In contrast to the anti-CD25 mAb treatment, with mild autoimmune manifestations, germline FoxP3 mutations or general depletion of Treg performed in conditional FoxP3 mutants leads to lymphadenopathy, extensive T-cell activation and severe autoimmune lymphoproliferative disease in neonates and adults [35], [39]. The gene discussed is FOXP3; the disease is Lymphadenopathy.