Baseline serum levels of interleukin-6 (IL-6) and interleukin-17 (IL-17) can be used as biomarkers for disease activity and predictors of lupus nephritis remission in patients with systemic lupus erythematosus (SLE), according to data published in Cytokine.

To determine the role of IL-6 and IL-17 in the pathogenesis of SLE, Sahar M. Abdel Galil, MD, Rheumatology and Rehabilitation Department, Faculty of Medicine at Zagazig University in Egypt and Faculty of Medicine at Umm Al-Qura University in Saudi Arabia, and colleagues conducted a study of 72 female patients with SLE, age-matched with 70 patients without SLE serving as a control group.

SLE activity was assessed in all patients using the SLE Disease Activity Index (SLEDAI-2k). Plasma levels of both IL-6 and IL-17 were measured using the enzyme-linked immunosorbent assay; plasma levels were correlated with both SLEDAI-2k and clinical disease manifestation.

For a period of 1 year, patients were assessed every 2 months; at each visit, researchers reviewed SLEDAI-2k score, complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), 24-hour urine protein, and kidney function; anti-double-stranded DNA antibody (anti-dsDNA) titer was also obtained.

“SLE patients were found to have significantly higher levels of IL-17 and IL-6 (P < .001 each) in relation to normal subjects,” wrote Dr. Abdel Galil. “Elevated serum levels of both cytokines were associated with active lupus nephritis and anemia, and were positively correlated with SLEDAI-2k scores (P = .025 for IL-17 and P < .001 for IL-6).”

Researchers also identified a significant positive correlation between concentration of serum IL-6 and IL-17 and both disease activity (r = 0.497, P = .005) and periods of remission (r = 0.662, P < .001).

“In conjunction with their major role in pathogenesis of SLE, baseline serum levels of IL-6 and IL-17 can be used as sensitive biomarkers for disease activity, as well as predictors of remission of lupus nephritis,” wrote Dr Abdel Galil.

Reference

Abdel Galil SM, Ezzeldin N, El-Boshy ME. The role of serum IL-17 and IL-6 as biomarkers of disease activity and predictors of remission in patients with lupus nephritis. Cytokine. 2015. doi: 10.1016/j.cyto.2015.05.007