Impaired activation-induced T-cell death; lymphoproliferative syndrome; autoimmunity Adachi et al. (1996); Accumulation of autoreactive B cells in T cell-rich zones; production of autoantibodies Rieux-Laucat et al. (1995); Resistant to suppression by high doses of antigen and to apoptosis in mature CD4 T cells Singer and Abbas (1994). Here, CD4 is linked to Autoimmunity.