Monoclonal antibodies to human glomerular antigens.
Using cultured human fetal kidney cortical cells as antigen, two monoclonal antibodies (moAbs) against human glomeruli were produced. One of these moAbs, H-4, recognized the cell surface of glomerular epithelial cells, and the other, H-13, recognized the extracellular matrix present in the mesangial area. Both also reacted with liver, H-4 recognizing antigen present on the hepatocyte, and H-13 recognizing antigen distributed along the sinusoid. Species specificity for these moAbs was examined using mouse, rat, guinea pig and rabbit glomeruli, which revealed that H-4 reacted with rat glomerular epithelial cells and H-13 stained guinea pig glomerular mesangium. In the human fetal kidney, H-13 reacted with the mesangium, glomerular and tubular basement membrane and Bowman's capsule, and H-4 with the glomerular and tubular epithelial cells. Dot immunobinding assay of fibronectin purified from glomerular culture supernatant and plasma revealed that H-13 recognized both plasma and cellular fibronectin. Immunoblot analysis of 2.0 M guanidine HCl extract after dissociation in sodium dodecyl sulfate and electrophoresis demonstrated binding of H-4 to a 125 kd polypeptide. Immunoblot analysis of thermolysin-digested fibronectin exhibited binding of H-13 to 145 kd and 110 kd fragments, but not to 38 kd-29 kd fragments. In renal biopsy specimens from patients with membranous nephropathy. H-13 stained the glomerular basement membrane (GBM), but not the mesangium, whereas anti-fibronectin antisera stained both the GBM and the mesangium. In those from patients with minimal change nephrotic syndrome (MCNS), IgA glomerulonephritis (IgAGN) and membranoproliferative glomerulonephritis (MPGN), the staining pattern with H-13 was similar to that with polyclonal anti-fibronectin antisera. These results indicate that H-4 recognizes a 125 kd polypeptide constituent of the glomerular epithelial cell membrane and that H-13 recognizes the cell binding domain of fibronectin as well as revealing structural alterations in the mesangium and GBM.
D000818:Animals; D000911:Antibodies, Monoclonal; D000941:Antigens / Q000032:analysis*; D001485:Basement Membrane / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology; D004848:Epithelium / Q000276:immunology; D005109:Extracellular Matrix / Q000276:immunology; D005353:Fibronectins / Q000276:immunology*; D005920:Glomerular Mesangium / Q000276:immunology*; D005921:Glomerulonephritis / Q000276:immunology / Q000473:pathology; D005922:Glomerulonephritis, IGA / Q000276:immunology / Q000473:pathology; D006168:Guinea Pigs; D006801:Humans; D007118:Immunoassay; D007674:Kidney Diseases / Q000276:immunology / Q000473:pathology; D007678:Kidney Glomerulus / Q000276:immunology*; D009402:Nephrosis, Lipoid / Q000276:immunology / Q000473:pathology; D011817:Rabbits; D051381:Rats; D013045:Species Specificity
D000911:Antibodies, Monoclonal; D000941:Antigens; D005353:Fibronectins