Immunochemical Studies on a Nephritis-Associated Ubiquitous Tissue Antigen

Abstract

A ubiquitous tissue antigen (UTA), associated with chronic renal diseases was partially purified and characterized. The antigen was extracted by solubihzation in 0.5% sodium deoxycholate (DOC) of various organs of human and animal origin. UTA was soluble in ammonium sulfate at 50% concentration and precipitable in 71% ethanol. Considerable purification of UTA was achieved by fractional ammunium sulfate precipitation, zone electrophoresis and gel filtration. Gel filtration on Sephadex G-200 and velocity gradient centrifugation through 10–40% sucrose gradients suggested that the main antigenic component is a macromolecule, although aggregability of DOC-extracted proteins upon removal of the solubilizer prevented more accurate determinations. UTA appeared to be a heat-stable glycoprotein which did not contain lipids detectable by Sudan black B staining. The yield of purest UTA preparations, which did not contain components of homologous serum as tested by double diffusion gel precipitation or immunoelectrophoresis, was 0.1–0.2 mg/100 g of starting tissue. Immunization of rabbits with homologous UTA-containing preparations resulted in anti-UTA antibody formation.