CD43 and CD49d from the B-Cell Chronic Lymphoproliferative Disorders Diagnostic Panel Are Useful to Detect Erythroid Dysplasia

BACKGROUND Despite bone marrow (BM) immunophenotyping by flow cytometry has progressively been recognized as an important tool for the diagnosis of myelodysplastic syndromes (MDS), the sparse knowledge about normal erythroid maturation and the lack of markers for erythroid characterization is a major shortcoming. METHODS Here, we analyzed the expression of CD43 and CD49d, two markers included in the diagnostic panel for B-cell chronic lymphoproliferative disorders (B-CLPD), in the CD34+ compartment of normal BM and along the normal and dysplastic erythroid maturation. For this, 13 normal BM aspirates and 18 BM aspirates from MDS patients were studied by flow cytometry. RESULTS Normal BM presented a higher expression of CD43 and CD49d among CD34+ erythroid precursors, compared to CD34+ cells committed to the remaining hematopoietic cell lineages. CD43 expression progressively decreased along the normal erythroid maturation, whereas CD49d levels increased from Stage I to Stage II, were maintained in Stages II and III, and then decreased until the last stage of maturation. In MDS, the expression of CD43 and CD49d followed a similar pattern, but with decreased expression levels for both markers, observed in all erythroid maturation stages (P < 0.05). CONCLUSIONS Our results point to the usefulness of CD43 and CD49d, two markers commonly present in B-CLPD diagnosis panels, in the identification of dysplastic phenotypic features in the erythroid lineage. This allows a feasible and inexpensive way to identify patients who would benefit from a more extensive study to evaluate the presence of MDS, during the processing of suspected B-CLPD samples. © 2019 International Clinical Cytometry Society.