Purification and Characterization of Carcinoembryonic Antigen from GW-39, a Xenografted Human Colonic Tumor System

Abstract

Carcinoembryonic antigen (CEA) was purified from GW-39 human tumor xenografts in hamsters by immunoaffinity chromatography. Binding of the antigen to immobilized monoclonal antibody provided a high degree of purification of CEA in a single step. A recovery of 79% and a 750-fold purification were obtained. The purified CEA has a molecular size of 180 kilodaltons, an isoelectric point of 4.4, and a specific activity of 0.94. About 73% of the radiolabeled GW-39 CEA reacted with goat anti-CEA serum. The amino acid and carbohydrate compositions of the GW-39 CEA were comparable to those of CEA preparations from other sources.

Selective binding of carcinoembryonic antigen using imprinted polymeric hydrogels

“…Carcinoembryonic antigen (CEA) is a 180 kDa glycosylated surface protein overexpressed on most human adenocarcinomas including colon, rectum, pancreas, and breast 1. CEA is a globular protein, soluble in water, with an isoelectric point of ∼4.7 2. The low isoelectric point of CEA suggests that the protein has an overall negative charge in its native environment within the body.…”

Technetium-labeling of monoclonal antibodies with functionalized BATOs: 2. TcCl(DMG)3CPITC (CPITC=carboxyphenylisothiocyanate) labeling of B72.3 and NP-4 whole antibodies and NP-4 F(ab')2

“…A TAG-72-Reacti-Gel affinity column in a RAININ Leur-lock column, with a 2.5-mL bed volume, was prepared in-house (1). A CE A-Affi-Gel-10 affinity column was prepared using CEA extracted from GW-39 human colonic tumor xenograft (13).…”

“…A Phast SDS-PAGE electrophoresis system (Pharmacia) was used for the characterization of 99mTc-labeled antibodies and antibody fragments using [10][11][12][13][14][15] % gradient gels and the reagents, buffers, separation protocols, and development methods recommended by the manufacturer.…”

Highly Effective Extraction of Carcinoembryonic Antigen with Phosphatidylinositol-Specific Phospholipase C

“…In accordance with the widespread use of clinical CEA assays such as radioimmunoas say (RIA) or enzyme immunoassay, the de mand for purified CEA preparations as cali bration standards or reference antigens is now rapidly increasing. Purification of CEA using perchloric acid (PCA) extraction and gel filtration as reported by Krupey et al [3] has been the most popular method, although several improved procedures have also been reported [4][5][6].…”