Clinical relevance of the Helicobacter pylori gene for blood-group antigen-binding adhesin.
Infection with Helicobacter pylori is associated with different human gastric diseases. Biochemical studies, in vitro adherence assays, and in vivo animal models revealed that epithelial attachment of H. pylori can be mediated by the blood-group antigen-binding adhesin (BabA) targeting human Lewis(b) surface epitopes. Studies with transgenic mice expressing the Lewis(b) epitope have shown that such attachment can alter disease outcome. In the current study, the presence of the babA2 gene encoding the adhesin was investigated in clinical isolates from a German population by using PCR and reverse transcription-PCR. A positive genotype was correlated to allelic variations in the genes encoding VacA and CagA and also to the prevalence of duodenal ulcer, distal gastric adenocarcinoma, mucosa-associated lymphoid tissue lymphoma, and antral gastritis. The presence of babA2 was significantly associated with duodenal ulcer (P = 0.0002) and adenocarcinoma (P = 0.033). In contrast, type 1 strains (vacAs1- and cagA-positive) were associated with only duodenal ulcer (P = 0.004) but not adenocarcinoma (P = 0.235). Genotype presence of babA2, vacAs1, and cagA ("triple-positive" strains) showed a highly significant correlation to the prevalence of ulcer (P = 0.000002) and adenocarcinoma (P = 0.014) and discriminated significantly better between disease outcome than did the current type 1 classification. These results indicate that the babA2 gene is of high clinical relevance and would be a useful marker to identify patients who are at higher risk for specific H. pylori-related diseases.
Gerhard
M
M
Department of Medicine II, Technical University of Munich, 81675 Munich, Germany.
Lehn
N
N
Neumayer
N
N
Borén
T
T
Rad
R
R
Schepp
W
W
Miehlke
S
S
Classen
M
M
Prinz
C
C
D018829:Adhesins, Bacterial / Q000235:genetics* / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D001324:Autoantigens / Q000276:immunology*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D004247:DNA; D005798:Genes, Bacterial; D005838:Genotype; D016480:Helicobacter pylori / Q000235:genetics*; D006801:Humans; D007983:Lewis Blood Group Antigens / Q000276:immunology*; D051379:Mice; D008822:Mice, Transgenic; D016133:Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid; D013272:Stomach Diseases / Q000382:microbiology
D018829:Adhesins, Bacterial; D001324:Autoantigens; C400429:BabA protein, Helicobacter pylori; D002352:Carrier Proteins; D007983:Lewis Blood Group Antigens; D004247:DNA