Interestingly, other examples of ADAP regulating the surface expression of membrane molecules on immune cells include promoting PD-1 surface expression in cytotoxic T lymphocytes via the transcription factor NFATc1 during antitumor immunity (41) and inhibiting FcγRI/IV surface expression on macrophages via STAT1 in immune thrombocytopenia (15). The gene discussed is STAT1; the disease is autoimmune thrombocytopenic purpura.