Entactin-1 immunolabeling. Glomerular wall of the wild-type +/+ (A), entactin-1-null heterozygous (+/-) (B), and homozygous (-/-) (C) animals. Tissues from wild-type mice demonstrate intense labeling in the glomerular basement membrane (GBM) compared to those of entactin-1-null mice +/- (B) and -/- (C). L, capillary lumen; P, podocytes; US, urinary space.