CD79a surface staining: a useful marker of mature B cells

Cytoplasmatic expression of CD79a is one of determining criteria for flow cytometry diagnosis of B cell precursor acute lymphoblastic leukemia (BCP ALL). On the contrary to mature B cells (including mature B cell lymphoproliferation), BCP ALL blasts typically do not express surface CD79a. Therefore, surface CD79a expression can be helpful in discriminating BCP ALL from mature B cell lymphoproliferations such as Burkitt lymphoma (BL). Both BL and majority of BCP ALL cases are CD19 and CD10 positive. Helpful markers for discriminating these two categories are CD34, TdT (both negative in BL) and immunoglobulin light chains kappa (IgK) or lambda (IgL) (single positive in BL). Nevertheless, CD34 is negative in significant number of BCP ALL cases and TdT staining requires longer protocol with fixation and permeabilization. IgK and IgL staining requires cautious washing of sample to reduce serum immunoglobulines, which prolongs the time-to-analysis. Therefore, CD79a surface staining can be of additional value to above mentioned markers. Moreover, in rare cases of CD19 deficiency or its downregulation after targeted treatment in mature B cell proliferations, it might become a new promising marker for detecting mature B cells.

Michaela Novakova, M.D., Ph.D.
LinkedIn / OrcidID
CLIP-cytometry
Department of Paediatric Haematology and Oncology
Charles University and University Hospital Motol

EXBIO PRODUCTS RELATED TO THIS BLOG:

Anti-Hu CD79a antibodies:

Clone	Specificity
ZL7.4	The mouse monoclonal antibody ZL7.4 interacts with extracellular domain of CD79a (Ig alpha), a 40-45 kDa subunit of B cell antigen-specific receptor (BCR) and its early developmental forms.
HM47	The mouse monoclonal antibody HM47 reacts with intracellular domain of CD79a (Ig alpha), a 40-45 kDa subunit of B cell antigen-specific receptor (BCR) and its early developmental forms.
HM57	The mouse monoclonal antibody HM57 reacts with intracellular domain of CD79a (Ig alpha), a 40-45 kDa subunit of B cell antigen-specific receptor (BCR) and its early developmental forms.

Anti-Hu CD19 antibodies:

Clone	Specificity
LT19	The antibody LT19 reacts with an extracellular epitope of CD19 (B4), a 95 kDa type I transmembrane glycoprotein (immunoglobulin superfamily) expressed on B lymphocytes and follicular dendritic cells; it is lost on plasma cells.
4G7	The mouse monoclonal antibody 4G7 recognizes an extracellular epitope of human CD19.

 

Anti-Hu CD10 antibodies:

Clone	Specificity
MEM-78	The antibody MEM-78 reacts with an extracellular epitope CD10 antigen (CALLA - Common acute lymphatic leukemia antigen), a 100 kDa type II integral membrane protein.
LT10	The antibody LT10 reacts with an extracellular epitope of CD10 (CALLA - Common acute lymphatic leukemia antigen), a 100 kDa type II integral membrane protein.

 

Anti-Hu CD20 antibodies:

Clone	Specificity:
2H7	The mouse monoclonal antibody 2H7 recognizes an extracellular epitope on CD20 (B1, Bp35), a 33-37 kDa non-glycosylated membrane receptor with four transmembrane domains, expressed on pre-B lymphocytes, resting and activated B cells (not plasma cells), follicular dendritic cells, and at low levels on peripheral blood T lymphocytes.
LT20	The antibody LT20 reacts with an extracellular epitope of CD20 (Bp35), a 33-37 kDa non-glycosylated membrane receptor with four transmembrane domains, expressed on B lymphocytes (it is lost on plasma cells), follicular dendritic cells, and at low levels on peripheral blood T lymphocytes.