MPO-specific CD4+ T cells are present in patients with anti-MPO glomerulonephritis (GN) [47–49]; these can mediate glomerular injury directly as they recognise MPO released from neutrophils undergoing degranulation, apoptosis, and NETosis, inducing [50] delayed-type hypersensitivity through enhanced IFN-γ production. The gene discussed is MPO; the disease is ganglioneuroma.