Figure 2From: Rainbow trout (Oncorhynchus mykiss) muscle satellite cells are targets of salmonid alphavirus infection Kinetics of sleeping disease lesion appearance in the skeletal muscle of experimentally infected rainbow trout through histopathology and immunohistochemistry studies. A Time course of clinical and histological signs. B Histological and immunohistochemical characterisation of skeletal muscle pathology following SDV infection. a First lesions were observed 18 days post-infection. They were characterized by focal myofiber necrosis (arrows). b The severity of myofiber necrosis increased until day 26; c at this time point, a positive immunolabelling of SDV E2 antigens was detected at the periphery of necrotic myofibers (arrowheads). d At day 54 post-infection, a diffuse regeneration of the skeletal muscle was observed, with infiltration of macrophages and activation/differentiation of satellite cells, e that can fuse to form new myofibers, displaying aligned central nuclei. f Fifty-seven days post-infection, skeletal muscle was regenerated but a high proportion of myofibers was atrophied.Back to article page