Therapeutic vaccination against Helicobacter pylori infection with attenuated recombinant Salmonella typhimurium urease B subunit and catalase in mice.
OBJECTIVE
To investigate the effects of oral immunization with attenuated recombinant Salmonella typhimurium urease B subunit and catalase vaccines in the treatment of Helicobacter pylori infection in a H. pylori infected mouse model.


METHODS
Thirty C57BL/6 mice were randomized into three groups and challenged twice with oral administration of H. pylori within 3 days. Four weeks after the second challenge, the mice were immunized by oral administration of attenuated recombinant S. typhimurium urease B subunit (group A), attenuated recombinant S. typhimurium catalase (group B) or saline (group C), and all mice were killed 4 weeks later. The stomachs were collected for a rapid urease test, modified Giemsa staining and quantitative culture to observe the density of H. pylori, hematoxylin-eosin staining was performed to assess the presence of inflammation and lymphocytes from the spleen were used for the lymphoproliferation assay.


RESULTS
The gastric H. pylori density of groups A, B and C was 1.58 x 10(5) c.f.u./g, 4.88 x 10(5) c.f.u./g and 1.92 x 10(6) c.f.u./g, respectively. The H. pylori density was significantly decreased in the therapeutic groups (P < 0.05). No significant inflammation was found in any group of mice. The lymphoproliferation assays of groups A and B were positive.


CONCLUSIONS
Immunization with oral attenuated recombinant S. typhimurium urease B subunit and catalase vaccines is effective in reducing the density of H. pylori colonization.
Li
Guo Qing
GQ
Department of Gastroenterology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
Chen
Min Hu
MH
Zhu
Sen Lin
SL
Chen
Jie
J
Jiao
Zhi Yong
ZY
Chen
Wei
W
Hu
Pin Jin
PJ
D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology*; D002374:Catalase / Q000276:immunology; D016481:Helicobacter Infections / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D012486:Salmonella typhimurium / Q000276:immunology*; D014510:Urease / Q000276:immunology*; D014613:Vaccines, Attenuated / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology
D001428:Bacterial Vaccines; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; D002374:Catalase; D014510:Urease