title: Improved radioimmunolocalization of carcinomas using Fab fragments with anti-CEA specificity.
abstract: A model system with human colonic grafts containing carcinoembryonic antigen (CEA) in nude mice was used to improve specificity and sensitivity of the radioimmunolocalization method. Monoclonal antibody MAb I-38S1 and monkey anti-CEA appeared to have high in vitro and in vivo specificity. Fab fragments of MAb I-38S1 improved localization ratios. A reduced time for optimal immunolocalization was obtained with Fab compared with MAb of the same specificity. Combinations of Fab:s, vasoactive compounds or anti-IgG treatment to reduce background levels did not further improve speed of localization or sensitivity.
mesh_terms: D000469:Alkaline Phosphatase; D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000276:immunology; D002277:Carcinoma / Q000175:diagnosis* / Q000276:immunology; D058851:GPI-Linked Proteins; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000276:immunology*; D007457:Iodine Radioisotopes; D007527:Isoenzymes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D000911:Antibodies, Monoclonal; D002272:Carcinoembryonic Antigen; D058851:GPI-Linked Proteins; D007140:Immunoglobulin Fab Fragments; D007457:Iodine Radioisotopes; D007527:Isoenzymes; D000469:Alkaline Phosphatase; C019839:alkaline phosphatase, placental