title: Is the sanctuary where Helicobacter pylori avoids antibacterial treatment intracellular?
abstract: The sanctuary site where Helicobacter pylori evades antimicrobial therapy is unknown, but considerable data exist about an intracellular location for H pylori. Ten H pylori-infected volunteers received standard triple antimicrobial therapy for 2 weeks. Gastric mucosal biopsy specimens were obtained with jumbo forceps on therapy days 0, 3, 14, and 42. Hematoxylin-eosin staining was used for classification of gastritis and the Genta stain for the visualization of H pylori. Immunohistochemical staining was used to detect HLA-DR antigens, human heat shock protein (HSP60), and the bacterial HSP60 antigen. Bacterial HSP60 was expressed on the mucosal surface and within epithelial cells. No such expression of human HSP60 was found, which supports a bacterial origin for the intracellular HSP60. Coexpression of bacterial HSP60 and HLA-DR was always observed, indicating an ongoing local immune response. Infection was cleared on day 14, but when examined 4 weeks after completion of therapy, Genta staining indicated that only five volunteers remained free of H pylori. However, results of immunohistochemical staining were negative at this time for only two volunteers. Disappearance of intracellular expression of bacterial HSP60 remained after therapy and correlated with the intensity of chronic inflammatory cell infiltration. These data are consistent with the intracellular localization of H pylori having a role in inflammation and as a protective strategy against extracellular antibacterial activity.
authors.affiliation: Department of Clinical Microbiology, University Hospital, Uppsala, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Engstrand
authors.forename: D
authors.initials: D
authors.lastname: Graham
authors.forename: A
authors.initials: A
authors.lastname: Scheynius
authors.forename: R M
authors.initials: RM
authors.lastname: Genta
authors.forename: F
authors.initials: F
authors.lastname: El-Zaatari
mesh_terms: D000328:Adult; D000863:Antacids / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D000907:Antibodies, Bacterial / Q000032:analysis / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000032:analysis / Q000276:immunology; D000994:Antitrichomonal Agents / Q000627:therapeutic use; D001729:Bismuth / Q000627:therapeutic use; D018834:Chaperonin 60 / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D004848:Epithelium / Q000382:microbiology / Q000473:pathology / Q000648:ultrastructure; D005260:Female; D005753:Gastric Mucosa / Q000382:microbiology* / Q000473:pathology* / Q000648:ultrastructure; D006684:HLA-DR Antigens / Q000032:analysis / Q000276:immunology; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori / Q000276:immunology / Q000302:isolation & purification* / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use; D008875:Middle Aged; D009942:Organometallic Compounds / Q000627:therapeutic use; D012459:Salicylates / Q000627:therapeutic use; D013752:Tetracycline / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D000863:Antacids; D000900:Anti-Bacterial Agents; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000994:Antitrichomonal Agents; D018834:Chaperonin 60; D006684:HLA-DR Antigens; D009942:Organometallic Compounds; D012459:Salicylates; D008795:Metronidazole; C015715:bismuth subsalicylate; D013752:Tetracycline; D001729:Bismuth