Background: The diagnosis of B-cell acute lymphoblastic leukemia (B-ALL) on the basis of the World Health Organization (WHO) recommendations in 2016 requires the expression of CD19 with CD79a (CD79a), cCD22 and CD10. CD79a is an integral B cell antigen expressed at all stages. Its absence in B-ALL has only been rarely reported. In this study, we described three cases of B-ALL showing complete l...

The role of myeloid derived suppressor cells (MDSCs) in promoting tumorigenesis is well-established, and significant effort is being made to further characterize surface markers on MDSCs both for better diagnosis and as potential targets for therapy. Here we show that the B cell receptor adaptor molecule CD79a is unexpectedly expressed on immature bone marrow myeloid cells, and is upregulated o...

CD79a and CD79b function as transducers of B cell antigen receptor signals via a cytoplasmic sequence, termed the immunoreceptor tyrosine-based activation motif (ITAM). ITAMs contain two conserved tyrosines that may become phosphorylated upon receptor aggregation and bind distinct effectors by virtue of the distinct preference of phosphotyrosyl-containing sequences for SH2 domains. To explore t...

Aberrant expression of CD79a has been reported in neoplastic cells in peripheral T cell lymphoma, T-cell acute lymphoblastic leukemia and acute myeloid leukemia (especially those with t(8;21)). In this report, we document the first report of CD79a positivity in erythroid precursor cells in bone marrow. In all, we document this finding in five of 18 re-staging bone marrow trephine samples in pat...

Background: The diagnosis of B-cell acute lymphoblastic leukemia (B-ALL) on the basis World Health Organization (WHO) recommendations in 2016 requires expression CD19 with CD79a (CD79a), cCD22 and CD10. is an integral B cell antigen expressed at all stages. Its absence B-ALL has only been rarely reported. In this study, we described three cases showing complete loss or extremely weak CD79a. Met...

Terminal deoxynucleotidyl transferase (TdT)-positive cells in human bone marrow (BM) are a phenotypically inhomogeneous population of precursor cells. In their majority, these TdT+ cells are unambiguously committed to the B lineage, as evidenced by CD19 expression. However, TdT+ precursors that lack CD19 also exist and these may encompass a differentiation potential for the B as well as for oth...

Follicular lymphoma is characterised by the t(14;18)(q32;q21) chromosomal translocation causing BCL2 protein overexpression. A proportion of follicular lymphomas do not carry the t(14;18) translocation and lacked BCL2 protein expression. We describe a case of a BCL2 protein- and t(14;18)-negative follicular lymphoma that caused diagnostic difficulty. The usefulness of several immunomarkers incl...

MILNER, R.J., PEARSON, J., NESBIT, J W. & CLOSE, P. 1996. 1mmunophenotypic classification of canine malignant lymphoma on formalin-fixed paraffin wax-embedded tissue by means of CD3 and CD79a cell markers. OnderStepoort Journal of Veterinary Research, 63:309313 Canine malignant lymphoma (CML) is a common lymphoid tumour. Identification of the immunophenotype is of prognostic importance;T-cellly...

The transcription factor PAX5 plays a key role in the commitment of hematopoietic precursors to the B-cell lineage, but its expression in acute leukemias has not been thoroughly investigated. Hereby, we analyzed routine biopsies from 360 acute leukemias of lymphoid (ALLs) and myeloid (AMLs) origin with a specific anti-PAX5 monoclonal antibody. Blasts from 150 B-cell ALLs showed strong PAX5 nucl...

Background: Flow cytometric analysis of leukemias improves accuracy for distinguishing acute leukemias of myeloid and lymphoid origin. In rare cases, both myeloid and lymphoid antigens are expressed, creating ambiguity for lineage assignment and difficulties in diagnosis of leukemia. Aberrant antigen expression in acute myeloid leukemia (AML) is recognized to be a poor prognostic indicator. CD7...