The Effect of DNA Vaccine Induced IgY Against C-Urease in Mice Infected with Helicobacter Pylori

Helicobacter pylori is a gram negative، spiral bacterium that colonizes and infects human gastric mucosal. Infection by these bacteria causes chronic inflammation of stomach leading to stomach and duodenum ulcers. Aim of the present research is to study the effect of IgY purified from eggs yolk of immunized with DNA vaccine of C-urease، a subunit of urease enzyme، in treatment of mice infected with H. pylori.

Inoculums of 109 bacteria in 400µl Brocella broth medium were gavaged into C57BL/6j mice in an alternate day method in a six day period. 400 µl of Brocella broth medium was given to the control mice. Eight weeks after the last inoculation، blood was taken from the mice، and infection rate was analyzed using indirect ELISA method. Severity of inflammation was analyzed by pathological tests. Infected mice were orally treated for 28 days with 60 mg of IgY isolated from hens immunized with DNA vaccine.

ELISA results showed establishment of infection in 53% of the infected mice. Pathological results، confirmed the inflammation in the infected subjects. Significant difference in antibody titer of serum was observed between infected mice treated with IgY and the positive control group.

This study showed that C-urease induced IgY is successful in inhibition of H-Pylori infection in mice model.