title: TLR4 single-nucleotide polymorphisms alter mucosal cytokine and chemokine patterns in Mexican patients with Helicobacter pylori-associated gastroduodenal diseases.
abstract: Helicobacter pylori is associated with peptic ulcer and gastric adenocarcinoma. Toll-like receptors (TLRs) participate in H. pylori recognition, and single-nucleotide polymorphisms (SNPs) in TLRs are associated with impaired immune response. We aimed to evaluate the association of TLR2/R753Q and TLR4/D299G/T399I SNPs with gastroduodenal diseases; and study the effect of SNPs on cytokine and chemokine expression in the gastric mucosa. Study included 450 Mexican patients with gastroduodenal diseases. SNPs in TLRs 2 and 4 genes were analyzed by allele-specific PCR. Cytokines and chemokines were assessed by qRT-PCR and immunoassay. TLR4/D299G/T399I polymorphisms were more frequent in duodenal ulcer and showed a trend in gastric cancer, when compared with non-atrophic gastritis. Patients with TLR4 polymorphisms expressed significantly lower levels of IL-1beta, IL-6, IL-8 and GRO-alpha; and higher levels of TNF-alpha, IL-10, MCP-1 and MIP-1alpha . SNPs in TLR4 gene had an association with severe H. pylori-associated disease and with modified pattern of inflammatory cytokines and chemokines in the gastric mucosa. These results suggest that TLR4 SNPs contributes importantly to the clinical outcome of H. pylori infection.
authors.affiliation: Unidad de Investigación en Enfermedades Infecciosas, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, IMSS, Mexico City, México.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Trejo-de la O
authors.forename: Javier
authors.initials: J
authors.lastname: Torres
authors.forename: Martha
authors.initials: M
authors.lastname: Pérez-Rodríguez
authors.forename: Margarita
authors.initials: M
authors.lastname: Camorlinga-Ponce
authors.forename: L Flores
authors.initials: LF
authors.lastname: Luna
authors.forename: José M
authors.initials: JM
authors.lastname: Abdo-Francis
authors.forename: Eduardo
authors.initials: E
authors.lastname: Lazcano
authors.forename: Carmen
authors.initials: C
authors.lastname: Maldonado-Bernal