Interleukin-1 receptor antagonist autoantibodies in Still’s disease: Mechanistic insights and laboratory testing

Core Tip

Core Tip: Still’s disease is a rare, severe systemic inflammatory disorder characterized by elevated levels of neutralizing interleukin-1 receptor antagonist autoantibodies. Their induction is thought to result from a combination of host-related factors, such as human leukocyte antigen class II alleles, and interleukin-1 receptor antagonist intrinsic factors, including hyperphosphorylation. Despite frequent detection of these antibodies using immunoassays and functional cell-based assays, the lack of assay standardization limits their clinical utility. At present, their presence is best regarded as a marker of underlying immune dysregulation rather than a direct pathogenic driver.