This study aims to elucidate the relationship between Tregs and IL‐6R blockade in autoimmunity‐mediated renal disease based on a TCZ‐treated cohort of patients with anti‐neutrophil cytoplasmic antibody (ANCA)‐associated vasculitis (AAV) and in an experimental model of crescentic glomerulonephritis (cGN). The gene discussed is IL6R; the disease is crescentic glomerulonephritis.