The role of cytokines in the pathogenesis and treatment of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that is characterized by a defect in immune tolerance and exacerbated by both the innate and adaptive arms of the immune response. SLE-associated immune hyperactivity can be detected systemically as elevations in levels of cytokines along with their upregulated receptors expressed by hematopoietic cells. Importantly, increased levels of cytokines and their receptors can be observed in target organs, and it is clear that they have important roles in disease pathogenesis. Recent therapeutic strategies have focused on proximal cytokines, such as interferon-α, interleukin (IL)-1, IL-6, and tumor necrosis factor as a result of the efficacious use of biologic agents for intervention in rheumatoid arthritis and other autoimmune diseases. Despite the recent advances in understanding the cytokine networks involved in autoimmune diseases and more specifically in SLE, the diagnosis and prognosis of lupus remain a challenge. Lupus is heterogeneous and unpredictable; moreover, the frequency and severity of flares can be difficult to determine and treat. A better understanding of the regulation of expression of key cytokines and their receptors can likely provide important clues to the pathogenic mechanisms underlying specific forms of SLE, and pave the way toward more effective therapeutics.