Immunogenicity and safety of recombinant Helicobacter pylori urease in a nonhuman primate

Dig Dis Sci. 1996 Sep;41(9):1853-62. doi: 10.1007/BF02088757.


Groups of squirrel monkeys (Saimiri spp.), predetermined to be free of Helicobacter infections in the gastric mucosa, were immunized orally with 0.5-4.5 mg of Helicobacter pylori recombinant urease (rUrease) and 25-500 micrograms of Escherichia coli heat-labile enterotoxin (LT) adjuvant. Oral immunization with rUrease resulted in a markedly elevated serum immunoglobulin G (IgG) antibody response with peak levels at 45 days after immunization. No significant gastric inflammation or cytotoxicity was evident in rUrease immunized monkeys as determined by light and electron microscopy. Twenty-five micrograms of LT was a sufficient and safe adjuvant dosage, whereas higher dosages resulted in diarrhea and lethargy. Animals developed a serum IgG antibody response to LT that did not impede the production of anti-rUrease antibody levels. The results of this investigation indicate that rUrease is immunogenic in a nonhuman primate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic* / administration & dosage
  • Animals
  • Bacterial Toxins / administration & dosage
  • Bacterial Toxins / immunology*
  • Biopsy
  • Enterotoxins / administration & dosage
  • Enterotoxins / immunology*
  • Escherichia coli
  • Escherichia coli Proteins*
  • Immunoglobulin G / blood*
  • Microscopy, Electron
  • Saimiri
  • Stomach / cytology
  • Stomach / drug effects
  • Urease / adverse effects
  • Urease / immunology*


  • Adjuvants, Immunologic
  • Bacterial Toxins
  • Enterotoxins
  • Escherichia coli Proteins
  • Immunoglobulin G
  • heat-labile enterotoxin, E coli
  • Urease