[Systemic lupus erythematosus: from pathophysiology to treatment].

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with multiorgan involvement characterized by an immune response against nuclear components. SLE patients experience a waxing and waning disease course and exhibit a wide array of clinical manifestations, reflecting the systemic nature of the disease. Environmental triggers such as viruses are likely to act in the context of susceptibility genes, including genes involved in antigen/immune complex clearance, lymphoid signalling, or apoptosis, among several others, explaining why the pathogenesis of this disease remains largely uncovered. The abnormal activation of the innate immunity is central to SLE physiopathology. Dendritic cells activation and unabated secretion of IFN-alpha are the key features of the disease through their involvement in the capture and the presentation of nuclear material to the autoreactive adaptive arm (T and B lymphocytes) leading to the subsequent production of anti-nuclear autoantibodies. In this line, numerous studies have demonstrated the prominent role of immune complexes deposition throughout the body which directly can induce inflammation and tissue damage. However, animal models and recent human studies support the concept that other effector pathways including cytotoxic T-lymphocytes could be involved in SLE pathogenesis through their ability to migrate and/or target specifically different tissues. The aim of this review is not to provide a comprehensive review of the SLE pathophysiology but rather to give an overview of the immunological abnormalities associated to SLE. The treatments that are currently used or that are in development to fight against abnormal immune response in SLE will be detailed. The genetics of SLE is not the scope of this review.