Background The progression of rheumatoid arthritis (RA) is strongly associated with the immune mechanisms and substances affecting the immune system including chemokines and cytokines.

Objectives The aim of the study was to examine the relation among polymorphisms and serum levels of selected cytokines (IL-6, IL-13, IL-15), production of autoantibodies, and factors describing activity and progression of RA, such as DAS28 and Total Sharp score.

Methods A total of 144 RA patients according to the ACR classification criteria 1987, and 50 control subjects were recruited into the study. The measurements of serum levels of CRP, ACPA, and RFs, radiographs of both hands with calculation of Total Sharp score (TSS), DAS28, and serum levels of cytokines (IL-6, IL-13, IL-15) were obtained from all RA patients.

Results Significant difference in allele frequencies between RA patients and controls was observed for IL-15 -267C/T polymorphism. No significant association of IL-15 gene polymorphisms (367 G/A, 14035 A/T), IL-13 (-1112 C/T), and IL-6 with RA was found. Significant difference between RA patients and controls was observed for IL-15 -267C/T polymorphism in allele frequencies (p = 0.05). Higher prevalence of heterozygote variants of IL-15 14035 A/T and -267C/T polymorphisms in the RFs negative subgroup (IgG, IgA, IgM; p < 0.05) were observed. The frequency of the T allele of the IL-13 polymorphism C1112T was higher in subgroup with faster progression of the disease (TSS/month ≥ 0.1, p = 0.03).

Conclusions In conclusion, we present a correlation of IL-15 gen promoter polymorphisms with the rheumatoid factor subtypes (RF IgG, IgA, IgM) underlined by association with increased levels in circulation.

Disclosure of Interest None Declared