title: Generation of bispecific monoclonal antibodies for two phase radioimmunotherapy.
abstract: A two phase radioimmunotherapy based on bispecific MAbs in which one arm recognises a tumour antigen and the other a radiolabelled chelate, may prove more effective in the treatment of carcinomas than currently available immunotherapies. To establish this system we first showed that penetration into human carcinoma xenografts as well as long term retention of intact MAb outside the carcinoma cells can be obtained. Epitope saturation was not obtained however, despite the large MAb doses injected i.v. for 10 days. We then generated hybridomas producing high avidity anti-metal chelate MAbs (anti-DTPA-Y). These hybridomas were fused with hybridomas producing MAbs against CEA or GIT-mucin, and stable bispecific MAb producing quadromas were obtained. For the anti-GIT-mucin x anti-chelate MAb a purification procedure based on double anti-idiotype affinity chromatography was shown to result in greater than 95% pure bispecific immunoreactive MAb. Comparative in vivo stability studies profiled DTPA-Y as the chelate of choice for in vivo application.
authors.affiliation: Research Laboratories of Behringwerke AG, Marburg/Lahn, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Bosslet
authors.forename: A
authors.initials: A
authors.lastname: Steinstraesser
authors.forename: P
authors.initials: P
authors.lastname: Hermentin
authors.forename: L
authors.initials: L
authors.lastname: Kuhlmann
authors.forename: A
authors.initials: A
authors.lastname: Bruynck
authors.forename: M
authors.initials: M
authors.lastname: Magerstaedt
authors.forename: G
authors.initials: G
authors.lastname: Seemann
authors.forename: A
authors.initials: A
authors.lastname: Schwarz
authors.forename: H H
authors.initials: HH
authors.lastname: Sedlacek
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D003110:Colonic Neoplasms / Q000378:metabolism / Q000532:radiotherapy*; D006801:Humans; D007275:Injections, Intravenous; D051379:Mice; D008819:Mice, Nude; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000532:radiotherapy*; D004369:Pentetic Acid / Q000378:metabolism / Q000627:therapeutic use*; D014407:Tumor Cells, Cultured; D015021:Yttrium Radioisotopes / Q000378:metabolism / Q000627:therapeutic use*
chemical_list: D000911:Antibodies, Monoclonal; D015021:Yttrium Radioisotopes; D004369:Pentetic Acid