白术多糖对树突状细胞表型及功能成熟的影响

目的：研究白术多糖对人外周血来源的树突状细胞（dendritic cells,DC）表型和功能的影响。方法：应用流式细胞术检测DC表面标志分子HLA-DR、CD86、CD83和CD80的表达及吞噬FITC-dextran的情况,酶联免疫吸附实验检测DC分泌白细胞介素-12（interleukin-12,IL-12）和肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）情况,Western blotting检测DC表面Toll样受体4（Toll-like receptor 4,TLR4）。结果：白术多糖能够促进TLR4的表达,促进DC表面分子HLA-DR、CD86、CD83和CD80的表达,并且呈剂量依赖性,同时还使DC吞噬能力下降;白术多糖能够促进DC分泌IL-12和TNF-α。此外,TLR4抗体可以减少IL-12和TNF-α的产生。结论：白术多糖可以促进人外周血来源的DC表型及功能的成熟。     

卵转铁蛋白对树突状细胞成熟的影响

为考察卵转铁蛋白(OVT)对髓源性树突状细胞(BMDCs)成熟的影响。采用不同浓度OVT单独刺激和脂多糖(LPS)+不同浓度OVT共刺激第6 d小鼠BMDCs 48 h,通过倒置显微镜观察细胞形态,并用流式细胞仪测定各组CD11c+细胞比例以及DCs表面MHC-II,CD80和CD40分子表达量。结果表明,不同浓度OVT组刺激的DCs周围毛刺状突起增加,呈现典型的树突状细胞形态,且上调CD11c+细胞比例以及DCs表面MHC-II、CD80和CD40分子表达量。LPS+不同浓度OVT组中,低浓度(≤25μg/m L)组可提高CD11c+细胞比例,上调MHC-II、CD80和CD40表达量;高浓度(25μg/m L)组则能下调CD11c+细胞比例和DCs表面MHC-II、CD80和CD40表达量。因此,不同浓度OVT均能刺激DCs的成熟;LPS+不同浓度OVT共刺激DCs,能显著提高DCs的成熟度,但呈现剂量依赖型,即低浓度时,两者表现出协同作用,高浓度时两者表现出拮抗作用。     

茶树油调控树突状细胞的表型和功能

本文主要探讨了茶树油对树突状细胞表型和功能的影响。采用茶树油(0.005μL/mL)干预未成熟的树突状细胞48 h后,流式细胞仪检测细胞表型,MTT法检测刺激淋巴细胞增殖能力。结果发现经茶树油干预后,以CD11c设门,树突状细胞高表达H-2Db(48.20%),I-Ab(6.60%)和CD86(41.00%),和空白对照组比较分别达到1.28倍,3.40倍和1.28倍的增长。混合淋巴培养实验发现茶树油能够增强DC刺激淋巴细胞增殖的能力,降低树突状细胞的吞噬功能。初步表明茶树油可以促进树突状细胞的表型和功能成熟。     

茶叶糖蛋白调控树突状细胞对T淋巴细胞增殖和CTL活性的影响

为探讨茶叶糖蛋白(TGP)对小鼠骨髓来源树突状细胞(DCs)表型及功能的影响,采用细胞因子诱导法,以贴壁法获得贴壁单核细胞,添加重组粒细胞-巨噬细胞集落刺激因子(rmGM-CSF)和重组白细胞介素-4(rmIL-4)进行体外诱导培养,倒置显微镜动态观察细胞形态的变化;采用流式细胞术检测DCs的表面标志CD11c和MHC Ⅱ类分子表达;采用MTT法检测TGP对DCs刺激OVA未致敏或致敏淋巴细胞增殖的影响;初步探讨TGP对DCs抗小鼠SP2/0骨髓瘤功能的影响.结果表明,经TGP作用48h后,树突状细胞形态更加典型、成熟;与阴性对照相比,TGP显著促进树突状细胞表面CD11c和MHC Ⅱ的表达;TGP可增强DCs的刺激致敏淋巴细胞增殖的能力,说明DCs诱导免疫应答及抗原提呈功能均增强;与未经抗原负载相比,TGP抗肿瘤机制与促进DCs抗原呈递能力有密切的关系,可提高机体对肿瘤细胞的特异性主动免疫功能,而TGP的干预可促进这一功能的提高.茶叶糖蛋白可以促进树突状细胞表型及功能的成熟.     

