title: CD79a: a novel marker for B-cell neoplasms in routinely processed tissue samples.
abstract: The CD79 molecule, comprising two polypeptide chains, mb-1 (CD79a) and B29 (CD79b), is physically associated in the B-cell membrane with immunoglobulin. It transmits a signal after antigen binding and may, therefore, be considered the B cell equivalent of CD3. It appears before the pre-B-cell stage, and the mb-1 (CD79a) chain can still be present at the plasma cell stage. In this report, we describe a new anti-CD79a monoclonal antibody, JCB117, which reacts with human B cells in paraffin embedded tissue sections, including decalcified bone marrow trephines. When tested on a total of 454 paraffin embedded tissue biopsies, gathered from a number of different institutions, it reacted with the great majority (97%) of B-cell neoplasms, covering the full range of B-cell maturation, including 10 of 20 cases of myeloma/plasmacytoma. It is of interest that the antibody labels precursor B-cell acute lymphoblastic leukemia samples, making it the most reliable B-cell marker detectable in paraffin-embedded specimens in this disorder. All neoplasms of T cell or nonlymphoid origin were negative, indicating that antibody JCB117 may be of value to diagnostic histopathologists for the identification of B-cell neoplasms of all maturation stages.
authors.affiliation: University Department of Cellular Science, John Radcliffe Hospital, Oxford, UK.
authors.forename: D Y
authors.initials: DY
authors.lastname: Mason
authors.forename: J L
authors.initials: JL
authors.lastname: Cordell
authors.forename: M H
authors.initials: MH
authors.lastname: Brown
authors.forename: J
authors.initials: J
authors.lastname: Borst
authors.forename: M
authors.initials: M
authors.lastname: Jones
authors.forename: K
authors.initials: K
authors.lastname: Pulford
authors.forename: E
authors.initials: E
authors.lastname: Jaffe
authors.forename: E
authors.initials: E
authors.lastname: Ralfkiaer
authors.forename: F
authors.initials: F
authors.lastname: Dallenbach
authors.forename: H
authors.initials: H
authors.lastname: Stein
mesh_terms: D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm / Q000276:immunology; D000918:Antibody Specificity; D015703:Antigens, CD / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D014408:Biomarkers, Tumor / Q000276:immunology*; D051925:CD79 Antigens; D006801:Humans; D007150:Immunohistochemistry; D015448:Leukemia, B-Cell / Q000175:diagnosis*; D010232:Paraffin; D011947:Receptors, Antigen, B-Cell / Q000032:analysis*
chemical_list: D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D051925:CD79 Antigens; C497881:CD79A protein, human; D011947:Receptors, Antigen, B-Cell; D010232:Paraffin