Candidate Helicobacter pylori antigens for serologic screening

Helicobacter pylori is a gram negative, spiral shaped bacterium which colonize the gastric mucosta of humans. It induces several gastrointestinal complicatiobs ranging from mild gastritis (asymptomatic) to peptic ulcers and even gastric malignancies. The incidence of H.pylori infection in the developed countries ranges from 30-50% of the population, whereas that of developing countries such as Iran reaches 80-90% of the general population. Due to high prevalence of Hp infection in our country, early stage detection in needed for subsequent eradication therapies. Hp positivity can be detected according to various diagnostic tests. Biopsy culturing and rapid urease test (RUT) are the most reliable ones which show current Hp infection and can detect Hp positive cases if proper sampling in performed. Application of immunological assays in screening host responses to Hp infection in growing. Different experiments have been performed to detect the most reliable antigens of Hp which can be used in these assays. Sonicated whole cell antigens are the most popular option due ti its simple preparation but it has the disadvantage of cross reacting with proteins from other bacteria.On the other hand, preparing recombinant from of Hp virulence markers (CagA and VacA) it a new approach in development of specific assays in screening high risk Hp-infected individuals. Inclusion of reliable diagnostic tests into the routine check-ups will provide secure means for controlling the population health and devising appropriate preventive and therapeutic regimens. In this study, various molecular weight antigene fractions from Helicobacter pylori were prepared and tested for specificity and reliability in antigene specific western blotting and ELISA.

Keywords:

Helicobacter pylori , ELISA , western blot , antigens , diagnostic test