Elevated levels of serum sCXCL16 in systemic lupus erythematosus; potential involvement in cutaneous and renal manifestations

The aim of this study was to investigate the levels and clinical significance of serum soluble chemokine (C-X-C motif) ligand 16 (sCXCL16) in patients with systemic lupus erythematosus (SLE), as well as the sCXCL16 molecule's associations with disease activity and organ damage. Thirty-five patients with SLE, 16 patients with rheumatoid arthritis (RA), and 15 healthy controls were included in this study. The demographic and clinical features of the patients were recorded. The serum levels of sCXCL16 were determined. Disease activity was assessed using the SLE Disease Activity Index (SLEDAI), and organ damage was evaluated with the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index (SDI). The serum levels of sCXCL16 in the patients with SLE were higher than those in the patients with RA (P = 0.002) or healthy controls (P < 0.0001). The levels in the patients with active SLE were higher than those in the disease inactive patients (P = 0.008). Positive correlations were identified between serum sCXCL16 concentrations and both SLEDAI (r = 0.564; P < 0.0001) and SDI scores (r = 0.396; P = 0.018). Both SLEDAI (P = 0.021) and serum levels of CXCL16 (P = 0.023) decreased after conventional treatment in 12 initial onset cases of SLE patients. Elevated serum sCXCL16 levels were discovered in the SLE patients with cutaneous (P = 0.006) and renal involvement (P = 0.032). Soluble CXCL16 may become a useful serological marker of disease activity and skin and renal involvement in SLE patients; thus, it may be used for evaluation of therapeutic interventions.