title: Helicobacter pylori and Schistosoma japonicum co-infection in a Chinese population: helminth infection alters humoral responses to H. pylori and serum pepsinogen I/II ratio.
abstract: The effects of helminth infection on humoral IgG responses and clinical outcome of gastric Helicobacter pylori infection are unknown. IgG and IgG subclass responses to H. pylori and serum pepsinogen I/II ratio, a marker of gastric atrophy, were investigated in a Schistosoma japonicum prevalent Chinese population. H. pylori, CagA and IgG subclass responses were assayed by ELISA. Serum pepsinogen I and pepsinogen II were assayed by ELISA and the pepsinogen I/II ratio determined. In 150 subjects, infection with S. japonicum and H. pylori was 55.3% and 51.3%, respectively. H. pylori IgG titres and CagA seropositivity were significantly lower (P<0.05) in co-infected subjects, and differences in H. pylori IgG isotype responses were evident. In H. pylori positives, a significantly higher (P<0.05) pepsinogen I/II ratio was observed in co-infected subjects. The difference between S. japonicum positive and negative subjects was only evident in H. pylori CagA seronegative subjects. In conclusion, S. japonicum co-infection with H. pylori is associated with alterations in IgG responses to H. pylori and less gastric atrophy.
authors.affiliation: Molecular Medicine Unit, St James's University Hospital, Leeds LS9 7TF, UK.
authors.forename: Yiqi
authors.initials: Y
authors.lastname: Du
authors.forename: Alison
authors.initials: A
authors.lastname: Agnew
authors.forename: Xiao-ping
authors.initials: XP
authors.lastname: Ye
authors.forename: Philip A
authors.initials: PA
authors.lastname: Robinson
authors.forename: David
authors.initials: D
authors.lastname: Forman
authors.forename: Jean E
authors.initials: JE
authors.lastname: Crabtree
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D015415:Biomarkers; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D005757:Gastritis, Atrophic / Q000378:metabolism / Q000382:microbiology / Q000469:parasitology; D016481:Helicobacter Infections / Q000097:blood* / Q000150:complications / Q000276:immunology*; D016480:Helicobacter pylori / Q000276:immunology* / Q000502:physiology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D020116:Pepsinogen A / Q000097:blood*; D020115:Pepsinogen C / Q000097:blood*; D012549:Schistosoma japonicum / Q000276:immunology* / Q000502:physiology; D012554:Schistosomiasis japonica / Q000150:complications* / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D015415:Biomarkers; D007074:Immunoglobulin G; C080866:cagA protein, Helicobacter pylori; D020115:Pepsinogen C; D020116:Pepsinogen A