[Pathophysiological advances underlying the biotherapeutic revolution in inflammatory rheumatism]

Major advances have been made in the pathogenesis of rheumatoid arthritis, spondyloarthritis and connective tissue diseases, leading to new biotherapies. In rheumatoid arthritis, the discovery of anti-citrulline antibodies (ACPA, anti-citrullinatedpeptide antibodies), whose specificity is between 95% and 98% and may be present before symptom onset, allowed early diagnosis and provided new pathological insights. Studies of the role of cytokines, B cells and co-stimulation of T cells revealed novel therapeutic targets. TNF inhibitors are effective in spondyloarthritis. In lupusandSjigren'ssyndrome, genes stimulatedby IFNtypel are hyper-expressed, along with BAFF (or BLyS), a B lymphocyte-activating cytokine.