Study on the ratio of CD34 positive cells and granulocyte colony stimulating factor receptor on CD34 positive cells in bone marrow of the patients with aplastic anemia and myelodysplastic syndrome

Objective:To detect the ratio of CD34 positive cells in bone marrow mononuclear cells and the expressive rate of granulocyte colony-stimulating factor receptor(G-CSFR) on CD34 positive cells in bone marrow of the patients with aplastic anemia (AA) and myelodysplastic syndrome(MDS). Method:The ratio of CD34 positive cells in bone marrow mononuclear cells and the expressive rate of G-CSFR on cells of 13 AA patients, 22 MDS patients and 12 normal subjects were detected by flow cytometry(FCM). Result:There was significant difference according to the ratio of CD34 positive cells in mononuclear cells of bone marrow between AA group and control group, AA group and MDS group, MDS-RA group and MDS-RAEB group (P0.05) but there was no significant difference according to the expressive rate of G-CSFR on CD34 positive cells. The ratio of CD34 positive cells in mononuclear cells of bone marrow was less than 0.1% in the majority of SAA patients(3/4) while it was seldom less than 0.1% in CAA patients. Most MDS patients(7/9) with low G-CSFR expression had neutropenia of the peripheral blood. Neutropenia was less common in the normal expression group(1/6), but also occurred in the high expression group(3/7).Conclusion:The reduction of hematopoietic stem cells is one of the principal pathogenesis of AA , but the expressive rate of G-CSFR on CD34 positive cells in bone marrow isn't a main factor. The increased ratio of CD34 positive cells in bone marrow of MDS patients may be a poor prognostic indicator. The determination of G-CSFR on CD34 positive cells in bone marrow can partly explain why MDS patients have neutropenia of the peripheral blood.