EB病毒对脐带血单核细胞来源树突状细胞凋亡的影响

目的观察EB病毒（EBV）感染对新生儿脐带血单核细胞来源的树突状细胞（DC）凋亡的影响。方法用重组人粒细胞-巨噬细胞集落刺激因子（rhGM—CSF）（50 ng／mL）和重组人白细胞介素-4（rhIL-4）（10ng／mL）诱导脐带血单核细胞向DC分化，将DC分为3组：①4G组：细胞分离当天单独加入rhGM—CSF和rhIL-4；②4G＋0dEBV组：细胞分离当天同时加入rhGM—CSF、rhIL-4和B95．8细胞上清；③4G＋5dEBV组：细胞分离当天加入rhGM—CSF和rhIL-4，培养至第5天后加入B95．8细胞上清。Annexin V—FITC和PI染色流式细胞术检测DC的凋亡百分比；Western Blot检测X-连锁凋亡抑制蛋白（XIAP）的表达。结果培养至第6～14天，4G＋0d EBV组DC凋亡百分比明显高于4G组（P〈0．05）；第7～14天，4G＋5d EBV组DC凋亡百分比明显高于4G组（P〈0．05）。EBV在不同感染时间点感染DC，对DC凋亡百分比的影响不同。经EBV感染的DC，XIAP的表达明显降低。结论EBV感染促进了脐带血单核细胞来源DC的凋亡，这种促进作用与DC的分化成熟状态有关。

Effects of Epstein-Barr virus on apoptosis of cord blood monocytes-derived dendritic cells

Objective To investigate the effects of Epstein-Barr virus (EBV) infection on apoptosis of cord blood monocytes-derived dendritic cells (DC) in neonates. Methods Cord blood monocytes were induced into DC by 50 ng/mL recombinant human granulocyte macrophage colony-stimulating factor(rhGM-CSF)and 10 ng/mL recombinant human interleukin-4 (rhIL-4),and DC were divided into three groups:①4G group:rhGM-CSF and rhIL-4 were added separately on the day of cell separation;②4G+0d EBV group:rhGM-CSF,rhIL-4 and B95.8 cell supernatants were added simultaneously on the day of cell separation;③4G+5d EBV group:hGM-CSF and rhIL-4 were added on the day of cell separation,and B95.8 cell supernatants were added on the 5th day.Percents of DC apoptosis were measured using Annexin V-FITC and PI staining by flow cytometry.The expression of X-linked inhibitor of apoptosis protein (XIAP) was detected by Western Blot.Results Percent of DC apoptosis in 4G+0d EBV group was significantly higher than that in 4G group on the 6th to 14th day(P<0.05),and percent of DC apoptosis in 4G+5d EBV group was significantly higher than that in 4G group on the 7th to 14th day(P<0.05).The effects of EBV infection on percent of DC apoptosis had relations with infection time points.The expression of XIAP in DC decreased significantly after EBV infection. Conclusion EBV promotes apoptosis of cord blood monocytes-derived DC,which is associated with the differentiation and maturation status of DC.