CD Markers
CD79a
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: CD79a[title]
See Also: CD79b
CD79a
Author: Nat Pernick, M.D.
Last author update: 1 February 2002
Last staff update: 14 May 2021
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: CD79a[title]
See Also: CD79b
Table of Contents
Definition / general | Uses by pathologists | Microscopic (histologic) images | Positive staining - normal | Positive staining - disease | Negative stainingCite this page: Pernick N. CD79a. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cdmarkerscd79a.html. Accessed June 4th, 2023.
Definition / general
- Also called MB-1, B cell antigen receptor complex associated protein alpha-chain
- Encodes Ig-alpha protein of the B cell antigen receptor; the receptor also includes Ig-beta protein (CD79b) and surface immunoglobulin
- Expressed early in B cell differentiation (often positive when mature B cell markers are negative); also expressed in plasma cells
- In AML, presence usually represents aberrant B cell antigen in leukemias of distinct myeloid linage, not biphenotypic differentiation (Cancer Genet Cytogenet 2005;163:62)
- CLL patients have low B cell-IgM surface expression due to defects in glycosylation and folding in µ and CD79a chains (Blood 2005;105:2933)
- Less specific than PAX5 for acute leukemia (Cancer Res 2004;64:7399)
- OMIM #112205, Blood 1995;86:1453 (early study)
Uses by pathologists
- General detection of B cells / B cell origin (with CD20); also:
- In ALL or small B cell lymphoproliferative disorders when CD20 may be negative (Am J Clin Pathol 2006;126:534) or after rituximab (anti CD-20) therapy (Am J Surg Pathol 2005;29:1399)
- In infarcted lymphomas (Arch Pathol Lab Med 2003;127:60)
- To differentiate preB lymphoblastic lymphoma from Ewing’s sarcoma (Mod Pathol 2001;14:1175)
Microscopic (histologic) images
Images hosted on other servers:
Follicular dendritic cell tumor (fig 14)
Lymphoplasmacyte rich meningioma
Leukemia / lymphoma:
Pro B acute lymphoid leukemia (Figure 1, bottom left)
Primary mediastinal B cell lymphoma (Figure 4)
T cell lymphoblastic leukemia (Figure 2, middle right)
t(8;21) myeloid leukemia (Figure 3, bottom right)
Positive staining - normal
- B cells, plasma cells
Positive staining - disease
- B cell leukemia / lymphoma (but variable staining in plasmablastic lymphoma and primary effusion lymphoma); nodular lymphocyte predominant Hodgkin’s lymphoma (faint, Am J Clin Pathol 2003;119:192), classic Hodgkin’s lymphoma (18%, Mod Pathol 2004;17:1531), t(8,21) myeloid leukemias, T cell leukemias / lymphomas (some, Am J Clin Pathol 2000;113:823) and primary plasmacytoma of lymph node (Hum Pathol 1997;28:1083)
Negative staining
- Anaplastic large cell lymphoma (Hum Pathol 2004;35:455), granulocytic sarcoma
