Increased frequency of ICOS+ or ICOShigh cTFH cells standing for an “activated” phenotype has been found in patients with autoimmunity such as RA [72], SS [73], myasthenia gravis (MG) [74], SLE [75], autoimmune thyroid diseases [76], and all autoimmune pathologies partially caused by autoantibodies [1]. Here, ICOS is linked to systemic lupus erythematosus.