Range Determination of Antigen Expression in Myeloid, Erythroid and Lymphoid Cell Lineages among Patients with Myelodysplastic Syndrome

Background: Myelodysplastic syndrome is a mixed clonal disorder of bone marrow progenitor cells. Understanding the pattern of the different lineage-specific, immature, and mature markers in myelodysplastic syndrome will help in setting-up the frame of reference to diagnose. Patients and Methods: We compared 60 bone marrow samples from 30 newly-diagnosed patients with myelodysplastic syndrome and 30 patients with idiopathic thrombocytopenic purpura as the control to perform a quantitative analysis of the antigen expression patterns in granulocytic, monocytic, erythroid and lymphoid lineages and myeloid precursors. Results: Quantitative analysis of CD markers, showed that the mean percentages of CD33, CD13, CD11b, HLA-DR, CD10 and CD34 positive granulocytes were 91%, 84.98%, 77.20%, 14.59%, 40.34% and 34.25%, respectively in myelodysplastic syndrome and 96.89%, 91.57%, 81.47%, 10.56%, 58.30% and 32.37%, respectively in idiopathic thrombocytopenic purpura. Flow cytometric analysis of erythroid lineage showed the mean percentage of CD71 in myelodysplastic syndrome and idiopathic thrombocytopenic purpura cases to be 64.54% and 83%, respectively. Investigation of antigen expression in the myeloid precursors of myelodysplastic syndrome patients showed the mean proportions of: 19.89%, 59.53%, 57.26%, 69.24%, 60.64% and 23.43% for CD117, CD34, HLA-DR, CD33, CD13 and CD11b, respectively. Also, idiopathic thrombocytopenic purpura cases showed the mean percentages of 11.73%, 45.67%, 58.90%, 74.28%, 70.16% and 15.66% for CD117, CD34, HLA-DR, CD33, CD13 and CD11b, respectively. Conclusion: There is no doubt that providing the reference values for an antigen expression pattern among myelodysplastic syndrome cases enhances the utility of flow cytometric analysis interpretation among these patients. Keywords: Myelodysplastic syndromes, flow cytometry, immunophenotyping, antigen expression.