Background and Aims

Proinflammatory cytokines play critical role in the pathophisology of rheumatoid arthritis (RA). Recent studies concerning IL-8 support its role in ACPA-mediated osteoclast activation as a mechanism of arthralgia and bone loss, but the functional involvement of this cytokine are still uninvestigated. This analysis aimed to determine the association of IL-8 cytokine levels with clinical variables in patients with RA.

Methods

63 patients with RA and 25 patients in control group were included in this study. The cytokines levels in serum were evaluated by the ProcartaPlex immunoassays kits (eBioscience, Affymetrix) on the Luminex xMAP system according to manufacturer’s instruction.

Results

IL-8 was elevated in RA patient group (p<0.0001). We found differences between control group and RA activity groups according to Disease Activity Score in 28 joints (Figure1.).

Figure 1. IL-8 concentration in RA and healthy control. Blue line connects medians.

IL-8 was also positively correlated with C-reaction protein (r=0,43), erythrocyte sedimentation rate (r=0,4), level of autoantibodies (RF: r=0,54; ACPA: r=0,51). Furthermore there was correlation between IL-8 and number of swollen (r=0.38) and painfull joints (r=0.33).

Conclusions

Circulating IL-8 is correlated with disease activity and ACPA, therefore may impact the pathogenesis and progression of RA and may be the point of further investigations.