“…Antibody cross-reactivity between exogenous retroviruses and ERV3 peptides have been described ( Katsumata et al, 1999 ) and ERV3 is up-regulated by cytokines in endothelial cells ( Sasaki et al, 2009 ). Indeed, ERV3 has been suggested as an auto-antigen involved in different immune-pathologies ( Takeuchi et al, 1995 ; Li et al, 1996 ; de Parseval et al, 1999 ; Blank et al, 2009 ; Nelson et al, 2010 , 2014 ; Kowalczyk et al, 2012 ). Expression of ERV3 was found to be up-regulated in blood cells but down-regulated in skin biopsies from patients with morphea ( Li et al, 1996 ).…”