First evidence for a role of citrullinated GRP78 in human T1D, came from the discovery of a CD4+ T-cell clone, isolated from an islet outgrowth of a deceased T1D patient, which recognized citrullinated GRP78 epitope 292-305 (citrullinated at position 297) (17). This evidence concerns the gene HSPA5 and type 1 diabetes mellitus.