菌物多糖对巨噬细胞和树突状细胞的免疫刺激作用及信号通路

菌物多糖能激活巨噬细胞和树突状细胞的成熟,提高表面CD80、CD86和组织相容性抗原(MHC)分子的表达,降低树突状细胞的内吞作用,提高巨噬细胞的吞噬能力;促进各种细胞因子如肿瘤坏死因子-α(TNF-α)、白细胞介素-12(IL-12)和效应分子一氧化氮(NO)、活性氧中间体(ROI)的分泌。菌物多糖发挥作用的信号通路可能是菌物多糖通过与两种细胞表面的Toll样受体(TLR)作用,引发巨噬细胞和树突状细胞胞内丝分裂原活化蛋白激酶(MAPKs)的磷酸化,转录因子活化因子蛋白(AP-1)的磷酸化和核转位,以及促进IκB的降解,使转录因子NF-κB向核转移,来调控核基因的转录和表达,从而对巨噬细胞和树突状细胞发挥免疫刺激作用。     

藏蒲公英多糖纳米乳剂对小鼠外周血T淋巴细胞亚群CD4+、CD8+的影响〖JY。〗〖HTK〗

研究藏蒲公英多糖对小鼠免疫功能的调节作用。采用流式细胞术检测健康小鼠在灌胃0.1 ml质量分数0.85%生理盐水、0.1 ml质量分数1%藏蒲公英多糖水溶液和0.1 ml质量分数1%藏蒲公英多糖纳米乳剂情况下,外周血T淋巴细胞亚群CD4+、CD8+数量的动态变化。结果发现,藏蒲公英多糖和藏蒲公英多糖纳米乳剂均能够显著提高小鼠外周血T淋巴细胞亚群CD4+、CD8+水平,降低T淋巴细胞亚群CD4+、CD8+比值,尤以藏蒲公英多糖纳米乳剂效果最为显著。     

藏蒲公英多糖纳米乳剂对小鼠外周血T淋巴细胞亚群CD4+、CD8+的影响

研究藏蒲公英多糖对小鼠免疫功能的调节作用.采用流式细胞术检测健康小鼠在灌胃0.1 ml质量分数0.85％生理盐水、0.1 ml质量分数1％藏蒲公英多糖水溶液和0.1 ml质量分数1％藏蒲公英多糖纳米乳剂情况下,外周血T淋巴细胞亚群CD4+、CD8+数量的动态变化.结果发现,藏蒲公英多糖和藏蒲公英多糖纳米乳剂均能够显著提高小鼠外周血T淋巴细胞亚群CD4+、CD8+水平,降低T淋巴细胞亚群CD4+、CD8+比值,尤以藏蒲公英多糖纳米乳剂效果最为显著.     

副干酪乳杆菌L9对过敏小鼠淋巴细胞Th1/Th2平衡的调节作用

目的:研究副干酪乳杆菌L9对牛乳β-乳球蛋白(BLG)过敏小鼠淋巴细胞Th1/Th2平衡的影响,探讨L9缓解机体过敏反应的机制。方法 :构建BLG过敏小鼠模型,通过ELISA方法和流式细胞术分析L9对过敏小鼠原代淋巴细胞和骨髓源树突状细胞(BM-DCs)细胞因子分泌及调节性T细胞(Foxp3+Treg)数量的影响。结果:不同剂量的活/热致死L9均可显著提高过敏小鼠淋巴细胞上清中IFN-γ水平,显著降低IL-4含量,减少BLG特异性抗体的产生(P0.05);显著促进BM-DCs细胞上清中调节性细胞因子IL-10、TGF-β的分泌(P0.05),提高过敏小鼠CD4+T淋巴细胞中Foxp3+Treg细胞比例,并且活菌与热致死菌的调节效果相似。结论 :L9能够调节过敏小鼠淋巴细胞的Thl/Th2失衡,这可能与树突状细胞和Foxp3+Treg介导的免疫抑制有关。     

大豆多糖对环磷酰胺抗肿瘤作用的减毒增效机制研究

研究大豆多糖能否减轻环磷酰胺对机体免疫系统和造血系统的影响。以昆明种小鼠为研究对象,腋下接种S180肉瘤,腹腔注射环磷酰胺25mg/kg·d以及大豆多糖50、100、200mg/kg·d。测定S180荷瘤小鼠外周血中白细胞数量,ELISA法检测细胞因子TNF-α的变化,流式细胞仪检测S180荷瘤小鼠T淋巴细胞亚群CD+4/CD+8变化。结果显示:与单独应用环磷酰胺相比,大豆多糖可以提高荷瘤小鼠的外周血中白细胞数量;提高荷瘤小鼠血清中细胞因子TNF-α水平。随大豆多糖给药剂量的升高,CD+4细胞比例变化不明显,CD+8细胞比例降低,CD+4/CD+8升高。故大豆多糖能够通过调节荷瘤小鼠免疫功能而增强环磷酰胺的抗肿瘤作用,并减轻其毒副作用。     

