Intracellular auto-antigens include glutamic acid decarboxylase GAD65/67 (diabetes mellitus and various CNS disorders including SPS [63,64]), double-stranded DNA (SLE), intraneuronal antigens CDR2, SOX1 and PNMA1 (often arising during paraneoplastic neurological disorders, reviewed in [65]) and TRIM21 itself (Sjögren’s syndrome and SLE; usually referred to as anti-SSA or anti-Ro52). This evidence concerns the gene PNMA1 and systemic lupus erythematosus.