Characterization of the carcinoembryonic antigen activity associated with cyst fluids of mucinous ovarian cystadenocarcinoma.

Cyst fluids from mucinous cystadenocarcinoma of the ovary show significant concentrations of carcinoembryonic antigen (CEA) activity. This CEA activity was compared to several colon CEA standards with respect to size, concanavalin A binding, and immunological activity. CEA activity in unfractionated ovarian cyst fluid was indistinguishable from CEA standards by gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The cyst fluid CEA activity showed identity with various CEA standards by double immunodiffusion in agar gels and by radioimmune competition assay. Attempts to purify the cyst fluid CEA by perchloric acid extraction prior to gel filtration chromatography were unsuccessful. The yield of soluble CEA activity following perchloric acid extraction averaged 10%, and in one cyst fluid, qualitative changes were noted in the soluble antigenic activity. Ovarian cyst fluid CEA activity was bound by concanavalin A-Sepharose 4B and specifically eluted with competing monosaccharide. Lectin affinity chromatography and gel filtration chromatography over Sepharose 4B and Sephadex G-200 can be used to purify cyst fluid CEA from whole fluid or lyophilized and reconstituted samples.