Clinical significance of interferon lambda-3 (IFNλ3)/interleukin 28B (IL28B) in systemic lupus erythematosus patients

Abstract

BackgroundInappropriate and excessive activation of type I interferon (IFN) system is a key feature of systemic lupus erythematosus (SLE), and its targeting has led to important achievements in the development of novel drugs for SLE. Aim of the workTo evaluate the serum levels of interferon lambda IFNλ3 (IL28B) in Egyptian patients with SLE and investigate its potential relation with different clinical and laboratory parameters. Patients and methodsThe study included 40 SLE patients and 40 controls. The SLE disease activity index (SLEDAI) was assessed. The measurement of serum levels of IFNλ3 was performed in all participants using enzyme linked immunosorbent assay (ELISA). ResultsThe mean age of the patients was 26.8 ± 7.8 years with disease duration 5.1 ± 4.5 years and they were 35 females and 5 males. The serum levels of IFNλ3 were significantly higher in SLE patients (9.7 ± 12.47 pg/mL) compared to the control (5.13 ± 1.63 pg/mL)(p = 0.02). Significant correlations were observed between serum IFNλ3 and serositis (r = 0.35,p = 0.03), C3 consumption (r −0.33, p = 0.04) and SLEDAI (r 0.34, p = 0.03). On multivariate regression analysis, serositis and SLEDAI (but not C3) were significant independent predictors of IFNλ3 levels (β = 0.08, p = 0.037 and β = 0.06, p = 0.014 respectively). ConclusionThe results support a possible role of IFNλ3/IL28B in the immunopathogenesis of SLE. The significant association of serum IFNλ3 with disease activity highlights the utility of IFNλ3 as a novel biomarker for monitoring disease activity and predicting severity in SLE. Further studies on IFNλ3 in SLE could be promising in the development of personalized therapy for lupus patients.