Rhesus monkey (Macaca mulatta) model of Helicobacter pylori: Noninvasive detection and derivation of specific-pathogen-free monkeys

Background and Purpose: Development of the rhesus monkey model of Helicobacter pylori has been hampered by problems with serodetection and by the difficulty of identifying specific-pathogen (Helicobacter)-free animals. Our purpose was to determine whether detection could be improved and to determine if pathogen-free monkeys could be derived by nursery rearing. Methods: An enzyme-linked immunoabsorbent assay (ELISA) and a [ ¹⁴C]urea breath test were compared to endoscopy to determine H. pylori infection status in rhesus macaques; 18 animals were hand raised in the nursery to determine whether pathogen-free animals could be selected. Results: Helicobacter pylori infection was common in colony-raised young rhesus monkeys and was nearly universal by adulthood. Serodetection, using antigen from rhesus-derived H. pylori strains, was 95% sensitive and 94% specific. The [ ¹⁴C]urea breath test was 96% sensitive and 88% specific for detection of chronic Helicobacter infection in rhesus monkeys. Segregation of newborn animals within the first 24 h of life was a reliable method to obtain pathogen-free rhesus monkeys. Conclusion: Isolation of specific-pathogen- free animals, together with better detection methods, may improve the value of the rhesus monkey model for the study of H. pylori pathogenesis, immune response, and vaccine development.