Monoclonal antibodies that bind the renal Na/sup +//glucose symport system. 1. Identification

Journal Article · Tue Sep 08 04:00:00 EDT 1987 · Biochemistry; (United States)

OSTI ID:5879347

Wu, J S.R.; Lever, J E

Phlorizin is a specific, high-affinity ligand that binds the active site of the Na/sup +//glucose symporter by a Na/sup +/-dependent mechanism but is not itself transported across the membrane. The authors have isolated a panel of monoclonal antibodies that influence high-affinity, Na/sup +/-dependent phlorizin binding to pig renal brush border membranes. Antibodies were derived after immunization of mice either with highly purified renal brush border membranes or with apical membranes purified from LLC-PK/sub 1/, a cell line of pig renal proximal tubule origin. Antibody 11A3D6, an IgG/sub 2b/, reproducibly stimulated Na/sup +/-dependent phlorizin binding whereas antibody 18H10B12, an IgM, strongly inhibited specific binding. These effects were maximal after 30-min incubation and exhibited saturation at increased antibody concentrations. Antibodies did not affect Na/sup +/-dependent sugar uptake in vesicles but significantly prevented transport inhibition by bound phlorizin. Antibodies recognized a 75-kDa antigen identified by Western blot analysis of brush border membranes, and a 75-kDa membrane protein could be immunoprecipitated by 18H10B12. These properties, provide compelling evidence that the 75-kDa antigen recognized by these antibodies is a component of the renal Na/sup +//glucose symporter.

• Research Organization: Univ. of Texas Medical School, Houston
• OSTI ID: 5879347
• Journal Information: Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 26:18; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALDEHYDES
ALKALI METAL COMPOUNDS
ANIMALS
ANTIBODIES
ANTIGENS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BODY
CARBOHYDRATES
CARBON 14 COMPOUNDS
DAYS LIVING RADIOISOTOPES
DOMESTIC ANIMALS
ELECTRON CAPTURE RADIOISOTOPES
ELECTROPHORESIS
GLUCOSE
GLYCOSIDES
HEXOSES
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KETONES
KIDNEYS
LABELLED COMPOUNDS
LIGANDS
MAMMALS
MEMBRANE TRANSPORT
MOLECULAR STRUCTURE
MONOCLONAL ANTIBODIES
MONOSACCHARIDES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PHLORIZIN
RADIOISOTOPES
SACCHARIDES
SODIUM COMPOUNDS
SWINE
TRITIUM COMPOUNDS
VERTEBRATES