Catalase, a novel antigen for Helicobacter pylori vaccination

Abstract

The efficacy of an orogastric vaccine comprised of purified Helicobacter pylori catalase plus the mucosal adjuvant cholera toxin (CT) was examined with both the Helicobacter felis and H. pylori mouse models with BALB/c mice. Native H. pylori catalase (200 g) plus CT was initially used as a vaccine antigen in the H. felis mouse model and protected 80% (8 of 10) of the challenged animals, while all control animals were infected (20 of 20). In a follow-up experiment, recombinant H. pylori catalase plus CT was used for immunization, and groups of mice were challenged with the Sydney strain of H. pylori. Immunization with recombinant catalase protected a significant proportion (9 of 10) of the mice from H. pylori challenge, indicating that this enzyme should be considered as a candidate for a future vaccine. This study provides the first available data on the efficacy of protective immunization with the new Sydney strain of H. pylori in a mouse model. These data also provide indirect evidence that proteins which are normally intracellular, such as catalase, may be present on the surface of H. pylori and thus may provide targets for immunization.

Immunization with Attenuated Salmonella typhimurium Producing Catalase in Protection against Gastric Helicobacter pylori Infection in Mice

“…Immunization with Helicobacter whole-cell extracts or purified components in the presence of mucosal adjuvant effectively prevented H. pylori infection in animal models [7,[12][13][14][15][16]32]. Although the use of a mucosal adjuvant, such as cholera toxin or Escherichia coli labile toxin, is effective in breaking immune tolerance and inducing protective immunity, intestinal toxicity is a serious problem that limits the use of mucosal adjuvants in humans [35,39].…”

“…A mouse-adapted H. pylori strain (Sydney strain 1, SS1) (Courtesy of Professor Adrian Lee, New South Wales University, Sydney, Australia) was cultured as described previously [7]. The attenuated S. typhimurium SL3261 strain used to express the catalase antigen of H. pylori was an aroA transposon mutant derived from the S. typhimurium SL1344 wild-type strain [10].…”

Helicobacter pyloriflagella: antigenic profile and protective immunity

“…Numerous antigens have been examined as potential vaccine candidates, including whole-cell lysate preparations, and subunit vaccines incorporating urease, heat shock proteins, catalase and CagA (Chen et al, 1992;Ferrero et al, 1994Ferrero et al, , 1995Yamaoka et al, 1996;Radcliff et al, 1997). Live vaccine vectors such as adenovirus and Salmonella serovars encoding Helicobacter antigens have also been investigated (Jiang et al, 1999;Bumann et al, 2001).…”

Effectiveness of vaccinationwith recombinant HpaA fromHelicobacter pyloriis influenced by host genetic background

“…Using mouse models, we have shown that an immune-mediated reduction in Helicobacter colonization could be induced by vaccinations of bacterial lysate with adjuvant delivered either prophylactically or even therapeutically after bacterial challenge (Chen et al, 1992;Doidge et al, 1994). We and others have also examined the potential of purified or recombinant single antigens in protective immunity induced by prophylactic and therapeutic vaccination against gastric Helicobacters (Corthesy Theulaz et al, 1995;Ferrero et al, 1995;Lee et al, 1995;Radcliff et al, 1997;Michetti et al, 1999). However, the protection produced by immunizations with either lysate or recombinant antigens generally produces only a reduction in Helicobacter colonization, and a truly effective vaccine remains elusive.…”