title: Anti-Thy-1 monoclonal antibody with specific reactivity with vascular endothelial cells in rat glomeruli.
abstract: Inoculation with anti-Thy-1 antibodies (Abs) in rats induces glomerulonephritis resembling human mesangiolytic and/or mesangioproliferative diseases. Some anti-Thy-1 monoclonal Abs (mAbs) react with both mesangial and glomerular endothelial cells, whereas others react solely with mesangial cells in rat kidney. These findings suggest that the rat Thy-1 molecule possesses at least 2 variant forms, including a mesangial and a vascular endothelial isoform. However, anti-Thy-1 mAbs with specific reactivity with glomerular endothelial cells have not been available. We describe here a unique anti-rat Thy-1 mAb, TM78-8. The epitope for TM78-8 is closely related, but not identical, to that for OX-7, a commercially available anti-rat Thy-1 mAb. Immunoblotting, immunohistochemistry and immunoelectron microscopy confirm that TM78-8 reacts exclusively with Thy-1 antigens on the surface of vascular endothelial cells in rat glomeruli. TM78-8 may be a suitable marker for rat glomerular endothelial cells as well as for the vascular endothelial isoform of the rat Thy-1 molecule. Intravenous injection of TM78-8 did not induce glomerulonephritis in rats, whereas OX-7 did, indicating that TM78-8 is not nephritogenic. This finding also corresponds with the current consensus that Thy-1 antigens expressed on mesangial cells play an essential role in the development of Thy-1 nephritis.
authors.affiliation: Department of Pathology and Pathophysiology, Hokkaido University Graduate School of Medicine, Sapporo, Japan. aishizu@med.hokudai.ac.jp
authors.forename: A
authors.initials: A
authors.lastname: Ishizu
authors.forename: Y
authors.initials: Y
authors.lastname: Ogawa
authors.forename: H
authors.initials: H
authors.lastname: Ishikura
authors.forename: T
authors.initials: T
authors.lastname: Yoshiki
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D004730:Endothelium, Vascular / Q000166:cytology / Q000276:immunology*; D005434:Flow Cytometry; D005921:Glomerulonephritis / Q000276:immunology; D006801:Humans; D007678:Kidney Glomerulus / Q000098:blood supply*; D011507:Proteinuria / Q000139:chemically induced / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D018800:Thy-1 Antigens / Q000276:immunology* / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D018800:Thy-1 Antigens