Modified cytokeratins expressed on the surface of carcinoma cells undergo endocytosis upon binding of human monoclonal antibody and its recombinant Fab fragment.

ABSTRACT: Previously, we have reported on successful imaging of colon, rectal, and pancreatic carcinomas in patients by using a radiolabeled all-human monoclonal antibody, COU-1, directed against modified cytokeratin. To further develop this antibody for use as an immunoconjugate, COU-1 was cloned by phage display selection and the human Fab fragment was expressed in bacteria. Analysis by confocal laser scanning microscopy demonstrated that COU-1 bound in a uniform punctate pattern to the surface of viable carcinoma cells stained at 4 degrees C, and binding increased significantly when cells were cultured on fibronectin, laminin, or collagen IV. In the case of fibronectin, COU-1 staining was particularly enhanced at intercellular junctions. When carcinoma cells were cultured with COU-1 at 37 degrees

SUBMITTER: Ditzel HJ 

PROVIDER: S-EPMC21565 | biostudies-literature | 1997 Jul

REPOSITORIES: biostudies-literature