Effect of IL-15 on the proliferation of CD34~+ cells in patients with MDS

Objecttve:To explore the effect of IL-15 on CD34 + cells in patients with MDS. Method:The CD34 + cells were separated by magnetic bead-activated cell sorter (MACS) system. The IL-15 group and the control group were cultured in fluid and methylcellulose semisolid medium, respectively. MTT colorimetry was used to examine the inhibitory effect of IL-15 on the proliferation of MDS CD34 + cells.The numbers of CD34 + cells and colony formation of CFU-E, BFU-E, CFU-G, CFU-GEMM were counted after culture. The change of cell-cycle were analysised by FCM.Result:The ratio of CD34 + cell , the rate of recovery,the purity of CD34 + cells in positive fraction and the enrich rate were all reach requirment. MTT colorimetry detection that IL-15 could inhibit the proliferation of MDS CD34 + cells.The optimum time of inhibiting CD34 + cell proliferation by IL-15 was 8 days and optimal dosage of IL-15 was 20 μg /L.The MDS CD34 + cells were cultured 8 days using the concentration of 0 μg/l (controlled group) and 20 μg/l (treated group) IL-15. The cell counting and the rates of colony formation of control group were significantly different with IL-15 groups. The ratio of G 1, S and G 2 in cell-cycle of CD34 + cell were pronouncedly difference as compared with test group.Conclusion:It is suggested that IL-15 could stimulates the proliferation of MDS CD34 + cells. IL-15 may obviously have synergy effect with other cytokines. IL-15 may play a role in therapying patients with MDS.