Recombinant antigen from Helicobacter pylori urease as vaccine against H. pylori-associated disease.
It is well documented that the enzymatic active site of Helicobacter pylori urease is present in the beta-subunit. An important sequence of 135 amino acids of the beta-subunit was determined from the structure of H. pylori urease and by a homology-based study of the urease of other bacteria and plants. The sequence (UreB) was expressed in Escherichia coli as a recombinant fusion protein with glutathione-S-transferase (GST). Seventeen monoclonal antibodies, UA-1-17, were produced using the UreB-GST as the immunogen. The obtained monoclonal antibodies showed a high specificity to UreB, and some of the MAbs cross-reacted with Jack bean urease. About 70% of the established MAbs displayed an inhibitory effect on the enzymatic activity of the urease. Among them, UA-15 MAb could reduce the activity by 53% and it immunologically binds to the bacterium infecting the human stomach mucosa. The antiserum induced by immunization with a recombinant UreB-GST into rabbits displayed a specific binding to mucosal surfaces of the human stomach infected with the pathogen H. pylori. Moreover, the antiserum suppressed the enzymatic activity of H. pylori urease, while the purified H. pylori urease could not induce such an antiserum.
Fujii
Ryoji
R
Fukuyama Medical Laboratory Co., Fukuyama-city, Hiroshima 720-8510, Japan.
Morihara
Fumiko
F
Fukushima
Keigo
K
Oku
Takashi
T
Hifumi
Emi
E
Uda
Taizo
T
D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology / Q000627:therapeutic use; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use; D000942:Antigens, Bacterial / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D001665:Binding Sites / Q000276:immunology; D005753:Gastric Mucosa / Q000276:immunology / Q000382:microbiology; D005767:Gastrointestinal Diseases / Q000276:immunology / Q000517:prevention & control* / Q000628:therapy; D016481:Helicobacter Infections / Q000276:immunology / Q000517:prevention & control* / Q000628:therapy; D016480:Helicobacter pylori / Q000201:enzymology / Q000276:immunology*; D006801:Humans; D006825:Hybridomas / Q000276:immunology; D051379:Mice; D008969:Molecular Sequence Data; D011487:Protein Conformation; D021122:Protein Subunits / Q000276:immunology; D011817:Rabbits; D011994:Recombinant Proteins / Q000276:immunology; D016415:Sequence Alignment; D014510:Urease / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology*
D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D021122:Protein Subunits; D011994:Recombinant Proteins; D014510:Urease