VALUABLE AND COST EFFECTIVE COMBINATION OF CD123 AND CD22 FOR BASOPHIL DISCRIMINATION
ABSTRACT: Although the phenotypic features of basophils have been highlighted in literatures, yet some labs generate confusion while discriminating blasts from basophil gate in flow cytometry analysis. This is sometimes due to the overlap of different population on CD45 side scatter plot, and in other situations due to lack of markers which highlight basophils due to financial jeopardy. Aim of the study: Selection of a proper combination of markers with unique expression on basophils to clearly highlight basophils especially in under-resourced labs with limited budget. Methods: Comprehensive basophil phenotyping applied on 40newly diagnosed cases of CML and 20 cases of regenerating marrow post chemotherapy for Precursor B lymphoblastic leukemia with no evidence of abnormal cellsas control. Flow cytometry markers used were CD45, CD38, CD71, CD33, CD22, CD123, HLA-DR, CD34, CD117, CD3, CD4, CD8, CD56, CD11b, HLA-DR and CD15. Results: Basophils from patients and control samples were clearly discriminated from blasts and lymphocytes by using CD123 and CD22, a unique pattern of expression with perfect back-gating on CD45 side scatter plot which proved the discrimination. Conclusion: CD123 and CD22 will clearly discriminate basophils from different types of population which may occupy the window area as myeloblast, precursor B cells (hematogones), abnormal B cells (lymphoblasts) and mature B cells. This combination should therefore be part of the screening panel used as first line along with CD45in labs with limited budget.
Ok