草分支杆菌对人脐血树突状细胞体外扩增的影响

背景：树突状细胞因其强大的抗原提呈能力而在机体抗肿瘤作用的中心地位逐渐受到重视,但如何能有效获得足够数量有功能的树突状细胞成为目前研究的重点,尤其是有关低毒免疫调节剂的报道较少。目的：观察草分支杆菌F.U.36（乌体林斯,Utilins）对人脐血来源树突状细胞体外扩增的影响。方法：应用Ficoll-Hypaque法分离人脐血单个核细胞,分别用乌体林斯,细胞因子（重组人粒细胞-巨噬细胞集落刺激因子＋重组人肿瘤坏死因子α＋重组人白细胞介素4）,细胞因子联合乌体林斯进行干预,并以RPMI-1640培养液诱导培养人脐血单个核细胞作为对照组,诱导培养树突状细胞,并于倒置显微镜下观察其生长情况及形态。培养第9天,采用流式细胞仪检测各组人树突状细胞特异性表型CD1a及MHC-Ⅱ分子HLA-DR的变化,并将细胞涂片行瑞氏-姬姆萨染液染色,油镜下观察摄片。结果与结论：除对照组外,实验各组均得到高表达CD1a及HLA-DR的典型树突状细胞。乌体林斯组CD1a及HLA-DR阳性细胞比例亦明显高于对照组而低于细胞因子组（P〈0.05）,联合组HLA-DR阳性细胞比例高于细胞因子组（P〈0.05）。结果提示,草分支杆菌F.U.36（乌体林斯）不仅能促进脐血树突状细胞体外扩增,还能协同细胞因子促进树突状细胞成熟。

Effects of mycobacterium phlei on proliferation of dendritic cells derived from human umbilical cord blood in vitro

BACKGROUND：The central position of dendritic cells （DCs） has aroused increasing attention due to strong antigen presentation capability in anti-tumor. However,how to obtain enough functional DCs and reports regarding immunomodulator with low toxicity are few. OBJECTIVE：To investigate the effect of mycobacterium phlei F.U.36 （Utilins） on the proliferation and maturity of DCs derived from human umbilical cord blood in vitro. METHODS：The mononuclear cells were isolated from human umbilical cord blood using Ficoll-Hypaque method and cultured with Utilins,cytokine （human recombinant granulocyte/macrophage colonystimulating factor ＋ recombinant human tumor necrosis factor-α ＋ recombinant human interleukin-4）,or combination cytokine ＋ Utilins,respectively. In addition,cells cultured with RPMI-1640 served as controls. Morphological features and growth of DCs were observed by an inverted microscope. The phenotype changes of DCs,such CD1a and HLA-DR,were detected by flow cytometry at 9 days after culture. Moreover,DCs were stained by Wright-Giemsa and observed under oil lens. RESULTS AND CONCLUSION：Typical DCs with high expressions of CD1a and HLA-DR were obviously detected in all experimental groups except the control group. The positive rates of CD1a and HLA-DR in the Utilins group were higher than those in the control group,but lower than the cytokine group （P 0.05）. The HLA-DR positive rate of the combination group was higher than that of the cytokine group （P 0.05）. The results revealed that,Utilins can not only promote the proliferation of DCs derived from human umbilical cord blood in vitro but also cooperate with cytokines to induce the maturity of DCs.