title: CD79a is heterogeneously expressed in neoplastic and normal myeloid precursors and megakaryocytes in an antibody clone-dependent manner.
abstract: CD79a, a component of the B-cell antigen receptor complex, can also be expressed in certain non-B-cell malignancies. The reported frequency of CD79a expression in acute myeloid leukemias (AML) ranges from 0% to 90%. We evaluated 39 bone marrow biopsy specimens (29 AML and 10 normal cases) using 5 different commercially available anti-CD79a monoclonal antibody (MoAb) clones. Of 7 acute promyelocytic leukemia (APL) cases, 6 (86%) stained for CD79a with clones HM47/A9 (Novocastra, Newcastle Upon Tyne, England) and HM57 (DAKO, Carpinteria, CA) but were negative with clones 11E3 (Novocastra), and JCB117 (DAKO). Half of 6 acute megakaryoblastic leukemia (AMKL) cases and normal megakaryocytes in 14 (67%) of 21 cases were immunoreactive using clone 11D10 (Novocastra). Approximately one third of non-APL/non-AMKL AML and myeloid precursors in normal marrow specimens stained with clones HM57 and 11D10. This heterogeneity of CD79a expression in AML, megakaryocytes, and myeloid precursors is MoAb clone-dependent, likely owing to different epitope detection, and may be of diagnostic usefulness.
authors.affiliation: Department of Pathology and Laboratory Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
authors.forename: Parul
authors.initials: P
authors.lastname: Bhargava
authors.forename: Bhaskar V S
authors.initials: BV
authors.lastname: Kallakury
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Ross
authors.forename: Norio
authors.initials: N
authors.lastname: Azumi
authors.forename: Adam
authors.initials: A
authors.lastname: Bagg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000276:immunology; D001854:Bone Marrow Cells / Q000737:chemistry*; D051925:CD79 Antigens / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism*; D008297:Male; D008533:Megakaryocytes / Q000737:chemistry*; D008875:Middle Aged
chemical_list: D000911:Antibodies, Monoclonal; D051925:CD79 Antigens; C497881:CD79A protein, human