To determine whether the low expression of GLUT2 on PB-IPC was specific for T1D, we examined the levels of GLUT2 expression in patients with other autoimmune diseases (e.g., alopecia areata, Sjogren’s syndrome, and rheumatoid arthritis) and inflammation-associated neuronal degenerative disease such as Parkinson’s diseases (n = 3). The gene discussed is SLC2A2; the disease is rheumatoid arthritis.