However, there are additional tolerogenic mechanisms, including the apoptotic deletion of immune effector cells by death-inducing ligands, the toleration of tumour-reactive T cells by immunosuppressive cytokines, such as TGF-β, the suppression of immune-reactive T cells by Tregs, and polarization by antigen-cross-presenting cells, such as DCs36, 37. The gene discussed is TGFB1; the disease is neoplasm.