title: Different Helicobacter pylori strains colonize the antral and duodenal mucosa of duodenal ulcer patients.
abstract: BACKGROUND
  We have investigated the possibility that the same patients may be colonized by Helicobacter pylori strains of different genotypes or phenotypes in the antrum as compared to in the duodenum. The strains were typed for DNA fingerprints, different lipopolysaccharides (LPS), and Lewis antigen expression on the O-side chains of LPS.
  
  
  METHODS
  Polymerase chain reaction (PCR) amplifications using primer sequences (i.e., the Enterobacterial Repetitive Intergenic Consensus [ERIC]) and randomly amplified polymorphic DNA (RAPD) elements were performed to asses chromosomal DNA diversity between H. pylori strains. The expression of different LPS types and Lewis antigens in the various H. pylori isolates were determined by whole bacterial enzyme-linked immunosorbent assays using monoclonal antibodies.
  
  
  RESULTS
  Duodenal ulcer patients had different H. pylori genotypes in the duodenum as compared to in the antrum as shown by ERIC-PCR (44%) and by RAPD-PCR (75%). Different DNA patterns were found among the strains that were isolated from various regions of the duodenum in 4 of 16 patients (25%) as shown by ERIC-PCR and in 8 of 16 patients (50%) as shown by RAPD-PCR. Sixty-three percent of the duodenal ulcer patients had H. pylori strains with a different Lewis antigen phenotype in the duodenum as compared to in the antrum, and 3 of 16 patients (19%) had strains with different Lewis antigens expressed by strains from different duodenal biopsies from the same patient.
  
  
  CONCLUSIONS
  The results suggest that a mixed population of different H. pylori strains with marked variation, both genotypically and phenotypically, colonize the same patient.
authors.affiliation: Department of Medical Microbiology and Immunology, Göteborg University, Sweden. ann-catrin.thoreson@microbio.gu.se
authors.forename: A C
authors.initials: AC
authors.lastname: Thoreson
authors.forename: N
authors.initials: N
authors.lastname: Hosseini
authors.forename: A M
authors.initials: AM
authors.lastname: Svennerholm
authors.forename: I
authors.initials: I
authors.lastname: Bölin
mesh_terms: D016172:DNA Fingerprinting / Q000379:methods; D004269:DNA, Bacterial / Q000032:analysis; D004381:Duodenal Ulcer / Q000382:microbiology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005753:Gastric Mucosa / Q000382:microbiology; D016481:Helicobacter Infections / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007983:Lewis Blood Group Antigens / Q000032:analysis; D016256:Lewis X Antigen / Q000032:analysis; D008070:Lipopolysaccharides / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011706:Pyloric Antrum / Q000382:microbiology*; D019105:Random Amplified Polymorphic DNA Technique
chemical_list: D004269:DNA, Bacterial; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen; C094162:Lewis Y antigen; D008070:Lipopolysaccharides