干扰素α对慢性髓系白血病来源的树突状细胞表达Fas／FasL的影响

本研究探讨干扰素α对慢性髓系白血病（CML）来源的树突状细胞（DC）表达Fas／FasL的影响。在CML—DCs的培养液中除加入SCF，GM—CSF，TNF—α及IL-4外，还加入IFN—α。培养10-14天，除了鉴定细胞免疫表型和Ph^1染色体比例外，还应用流式细胞仪检测细胞表达Fas／FasL比例，用PI染色分析细胞凋亡，ELISA法检测上清液sFas含量。结果表明：加入IFN-α后，CML—DC共刺激分子的表达显著改善，Ph^1（＋）细胞比例随IFN—α浓度增加而减低；培养细胞Fas的表达上调，sFas含量却下降，FasL表达阴性，细胞凋亡比例增加。结论：IFN—α在改善CML-DC表型同时，可通过Fas途径促进Ph^1（＋）细胞凋亡，使Ph^1（-）细胞数量相对增加。

Influence of Interferon a on Expression of Fas and Fas Ligand in Dendritic Cells from Patients with Chronic Myeloid Leukemia

The study was aimed to investigate the influence of interferon alpha (IFN-alpha) on the expressions of Fas and Fas ligand (FasL) in dendritic cells (DCs) from patients with chronic myeloid leukemia (CML). In addition to adding stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor alpha (TNF-alpha) and interleukin 4 (IL-4), the IFN-alpha was added to the serum-free medium for DCs. After culturing for 10 - 14 days, cell phenotype and percentage of Ph(1) chromosome were detected by different methods. The expression of Fas or FasL on CML-DCs and cell cycle of DCs labeled with propidium iodine (PI) were measured by flow cytometry. The concentration of sFas in supernatants was analyzed by enzyme-linked immunosorbent assay (ELISA). The results indicated that the expression of co-stimulatory molecules were improved significantly while the percentages of Ph(1) positive cells decreased. The level of Fas on cells was up-regulated and the concentration of sFas decreased. However, the expression of FasL was negative. The ratio of apoptosis rose gradually while the concentration of IFN-alpha increased. It is concluded that IFN-alpha can accelerate the apoptosis of Ph(1) positive cells through Fas/FasL pathway, so the number of Ph(1) negative cells increases relatively.