Myeloidderived peripheral blood suppressor cells at haematopoietic stem cell mobilisation in multiple myeloma patients

Introduction . Multiple myeloma (MM) is a B-cell malignancy with clonal expansion of plasma cells in bone marrow. Highdose chemotherapy autologous haematopoietic stem cell transplantation among main consolidation therapies MM. Myeloid-derived suppressor (MDSCs) are immature myeloid-accompanying able to suppress the immune response. The administration granulocyte colony stimulating factor (G-CSF) mobilise (HSCs) increases MDSC count peripheral blood (PB). Aim — study subsets PB remission MM patients and their incidence dynamics at HSC mobilisation. Methods surveyed 35 prior after counts granulocytic (G-MDSCs; Lin–HLA-DR–CD33+ CD66b+), monocytic (М-MDSCs; CD14+ HLA-DRlow/–) early MDSCs (E-MDSCs; Lin–HLA-DR– CD33+ CD66b–) were estimated flow cytometry. Results Remission differed from healthy donors higher relative G-MDSCs (Lin–HLA-DR– CD66b+) increased absolute М-MDSCs (CD14+ HLA-DRlow/–). significantly outnumbered G-MDSCs. subset elevated complete response (CR) very good partial (VGPR), as well (PR). Higher associated greater pretreatment (2–3 lines chemotherapy). After mobilisation cyclophosphamide 2–4 g/m2 + G-CSF (filgrastim 5 μg/kg/day), median E-MDSC M-MDSC by 2.3 2.0 times, respectively, while G-MDSC raised 46-fold perturbing balance. Conclusion had both compared donors. A patient was counts. Treatment (CR/VGPR vs. PR) not coupled variation. G-CSF-induced entailed significant all three PB.