Glomerular endothelial cells and podocytes jointly synthesize laminin-1 and -11 chains

During the glomerular basement membrane assembly, laminin-111 is initially expressed in vascular clefts of comma- ann S-shaped bodies and is eventually replaced by laminin-521 which persists into maturation. Post-fixation immunoelectron microscopy of developing mouse and 2-3 days old mice kidney was performed and showed Intracellular labeling for laminin-111 and laminin-521 in developing glomerular endothelial cells and podocytes. In early capillary loop stage, GBMs laminin-111 was absent but the expression of a5 was strong (developmental switch). The results show that both endothelial cells and podocytes synthesize laminin but the highest level of laminin synthesis by endothelial cells.