PMC

Representative major histocompatibility complex I (MHC-I) and RIG-I staining in serial sections of muscle biopsies. a MHC-I is expressed in the muscle fibers from a patient with dermatomyositis (DM) displaying perifascicular atrophy. b RIG-I is expressed in perifascicular areas in the sample from a patient with DM. c MHC-I is expressed in perifascicular atrophic areas in the sample from a patient with mixed connective tissue disease, whereas RIG-I is not expressed (d). Original magnification × 100