Checkpoint receptors, such as B and T lymphocyte attenuator (Btla), are widely expressed in lymphocyte and myeloid cells, where they function to regulate innate and adaptive immune responses and prevent the development of autoimmune disease (Schildberg et al., 2016; Ward-Kavanagh et al., 2016; Zhang and Vignali, 2016). The gene discussed is BTLA; the disease is autoimmune disease.