title: Catalase, a specific antigen in the feces of human subjects infected with Helicobacter pylori.
abstract: Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C(50) chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces.
authors.affiliation: Sagami Research Laboratories, Wakamoto Pharmaceutical Co., Ltd., Ohimachi, Ashigarakami-gun, Kanagawa 258-0018, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Suzuki
authors.forename: Masahiko
authors.initials: M
authors.lastname: Wakasugi
authors.forename: Seigo
authors.initials: S
authors.lastname: Nakaya
authors.forename: Naomi
authors.initials: N
authors.lastname: Kokubo
authors.forename: Masami
authors.initials: M
authors.lastname: Sato
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Kajiyama
authors.forename: Ryoki
authors.initials: R
authors.lastname: Takahashi
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Hirata
authors.forename: Yohji
authors.initials: Y
authors.lastname: Ezure
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fukuda
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimoyama
mesh_terms: D000911:Antibodies, Monoclonal / Q000302:isolation & purification; D000918:Antibody Specificity; D000942:Antigens, Bacterial / Q000032:analysis / Q000302:isolation & purification*; D002374:Catalase / Q000032:analysis / Q000276:immunology*; D002846:Chromatography, Affinity; D003429:Cross Reactions; D005243:Feces / Q000382:microbiology*; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans
chemical_list: D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D002374:Catalase