Immunophenotypic changes of monocytes in myelodysplastic syndrome and clinical significance

BACKGROUND: Myelodysplastic syndrome (MDS) is a type of heterogeneous myeloid clonal disorder usually diagnosed based on a combination of multiple laboratory examinations, including analysis of peripheral blood cells, bone marrow cell morphology and cytogenetics. However, there is a certain difficulty in cases with no distinct changes in hematology and marrow cell morphology. METHODS: We adopt flow cytometry to quantitatively analyze the immunophenotypic changes of marrow monocytes according to the surface antigens and their combinations at different differentiation stages, so as to study the changes of monocytes during differentiation in patients with bone marrow failure. In the meantime, the relationship between the immunophenotypic changes of marrow monocytes and IPSS-R score and prognosis of MDS patients was analyzed. RESULTS: Our results demonstrated disorders of maturation and differentiation of monocytes in patients with MDS and clonal cytopenias of undetermined significance as compared to those with aplastic anemia and healthy individuals. In addition, the differentiation abnormality gradually increased with the disease progression. Furthermore, CD300e expression was found to show significant associations with the clinical stage and disease progression of MDS, and the progression-free survival and AML-free survival were much longer in MDS patients highly expressing CD300e on monocytes. CONCLUSIONS: CCUS and MDS patients have disorders of differentiation and maturation of monocytes, which tends to be more critical with MDS progression or transforms to AML. Moreover, high CD300e expression has the potential to be a favorable prognostic marker for MDS. This study provides important insights to the role of monocyte immunotyping in the diagnosis, differentiation and prognosis of MDS. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10238-022-00856-7.