HMGB1 and polymyositis: For instance, increased levels of S-100B (one RAGE ligand) and RAGE are observed in experimental animal models of myasthenia gravis [26, 27]; and overexpression of HMGB1, CML(both RAGE ligands), and RAGE was found in the muscle fibers of polymyositis and dermatomyositis patients [28, 29].