It has also been reported that TRE-H-2Kb x mck-Tta (HT) mice with conditional overexpression of H-2Kb in muscle presented an upregulation of ER stress markers and molecular targets of UPR such as BiP/GRP78, CRT, CNX, and ATF6, in addition to pathologic features of non-specific myopathy with variations in myofiber size, numerous centronucleated fibers, and endomysial fibrosis (139). This evidence concerns the gene HSPA5 and fibrosis.