TGM2 and type 1 diabetes mellitus: Interestingly, tissue transglutaminase (TTg), one of the major players in CeD autoimmunity, can modify PTEN, a phosphatase of the PTP family, also increasing the activity binding of the auto-antibodies (IA-2; anti-islet antibodies) participating in the autoimmune response in type 1 diabetes [89].