Figure 3. Immunolocalization of a-smooth muscle actin (a-SM-actin) in the renal cortex from a control individual (A) and from a patient with focal segmental glomerulosclerosis (B) using an anti-a-SM-actin antibody. Note in A that the reaction was observed only in vascular muscle cells (score 0) and in B there is strong and diffuse staining involving a majority of glomeruli and the renal cortex (score 4) (original magnification: 250X).