Association of Toll-like receptor-4 (Asp299Gly and Thr399Ileu) gene polymorphisms with gastritis and precancerous lesions

Hum Immunol. 2007 Nov;68(11):901-7. doi: 10.1016/j.humimm.2007.10.006. Epub 2007 Nov 5.

Abstract

A Toll-like receptor-4 (TLR-4) Asp299Gly and Thr399Ileu substitution reduces responsiveness to Helicobacter pylori (H. pylori) lipopolysaccharide. CagA+ strains of H. pylori are known to be associated with gastroduodenal diseases. Therefore we aimed to evaluate association of TLR-4 substitutions and CagA seropositivity with gastritis and precancerous lesions in a northern Indian population. After upper gastrointestinal endoscopy, 130 rapid urease test (RUT)-positive patients with nonulcer dyspepsia (NUD) were included. Patients with NUD were also screened for H. pylori infection using modified Giemsa staining and anti-CagA IgG enzyme-linked immunoabsorbent assay. All patients and 200 asymptomatic control subjects were genotyped for TLR-4 substitutions using polymerase chain reaction-restriction fragment length polymorphism. We observed that frequencies of TLR-4 Asp299Gly variants were comparable between patients and control subjects, and also between positive and negative groups of precancerous lesions in patients. Frequencies of TLR-4 399Ileu allele (8% vs 3%, p = 0.008) and Asp299-Ileu399 haplotype (6.5% vs 3%, p = 0.022) were higher in patients than in control subjects at risk for gastritis (OR = 2.6 and 2.5, respectively). TLR-4 399Ileu allele carriers had higher risk for plasma cell infiltration (p = 0.023, OR = 10.6) that led to atrophy (p = 0.028, OR = 4.2) and intestinal metaplasia (p = 0.009, OR = 4.7). CagA positivity was more frequently associated with lymphoid follicle formation (p = 0.033, OR = 2.53). In conclusion TLR-4 Thr399Ileu substitution may be a risk factor for gastritis and precancerous lesions. CagA positivity may be a risk factor for lymphoid follicle development but not for other precancerous lesions in a northern Indian population.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alleles
  • Antibodies, Bacterial / blood*
  • Antigens, Bacterial / immunology*
  • Bacterial Proteins / immunology*
  • Female
  • Gastritis / genetics*
  • Gastritis / immunology
  • Gastritis / metabolism
  • Gastritis / microbiology
  • Gene Frequency
  • Genetic Predisposition to Disease
  • Genotype
  • Helicobacter Infections / immunology
  • Helicobacter Infections / microbiology
  • Helicobacter pylori / immunology
  • Humans
  • India
  • Male
  • Middle Aged
  • Polymorphism, Genetic*
  • Polymorphism, Restriction Fragment Length
  • Precancerous Conditions / genetics*
  • Precancerous Conditions / immunology
  • Precancerous Conditions / metabolism
  • Precancerous Conditions / microbiology
  • Stomach Neoplasms / genetics*
  • Stomach Neoplasms / immunology
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / microbiology
  • Toll-Like Receptor 4 / blood
  • Toll-Like Receptor 4 / genetics*

Substances

  • Antibodies, Bacterial
  • Antigens, Bacterial
  • Bacterial Proteins
  • TLR4 protein, human
  • Toll-Like Receptor 4
  • cagA protein, Helicobacter pylori