Characterization of an antigen defined by monoclonal antibody KMO1

Abstract

We have isolated an antigen defined by the monoclonal antibody KMO1 from tissue culture supernatant as a glycoprotein and from cancer cells as a glycolipid. The antigenic determinant was a carbohydrate. Antibody KMO1 inhibited the binding activity of 19-9 to CA19-9, but 19-9 antibody did not inhibited the binding activity of KMO1 to KMO1 antigen. The glycolipid antigen of KMO1 was a monosialoganglioside and was separated into 3 components on thin layer chromatography. The 19-9 antibody reacted with one of the components. These results suggest that the KMO1 antigen is similar to but not identical to CA19-9.