We have composed a logical argument to substantiate that autoimmunity is actively involved in the pathogenesis of DA apoptosis in PD through several proteins, including α-synuclein, DJ-1, PINK1, and parkin [6–8], as well as autoimmune cells, such as B cells and plasma cells, conventional CD4+ and CD8+ T cells, microglial cell, dendritic cell, and NK cell [9, 10]. The gene discussed is CD8A; the disease is Parkinson disease.