Étude des polymorphismes des gènes de l’interleukine-1 et de l’antagoniste du récepteur de l’interleukine-1 chez des patients atteints de polyarthrite rhumatoïde

Objectives

One of the most important pro-inflammatory cytokines in the pathophysiology of rheumatoid arthritis (RA) is interleukin 1 (IL-1). The purpose of this study is to evaluate the association between IL-1B (-511), IL-1 (+3953), IL-1 RN variable number of tandem repeat (VNTR) polymorphisms and the occurrence in Algerian patients with rheumatoid arthritis. We also analyze their correlations with clinical and biological phenotypes.

Patients and methods

One hundred and forty-seven patients with RA (119 women, 28 men) and 127 controls (70 women, 57 men) were included in the study. The analysis of two polymorphisms of IL-1B-511 and IL-1B+3953 was done by PCR-RFLP. Analysis of IL1-RN VNTR polymorphism was performed by PCR.

Results

No significant difference in genotype, allelic and haplotype distribution at the three polymorphisms was observed between RA patients and controls. However, the genotype (T/T) polymorphism of IL-1B-511 is more frequent in the group of patients with positive ACPA compared with negative ACPA group (Pc = 0.01, OR = 4.65). Moreover, we noted that the haplotype (IL-1RN* 1/IL-1B-511T/IL-1B+3953C) was more frequent (Pc = 0.03, OR = 2.05) in the positive ACPA group.

Conclusion

The association between the allele 1 of IL-1 RN VNTR, T allele of IL1B-511 and C allele of IL1-B +3953 polymorphisms seems to predispose to the synthesis of ACPA and therefore to the occurrence of ACPA positive RA. Further studies with a larger number of patients are needed to define the real role of IL-1 in the susceptibility to or severity of RA.