Clinical characteristics and frequency of TLR4 polymorphisms in Brazilian patients with ankylosing spondylitis.
Innate immunity is involved in the physiopathology of ankylosing spondylitis (AS), with the participation of Gram-negative bacteria, modulation of human leukocyte antigen (HLA) B27 and the involvement of pattern recognition receptors, such as Toll-like receptors (TLRs). The aim of this study was to investigate the clinical characteristics and frequency of TLR4 polymorphisms (Asp299Gly and Thr 399Ile) in a cohort of Brazilian patients with AS.



A cross-sectional study was carried out involving 200 patients with a diagnosis of AS and a healthy control group of 200 individuals. Disease activity, severity and functional capacity were measured. The study of TLR4 polymorphisms was performed using the restriction fragment length polymorphism method. HLA-B27 was analyzed by conventional polymerase chain reaction. The IBM SPSS Statistics 20 program was used for the statistical analysis, with p-values less than 0.05 considered significant.



Mean age and disease duration were 43.1±12.7 and 16.6±9.2 years, respectively. The sample was predominantly male (71%) and non-Caucasian (52%). A total of 66% of the group of patients were positive for HLA-B27. The sample of patients was characterized by moderate functional impairment and a high degree of disease activity. No significant association was found between the two TLR4 polymorphisms and susceptibility to AS.



TLR4 polymorphisms 399 and 299 were not more frequent in patients with AS in comparison to the health controls and none of the clinical variables were associated with these polymorphisms.
Divisão de Reumatologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Natalia Pereira
NP
Machado
Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Eliana
E
Nogueira
Divisão de Reumatologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Karen
K
Oseki
Divisão de Reumatologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Pâmela Carolina Cruz
PC
Ebbing
Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Clarice Silvia Taemi
CS
Origassa
Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Tatiane
T
Mohovic
Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil.
Niels Olsen Saraiva
NO
Câmara
Divisão de Reumatologia, Departamento de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil. Electronic address: mpinheiro@uol.com.br.
Marcelo de Medeiros
MM
Pinheiro
D000328:Adult; D001938:Brazil; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D015796:HLA-B27 Antigen / Q000235:genetics*; D006801:Humans; D008297:Male; D012150:Polymorphism, Restriction Fragment Length / Q000235:genetics*; D013167:Spondylitis, Ankylosing / Q000235:genetics*; D051197:Toll-Like Receptor 4 / Q000235:genetics*
D015796:HLA-B27 Antigen; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4
Ankylosing spondylitis; Espondilite anquilosante; HLA-B27; Polimorfismos em TLR-4; TLR-4 polymorphisms