title: Role of the Helicobacter pylori outer-membrane proteins AlpA and AlpB in colonization of the guinea pig stomach.
abstract: The human gastric pathogen Helicobacter pylori expresses several putative outer-membrane proteins (OMPs), but the role of individual OMPs in colonization of the stomach by H. pylori is still poorly understood. The role of four such OMPs (AlpA, AlpB, OipA and HopZ) in a guinea pig model of H. pylori infection has been investigated. Single alpA, alpB, hopZ and oipA isogenic mutants were constructed in the guinea pig-adapted, wild-type H. pylori strain GP15. Guinea pigs were inoculated intragastrically with the wild-type strain, single mutants or a mixture of the wild-type and a single mutant in a 1: 1 ratio. Three weeks after infection, H. pylori could be isolated from stomach sections of all animals that were infected with the wild-type, the hopZ mutant or the oipA mutant, but from only five of nine (P = 0.18) and one of seven (P = 0.02) animals that were infected with the alpA or alpB mutants, respectively. The hopZ and oipA mutants colonized the majority of animals that were inoculated with the strain mixture, whereas alpA and alpB mutants could not be isolated from animals that were infected with the strain mixture (P < 0.01). Specific IgG antibody responses were observed in all animals that were infected with either the wild-type or a mutant, but IgG levels were lower in animals that were infected with either the alpA or the alpB mutants, compared to the wild-type strain (P < 0.05). In conclusion, absence of AlpA or AlpB is a serious disadvantage for colonization of the stomach by H. pylori.
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, the Netherlands 2Department of Gastroenterology, VU University Medical Center, Amsterdam, the Netherlands 3Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, UK.
authors.forename: Ramon
authors.initials: R
authors.lastname: de Jonge
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, the Netherlands 2Department of Gastroenterology, VU University Medical Center, Amsterdam, the Netherlands 3Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, UK.
authors.forename: Zarmina
authors.initials: Z
authors.lastname: Durrani
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, the Netherlands 2Department of Gastroenterology, VU University Medical Center, Amsterdam, the Netherlands 3Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, UK.
authors.forename: Sjoerd G
authors.initials: SG
authors.lastname: Rijpkema
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, the Netherlands 2Department of Gastroenterology, VU University Medical Center, Amsterdam, the Netherlands 3Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, UK.
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Kuipers
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, the Netherlands 2Department of Gastroenterology, VU University Medical Center, Amsterdam, the Netherlands 3Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, UK.
authors.forename: Arnoud H M
authors.initials: AHM
authors.lastname: van Vliet
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, the Netherlands 2Department of Gastroenterology, VU University Medical Center, Amsterdam, the Netherlands 3Division of Bacteriology, National Institute for Biological Standards and Control, Potters Bar, UK.
authors.forename: Johannes G
authors.initials: JG
authors.lastname: Kusters
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D006168:Guinea Pigs; D016481:Helicobacter Infections / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D013270:Stomach / Q000382:microbiology*
chemical_list: D018829:Adhesins, Bacterial; C470179:AlpA protein, Helicobacter pylori; D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins