Novel antigens of Helicobacter pylori correspond to ulcer-related antibody pattern of sera from infected patients.

Recently, we reported that the patterns of antibodies to Helicobacter pylori protein antigens in serum may be useful for screening patients at high risk for ulcers (P. Aucher et al., J.

Antibody response of patients with Helicobacter pylori-related gastric adenocarcinoma: significance of anti-cagA antibodies.

The aim of this study was to search for a specific antibody pattern in sera from patients suffering from Helicobacter pylori-related gastric adenocarcinoma (GAC). The serological response of 22 patients suffering from GAC, 31 patients with gastroduodenal ulcer, and 39 asymptomatic subjects was analyzed using immunoblotting performed with three H. pylori strains: strain ATCC 43579; strain B110, isolated from a patient with ulcers; and strain B225, isolated from a patient with GAC.

Phenotypic changes of Helicobacter pylori components during an experimental infection in mice.

The bacterial pathogen Helicobacter pylori is highly adapted to the human stomach and the clinical isolates show a high diversity which could be due to adaptative changes of the strains passing from one host to another. In order to study these variations, experimental infection of mice was developed and provided three out of the eleven tested strains able to infect C57BL/6 mice: the Sydney strain which is known to be well adapted to mice and two freshly isolated strains from infected patients. Mice were orally infected with one of these three strains (infecting strains) and were killed 45 days later.

Use of immunoblot assay to define serum antibody patterns associated with Helicobacter pylori infection and with H. pylori-related ulcers.

Serology has been used worldwide to detect Helicobacter pylori infection. Using an immunoblot assay with an antigen from strain ATCC 43579, we sought to determine the antibodies which were good markers of colonization and the antibody patterns associated with ulcers or atrophy. Out of 98 dyspeptic patients, 41 were colonized by H.

Changes in Helicobacter pylori ultrastructure and antigens during conversion from the bacillary to the coccoid form.

In vitro, Helicobacter pylori converts from a bacillary to a full coccoid form via an intermediate U-shaped form. Organisms with a full coccoid form keep a double membrane system, a polar membrane, and invagination structures. Western blots (immunoblots) of sera from colonized patients show that some high-molecular-mass antigenic fractions are expressed only in coccoids.