“…However, the presentation of intracellular citrullinated proteins in the synovium is specific for RA ( Baeten et al, 2001 ), and is colocalized with PADI2 ( De Rycke, 2005 ). Numerous well-known or suspected intracellular substrates of PADI2 and PADI4 exist, such as vimentin ( Asaga et al, 1998 ; Vossenaar et al, 2004b ), histones ( Nakashima et al, 2002 ), nucleophosmin/B23 ( Hagiwara et al, 2002 ), the F-actin capping protein alpha 1 subunit, cathepsin D, beta-actin ( Matsuo et al, 2006 ), aldolase, alpha-enolase, phosphoglyce-rate kinase 1, calreticulin, the 60-kDa heat shock protein, far upstream element-binding proteins 1 and 2 ( Goëb et al, 2009 ), glucose-6-phosphate isomerase ( Umeda et al, 2013 ), and IKKγ ( Lee et al, 2010 ). Among these, vimentin is the major citrullinated protein in human monocytic leukemia THP-1 cells during macrophage differentiation ( Hojo-Nakashima et al, 2009 ).…”