• Vaccine Name: H. pylori catalase protein vaccine
• Target Pathogen: Helicobacter pylori
• Target Disease: Ulcers
• Vaccine Ontology ID: VO_0011513
• Type: Subunit vaccine
• Status: Research
• Antigen: H. pylori catalase
• katA gene engineering:
  • Type: Recombinant protein preparation
  • Description: When required for use as a vaccine antigen, H. pylori was harvested from plates with 0.1 M phosphate-buffered saline (PBS), pelleted by centrifugation, and disrupted by sonication. The sonicate was stored at 220°C until use. Purified catalase was obtained by the method of Hazell et al. (11). Briefly, H. pylori cells were harvested with 0.1 M sodium phosphate buffer (pH 7.2), centrifuged, and then resuspended in the buffer. Cells were disrupted by sonication, cellular material was removed by centrifugation (5 min, 10,000 3 g), and then the supernatant was collected and filtered (0.22-mm-pore-size filter). Catalase was eluted by the creation of a gradient with 1 M NaCl in 0.01 M sodium phosphate buffer. The purified catalase was then filter sterilized, stored at 4°C, and protected from light (Radcliff et al., 1997).
  • Detailed Gene Information: Click Here.
• Adjuvant:
  • Adjuvant name:
  • VO adjuvant ID: VO_0000143

Mouse Response

• Host Strain: BALB/c
• Vaccination Protocol: Groups of mice were dosed orogastrically on days 0, 7, 14, and 21 with 200 mg of purified recombinant catalase plus 10 mg of CT, 1 mg of H. pylori 921023 sonicate plus 10 mg of CT, 1 mg of E. coli XLOLR sonicate plus 10 mg of CT, or PBS alone or were left unimmunized and unchallenged. One week after the last immunization dose, animals from the catalase plus CT and untreated groups were bled to obtain prechallenge sera (Radcliff et al., 1997).
• Challenge Protocol: Two weeks after the last immunization dose, mice were challenged with three orogastric doses of live H. pylori SS1 cells (;107 organisms/dose) 2 days apart to ensure all animals were infected. After a further 2 weeks, the animals were killed and assessed for H. pylori infection (Radcliff et al., 1997).
• Efficacy: 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 (Radcliff et al., 1997).