Durable alteration of the colonic microbiota by the administration of donor fecal flora.

Goals: To determine whether fecal bacteriotherapy results in a durable beneficial change in the colonic microbiota of patients with flora-related disorders.

Background: Earlier studies have implicated the colonic microbiota in a number of conditions. Administration of a fecal suspension from a healthy individual to an ill individual (fecal bacteriotherapy) can cure Clostridium difficile infection and potentially other diseases.

Natural colonization with Helicobacter species and the development of inflammatory bowel disease in interleukin-10-deficient mice.

Background: The interleukin-10-deficient (IL-10-/-) mice maintained in specific-pathogen-free (SPF) conditions develop typhlocolitis when experimentally infected with Helicobacter species. However, there is limited information regarding the role of Helicobacter species that naturally colonize IL-10-/- mice in typhlocolitis development. The aim of this study was to examine in SPF IL-10-/- mice the association between natural colonization specific Helicobacter species and typhlocolitis development.

Visualization of Helicobacter species within the murine cecal mucosa using specific fluorescence in situ hybridization.

Background: Members of the genus Helicobacter have been associated with colitis development in a number of immunodeficient animal models. While it is known that these organisms can initiate colitis development, the location and spatial distribution of these bacteria within the intestinal tract is currently unknown. In this study, we developed and optimized fluorescence in situ hybridization (FISH) probes specifically for Helicobacter species.

Template DNA ratio can affect detection by genus-specific PCR-denaturing gradient gel electrophoresis of bacteria present at low abundance in mixed populations.

The detection of Helicobacter species by genus-specific polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was compared with that by species-specific PCR in murine intestinal samples. Results suggest that, in samples containing multiple Helicobacter species, genus-specific PCR-DGGE may fail to detect all Helicobacter species present and that this relates to the initial template DNA ratio.

Absence of mucosa-associated colonic Helicobacters in an Australian urban population.

Application of nested PCR for Helicobacter species to 416 samples obtained at colonoscopy from 15 patients with Crohn's disease, 12 with ulcerative colitis, and 43 controls revealed H. pylori DNA in only 6 individuals with no disease association. No other Helicobacter species were detected in ileal or colonic samples.

Detection of Helicobacter colonization of the murine lower bowel by genus-specific PCR-denaturing gradient gel electrophoresis.

Helicobacter genus-specific PCR and denaturing gradient gel electrophoresis can detect and speciate the helicobacters that colonize the lower bowel of laboratory mice. The method's sensitivity is comparable to that of species-specific PCR and may detect unnamed Helicobacter species. This approach should prove useful for commercial and research murine facilities.