A new lymphocyte surface protein present in normal urine. I. Isolation and physicochemical properties

A lymphocyte surface glycoprotein designated urinary acidic antigen (UA) has been isolated from normal urine by a combination of preparative isoelectric focusing and ammonium sulfate precipitation. It has an m.w. of 14,000 to 17,500 daltons, and is approximately 60% carbohydrate and 40% amino acid in content. The protein exhibited the following physical properties: S20,omega = 1.24; v = 0.693 ml/g; E1%1 cm, 278 nm = 2.08; and pI-2.5. It appears to be unrelated to beta 2-microglobulin, protein HC, urinary proteose, microglobulin, or any previously described normal urine or human serum protein.