TGM2 and neurodegenerative disease: Increased levels of TG2 are observed in several human pathologies including neurodegenerative diseases such as Alzheimer’s, Huntington’s, and Parkinson’s diseases, as well as in chronic inflammatory conditions (Taylor et al., 2003; Malorni et al., 2008; Iismaa et al., 2009; Mastrobernardino and Piacentini, 2010).