Some research suggests that these changes in FSGS are a continuation from another nephrotic syndrome called minimal change disease which is also characterized by podocyte injury.
Alright so on histology, there'll be segmental sclerosis and hyalinosis of the glomeruli, and under electron microscope, there's effacement of the foot processes of the podocytes.
What is known, though, is that the podocytes, which are the cells that have these long tentacle-like projections, called foot processes, that wrap around the capillaries in the glomeruli, are damaged.
Whether they bind directly to the GBM, or come from somewhere else, these immune complexes are called subepithelial deposits because they're sandwiched right between the epithelial cells or podocytes, and the GBM.