Estudo da frequência dos alelos de HLA-DRB1 em pacientes brasileiros com artrite reumatoide

• Autor(a) principal: Usnayo, Magali Justina Gómez
• Data de Publicação: 2011
• Outros Autores: Andrade, Luiz Eduardo Coelho [UNIFESP], Alarcon, Renata Trigueirinho [UNIFESP], Oliveira, Juliana Cardoso, Silva, Gustavo Milson Fabrício, Bendet, Izidro, Burlingame, Rufus, Porto, Luis Cristóvão, Pinheiro, Geraldo da Rocha Castelar
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1590/S0482-50042011000500007; http://repositorio.unifesp.br/handle/11600/6679
• topic: HLA-DRB1; shared epitope; rheumatoid arthritis; genetic polymorphism; immunogenetics; HLA-DRB1; epítopo compartilhado; artrite reumatoide; polimorfismo gênico; imunogenética

The HLA-DRB1 alleles encoding an amino acid sequence (QKRAA/QRRAA/RRRAA) at position 70 74 of the third hypervariable region of the β1 chain of the HLA-DRB1 gene, called shared epitope (SE), are associated with increased susceptibility to and severity of rheumatoid arthritis (RA) in different populations. OBJECTIVE: To determine the frequency of HLA-DRB1 alleles in Brazilian patients with RA and their association with rheumatoid factor (RF) and anti-citrullinated peptide antibodies (ACPA). METHODS: Four hundred and twelve patients with RA (ACR 1987) and 215 controls were included. HLA-DRB1 typing was performed by use of polymerase chain reaction (PCR) with specific primers and hybridization with sequence-specific oligonucleotide probe (SSOP). ACPA was measured by use of the ELISA technique and RF by nephelometry. The statistical analysis comprised the chi-square and Student t tests and logistic regression. RESULTS: HLA-DRB1*04:01, *04:04, *04:05 alleles were associated with RA (P < 0.05); despite the wide confidence interval, it is worth noting the association between the DRB1*09:01 allele and RA (P < 0.05). HLA-DRB1 SE+ alleles were observed in 62.8% of the patients and in 31.1% of controls (OR 3.62; P < 0.001) and were associated with ACPA (OR 2.03; P < 0.001). DRB1-DERAA alleles showed a protective effect against RA (OR 0.42; P < 0.001). CONCLUSION: In a sample of Brazilian patients with RA, most of whom of mixed heritage, HLA-DRB1 SE+ alleles were associated with susceptibility to disease and presence of ACPA.