Interferon-Induced Protein-10 and Plasma Interleukin-26 in Systemic Lupus Erythematosus

Background: Systemic lupus erythematosus is a chronic, immune-mediated, multifactorial illness that affects multiple systems. One cytokine that has a role in the pathophysiology of a number of inflammatory diseases is interferon-induced protein 10 (IP-10). The newest member of the IL-20 cytokine subfamily, interleukin-26 (IL-26), is a novel mediator of inflammation that is overexpressed in activated immune cells. Objective: The aim of this work was to assess the plasma levels of IL-26 and IP-10 expression in peripheral blood mononuclear cells (PBMCs) in lupus patients and healthy controls, as well as establishing a relationship between these levels and lupus activity. Methodology: Forty-five lupus patients with forty-five matched controls were included. The real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate IP-10 expression levels in PBMCs, while plasma IL-26 levels were measured using the enzyme-linked immunosorbent assay (ELISA). Results: Compared to the control group, lupus patients had significantly higher levels of plasma IL-26 and PBMC expression of IP-10 (P-value < 0.001). The levels of IP-10 expression and lupus activity were shown to be significantly positively correlated (r = 0.361, P-value < 0.015). Furthermore, a significant relationship between lupus activity and IL-26 levels was observed (r = 0.573, P-value < 0.001). The levels of IL-26 and IP-10, meanwhile, showed a strong positive correlation (r = 0.619, P < 0.001). Conclusion: IP-10 and IL-26 might be useful biomarkers for lupus diagnosis and prognosis, as well as promising therapeutic targets.