title: HLA-G 14-bp Ins/Ins Genotype in Patients Harbouring Helicobacter pylori Infection: A Potential Risk Factor?
abstract: H. pylori is a potent pathogen due to its capacity to successfully evade host defence mechanisms. Despite inducing immune responses in infected individuals, sometimes these responses fail to clear the infection and the bacterium establishes a persistent infection leading to chronic inflammation. In this context, we hypothesized that human leucocyte antigen G (HLA-G), a non-classical major histocompatibility complex molecule that has the ability to regulate immune responses both in physiological and in pathological conditions, may play an important role in promoting tolerance and helping H. pylori to subvert host defence and consequently establish a chronic infection. Therefore, we evaluated the expression of HLA-G 14-bp Ins/Del polymorphism in patients harbouring H. pylori infection, as well as their relationship with histological and demographic variables, to gain a better understanding of the actual role of HLA-G and its genetic polymorphisms in bacterial infection. Sixty-eight patients with clinical symptoms suggestive of H. pylori infection were enrolled to assess HLA-G 14-bp Ins/Del polymorphism allele and genotype frequencies. After adjustment for covariates (age and gender), the odds of having the genotype Ins/Ins, compared to Del/Del, were 3.77 times greater among HP+ cases than among controls. These findings suggest that the 14-bp Ins/Ins genotype, already associated with inflammatory and autoimmune diseases as well as some viral and parasitic infections, could confer a greater risk of developing H. pylori infection.
authors.affiliation: Programa de Pós-graduação em Ciências da Saúde, Centro de Ciências da Saúde. Universidade Federal do Rio Grande do Norte, Natal, Brasil.
authors.forename: J
authors.initials: J
authors.lastname: Genre
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde. Faculdade de Farmácia, Universidade Federal do Rio Grande do Norte, Natal, Brasil.
authors.forename: F P Santos
authors.initials: FP
authors.lastname: Reginaldo
authors.affiliation: Departamento de Estatística, Instituto de Ciências Exatas, Universidade de Brasília, Brasília, Brasil.
authors.forename: J Marco de Leon
authors.initials: JM
authors.lastname: Andrade
authors.affiliation: Departamento de Patologia, Centro de Ciências da Saúde. Universidade Federal do Rio Grande do Norte, Natal, Brasil.
authors.forename: F P
authors.initials: FP
authors.lastname: Lima
authors.affiliation: Hospital universitário Onofre Lopes. Universidade Federal do Rio Grande do Norte, Natal, Brasil.
authors.forename: A V Coutinho
authors.initials: AV
authors.lastname: da Camara
authors.affiliation: Departamento de Medicina Clínica, Faculdade de Medicina de Ribeirão Preto. Universidade de São Paulo, Ribeirão Preto, Brasil.
authors.forename: E A
authors.initials: EA
authors.lastname: Donadi
authors.affiliation: Departamento de Análises Clínicas, Centro de Ciências da Saúde. Faculdade de Farmácia, Universidade Federal do Rio Grande do Norte, Natal, Brasil.|Programa de Pós-graduação em Ciências Farmacêuticas, Centro de Ciências da Saúde. Universidade Federal do Rio Grande do Norte, Natal, Brasil.
authors.forename: J C
authors.initials: JC
authors.lastname: Crispim
mesh_terms: D000328:Adult; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D059951:HLA-G Antigens / Q000235:genetics*; D016481:Helicobacter Infections / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012307:Risk Factors
chemical_list: D059951:HLA-G Antigens