A disease is said to be "rare" when it affects one person in 2,000, which represents three million people in France. Most rare diseases (80%) are genetic in origin ; the earlier they start in childhood, the more severe they can be. Rare pediatric diseases include autoimmune diseases (systemic lupus, juvenile dermatomyositis and juvenile idiopathic arthritis) and autoimmune diseases (interferonopathies, FMF, CAPS, TRAPS, and DADA2). Systemic autoimmune diseases are characterized by an inappropriate adaptive immune response (mediated by autoreactive T and/or B lymphocytes) with the production of autoantibodies directed against the constituents of the self (tolerance breakdown). Autoinflammatory diseases, unlike autoimmune diseases, correspond to an excess in the innate immune response (cytokines, macrophages, NK cells, granulocytes, etc.)..The precise pathophysiological mechanisms of these diseases have yet to be fully elucidated. Recent research has led to advances in the diagnosis and identification of monogenic forms of these diseases, particularly in early onset, familial, and syndromic forms. Nevertheless, the rarity of these diseases and limited availability of biological samples are major challenges that need to be overcome.
Thus, the aims of this study were as follows:
- The creation of a biological collection: primary cells (PBMC), DNA, RNA, lymphoblastic lines, and serum, which, through various research projects, will help identify genetic and immunological abnormalities in rare autoimmune and autoinflammatory diseases.