Human corticosteroid binding globulin is secreted by a hepatoma-derived cell line

We used a sensitive radioimmunoassay for corticosteroid-binding-globulin (CBG) to demonstrate that a human hepatoma-derived cell line secretes a protein which: (a) the radioimmunoassay cannot distinguish from CBG; (b) has the same Stokes' radius as CBG; (c) is absorbed by a steroid affinity column which is specific for CBG.