Figure 5

Pathological changes of the muscle after electroporation. The photographs show representative histological sections of the gastrocnemius of C57BL/6 mice. Magnification ×100. A1-3: different sections at 7 days after plasmid electroporation (200 v / cm). The sections were performed in the middle of the white lesion seen macroscopically. They reveal a severe rhabdomyolysis and infiltration by mast cells, eosinophils and mononuclear cells. At the periphery of the lesion, the damages were less severe, the myocytes were not completely necrotic but were pale. In the part of the muscle that was macroscopically normal, there was only a diffuse mild to moderate inflammatory infiltrate. The black arrows indicate necrosis and white arrows indicate inflammatory infiltrate. B: muscle section of a healthy mouse.