红树林淡紫拟青霉胞外多糖对小鼠DCs吞噬功能的影响

Effects of extracellular polysaccharides from Paecilomyces Lilacinuson on phagocytosis function of mouse bone marrow-derived dendritic cells

目的探讨红树林来源的淡紫拟青霉胞外多糖对小鼠骨髓源性树突细胞(DCs)功能成熟的影响。方法从小鼠骨髓腔中分离获得骨髓细胞,加入重组小鼠粒细胞-巨噬细胞集落刺激因子(rmGM-CSF)、重组小鼠白细胞介素-4(rmIL-4)诱导分化为未成熟DCs,用不同浓度淡紫拟青霉胞外多糖干预,流式细胞术检测DCs的表面标志CD11c、主要组合相容性复合体(MHCⅡ)类分子、CD80、CD86的表达情况及吞噬葡聚糖(FITC-dextran)的能力,反转录-聚合酶链反应(RT-PCR)检测该多糖对DCs Toll样受体(TLR)2mRNA和TLR4mRNA表达的影响。结果经300、400μg/mL多糖作用48h后DCs表面分子CD11c、MHCⅡ类分子、CD80、CD86的表达较空白对照组显著上调(P<0.01);经多糖作用的DCs吞噬FITC-dextran能力下降,尤其是300、400μg/mL的多糖与空白对照组相比作用效果明显(P<0.05);另外,该多糖还可下调DCs TLR2mRNA和TLR4mRNA的表达,尤其经100~400μg/mL多糖处理的DCs下调作用显著,与空白对照组相比差异有统计学意义(P<0.05)。结论淡紫拟青霉胞外多糖可上调小鼠骨髓源性未成熟DCs表面CD11c、MHCⅡ类分子、CD80和CD86的表达,降低其吞噬能力,下调TLR2mRNA和TLR4mRNA的表达,初步表明该多糖可刺激DCs分化成熟。

Objective To investigate the effects of Paecilomyces Lilacinuson extracellular polysaccharides on the phenotypic and function maturity of mouse dendritic ceils. Methods Mononuelear cells were isolated from the mouse bone marrow cavity and added with eytokines for obtaining the recombinant mouse granuloeyte-maerophagoeyte colony stimulating factor（rmGM-CSF）,re- combinant mouse interleukin 4（rmIL-4） was induced to differentiated to immature DCs. Then different concentrations of extraeellu- lar polysaecharides were used to conduct the intervention. The mature DCs surface marker CD11c, major histocompatibility complex II （MHC II ）,CD80, CD86 molecular expression and phagocytosing FITC-dextran ability was detected by the flow eytometry. The effect of the polysaecharides on DCs Toll-like receptor（TLR）2 mRNA and TLR4 mRNA expression was detected by RT-PCR. Re- suits After 400 μg/mL polysaccharides fiction for 48 h, the expression of DCs surface molecules such as CDlle,MHCH ,CD80 and CD86 was significantly up-regulated compared with the blank control group （P〈0.05） ;after the polysaccharides action, the a- bility of DCs phagocytosing FITC-dextran was decreased,especially the effects of 300,400 μg/mL of polysaccharides were more sig- nificant compared with the control group （P〈0.05）. In addition, the polysaecharides could down-regulate the expression of TLR2 mRNA and TLR4 mRNA in DCs, the DCs down--regulation effect after 100-400 μg/mL polysaccharides treatment, the differ- ence compared with the blank control group was statistically significant（P〈0. 05）. Conclusion The extracellular polysaccharides ean up-regulate the expression of DCs surface CD11c, MHC II ,CD80 and CD 86 molecules, decreases the phagocytosis ability and down-regulates the expression of TLR2 mRNA and TLR4 mRNA, which preliminarily indicates that the polysaccharides could stimulate the differentiation and maturation of murine DCs.