stress fiber, but the role of vinexin at sites of cell-cell contact is unclear. Here we identified lp-dlg/KIAA0583 as a novel binding partner for vinexin by using yeast two-hybrid screening. lp-dlg/KIAA0583 has a NH2-terminal coiled-coil-like domain, in addition to four PDZ domains, an Src homology (SH) 3 domain, and a guanylate kinase domain, which are conserved structures in membrane-associated guanylate kinase family proteins. The third SH3 domain of vinexin bound to the region between the second and third PDZ domain of lp-dlg, which contains a proline-rich sequence. lp-dlg colocalized with vinexin at sites of cell-cell contact in LLC-PK1 cells. Furthermore, lp-dlg colocalized with beta-catenin, a major adherens junction protein, in LLC-PK1 cells. Co-immunoprecipitation experiments revealed that both endogenous and epitope-tagged deletion mutants of lp-dlg/KIAA0583 associated with beta-catenin. We also showed that these three proteins could form a ternary complex. Together these findings suggest that lp-dlg/KIAA0583 is a novel scaffolding protein that can link the vinexin-vinculin complex and beta-catenin at sites of cell-cell contact.