Figure 4
Electron microscopic analysis of affected glomeruli (a, c-f, h), and tubules (g) on day 4 (a, c-g) and week 5 (h) after injection of pCAG/DT-A/FuGENEâ„¢6 complex. In the affected glomeruli (a), severe matrix expansion with numerous electron-dense deposits was detected in the mesangial matrix. The capillary lumen of endothelial cells was deformed, probably due to proliferation of active mesangial cells. Degeneration of mesangial cells was sometimes observed [indicated by an arrow in (a)]. In contrast, the control glomeruli derived from mock injection of PBS(-) on day 4 (b) exhibited normal appearance. Notably, formation of focal deposits in glomerular basement membrane was often remarkable [indicated by arrows in (c-f)]. The initial, small deposits of glomerular basement membrane are shown by arrowheads in (d) and (e). Incorporation of lipids, probably DNA/lipid complexes that had been re-uptaken by renal tubules, was noted in the cytoplasm of renal tubules [indicated by arrows in (g)]. On week 5, nearly normal glomerular structure was observed (h).