title: KIR genotype distribution among symptomatic patients with and without Helicobacter pylori infection: is there any role for the B haplotype?
abstract: Contact of peripheral blood lymphocytes with Helicobacter pylori was proved to induce non- major histocompatibility complex-restricted cytotoxicity and natural killer cells are thought to play an important role in the immunity against H. pylori.
  
  
  OBJECTIVE
  In this research, we investigated any possible association between killer immunoglobulin-like receptors (KIR) genotypes and H. pylori infection.
  
  
  METHODS
  KIR genotype was analysed in 101 Lebanese symptomatic patients (51 H. pylori positive and 50 H. pylori-negative) using the KIR Genotyping SSP kit.
  
  
  RESULTS
  Among the H. pylori-positive patients, the AA, AB and BB genotypical frequencies were, respectively, 43.14%, 41.18% and 15.68% with an A:B ratio of 1.76:1. The AA, AB and BB genotypes frequencies for H. pylori-negative individuals were 18%, 62% and 20%, respectively, with an A:B ratio of 0.96:1. No significant difference between patients and controls was detected.
  
  
  CONCLUSIONS
  We noticed a reduced distribution of A haplotype among the 'H. pylori-negative' patients as compared with the "H. pylori-positive" group. This is the first study in the international literature that targets the correlation between KIR genotypes and H. pylori.
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: R
authors.initials: R
authors.lastname: Mahfouz
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: R
authors.initials: R
authors.lastname: Hoteit
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: N
authors.initials: N
authors.lastname: El Hajj
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: D
authors.initials: D
authors.lastname: Shammaa
authors.affiliation: Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: A I
authors.initials: AI
authors.lastname: Sharara
mesh_terms: D020022:Genetic Predisposition to Disease; D005838:Genotype; D016481:Helicobacter Infections / Q000235:genetics* / Q000276:immunology*; D016480:Helicobacter pylori; D006801:Humans; D007861:Lebanon; D054340:Receptors, KIR / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D054340:Receptors, KIR