title: Characterization and applications of a newly developed rabbit monoclonal antibody to cytokeratin 7 (CK7) for immunohistochemistry.
abstract: In this paper, we describe the development of a novel rabbit monoclonal cytokeratin 7 (CK7) antibody. CK7 is widely used in immunohistochemical tests that are commonly performed in histopathology laboratories. Rabbits were immunized with a peptide corresponding to C-terminus of CK7. Recombinant monoclonal antibodies were developed using proprietary technology. Antibodies were screened by enzyme-linked immunosorbent assay against CK7 peptide, and the specificity of the antibody was verified by Western blotting on Hela cell lysates and by immunohistochemical staining on formalin-fixed paraffin-embedded tissue sections. One clone, designated as BC1 was selected and tested on a variety of human tissues. Its reactivity was tested and compared with a well-characterized mouse monoclonal CK7 antibody OV-TL 12/30 on lung, breast, ovarian, and colon cancers, and on a variety of normal tissues. The staining patterns and specificity were concordant with mouse monoclonal OV-TL 12/30. The BC1 clone, however, showed superior staining to OV-TL 12/30 in terms of intensity and staining of debris. CK7 combined with CK20 or CDX2 and TTF1 is a common panel used in histopathology laboratories in discrimination between primary adenocarcinomas and metastatic lung adenocarcinomas from colonic origin. We then developed a 4-step double stain (multiplex) assay by combining CDX-2 with CK7 in an antibody cocktail and tested the efficacy on lung, breast, and colon cancers. Results showed that this novel antibody can be used as a single component and/or in combination with CDX2 and TTF1 in applications for diagnostic pathology.
authors.affiliation: Biocare Medical, LLC, Concord, CA 94520, USA. wqi@biocare.net
authors.forename: Weimin
authors.initials: W
authors.lastname: Qi
authors.forename: Joseph
authors.initials: J
authors.lastname: Chu
authors.forename: Ding
authors.initials: D
authors.lastname: Zhou
authors.forename: David
authors.initials: D
authors.lastname: Tacha
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000473:pathology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology; D000071616:CDX2 Transcription Factor; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7 / Q000032:analysis*; D008175:Lung Neoplasms / Q000175:diagnosis / Q000473:pathology; D051379:Mice; D009369:Neoplasms / Q000175:diagnosis* / Q000473:pathology; D010051:Ovarian Neoplasms / Q000175:diagnosis / Q000473:pathology; D011817:Rabbits; D046888:Tissue Array Analysis
chemical_list: D000911:Antibodies, Monoclonal; D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; D053552:Keratin-7