长双歧杆菌BBMN68诱导的树突状细胞对小鼠牛乳β-乳球蛋白过敏的缓解作用

为研究益生菌缓解食物过敏的作用机制,本实验以牛乳β-乳球蛋白(BLG)为过敏原构建小鼠食物过敏模型,灌服长双歧杆菌BBMN68(BBMN68),采用ELISA方法检测小鼠血清及细胞培养上清中抗体和细胞因子含量,流式细胞术分析小鼠体内树突状细胞(DCs)亚型及CD4+CD25+Foxp3+Treg细胞数量的变化。结果表明,BBMN68调节了BLG小鼠体内的Th1/Th2细胞失衡,缓解了过敏反应。与过敏组小鼠相比,BBMN68显著提高了派氏淋巴结DCs中CD103表达(p0.05),并降低了CD86和MHC-II表达(p0.05);提高了派氏淋巴结,肠系膜淋巴结和脾脏中CD4+CD25+Foxp3+Treg细胞数量,分别增加41.91%、71.16%和61.25%。分离BBMN68组小鼠派氏淋巴结的DCs与BLG过敏小鼠的CD4+T细胞共培养,发现Foxp3+Treg细胞比例显著增加,调节性细胞因子TGF-β和IL-10分泌显著增多(p0.05)。以上结果说明BBMN68缓解小鼠牛乳β-乳球蛋白过敏的机制与其调节DCs功能,促进其介导的免疫抑制有关。     

车前子多糖对便秘模型小鼠通便作用的研究

目的:研究车前子多糖对便秘模型小鼠的润肠通便作用。方法:将雄性昆明小鼠随机分为空白组、模型组、阳性对照组和三个剂量的给药组。给药组分别经口给予低、中、高剂量(0.1、0.2、0.4g/kgbw)的车前子多糖;空白组和模型组给予20ml/kgbw的蒸馏水;阳性对照组给予1.0g/kgbw的麻仁丸。连续灌胃8d后,观察各组小鼠的首次排黑便时间、5h内排便粒数,测定粪便含水量和小肠墨汁推进率。结果:车前子多糖能显著缩短首次排黑便时间、增加5h内排便粒数、提高粪便含水量和小肠墨汁推进率。结论:车前子多糖具有润肠通便的作用。     

Kinetics of murine decidual dendritic cells

Dendritic cells (DCs) are professional antigen presenting cells (APC) capable of induction of primary immune responses as well as immunologic tolerance. Myeloid and lymphoid subsets of murine DCs are able to shift cytokine responses of T cells toward Th2 and Th1 profiles respectively. Thus, DCs would be suitable candidates to mediate the balance of maternal immune responses to conception. We analyzed pregnancy-related variations in uterus and splenic DCs in a murine model. C57BL/6-mated Balb/c female mice with vaginal plugs were scarified at early, middle, and late pregnancy. Frozen sections of uterus and spleen at each stage of pregnancy were immunostained with CD11c- and MHC-II-specific antibodies. Two-color immunohistochemistry was also carried out using anti-CD11c and one of the antibodies against CD11b, CD8alpha, CD86, and DEC-205. Using morphometric analysis, the average density of DCs and relative percentage of myeloid (CD11c+, CD11b+) and lymphoid DCs (CD11c+, CD8a+) were determined at each stage. Our results showed that DCs are present throughout the pregnancy in decidua. The average density of decidual DCs at early pregnancy was significantly higher relative to middle and late gestation or to those of endometrial DCs of non-pregnant mice. Interestingly, the average density of decidual and splenic DCs, followed the same variations at different stages of pregnancy. The relative percentage of decidual lymphoid DCs (LDC) was significantly higher at mid-gestation when compared with other stages of pregnancy or non-pregnant mice. Inversely, the frequency of myeloid DCs (MDC) and the MDC/LDC ratio were statistically lower at the middle stage of pregnancy. A majority of decidual DCs expressed MHC-II and CD86. At early pregnancy, DCs were more concentrated subadjacent to the luminal epithelial layers, whereas at mid-or late gestation, DCs were randomly distributed in the stroma and around the epithelium. Mid-pregnancy period was a critical point with regard to splenic DCs kinetics, as both the average density of DCs and the frequency of MDCs decreased significantly when compared with early or late pregnancy, although the relative percentage of splenic LDCs did not change. Our data suggest that the balance of MDC and LDC is finely tuned throughout pregnancy, pointing an eminent immunoregulatory role of DCs in the maintenance of pregnancy.     

Composition analysis and immuno-modulatory effect of okra (Abelmoschus esculentus L.) extract

The aim of this study was to analyse the composition of okra (Abelmoschus esculentus L.) extract and investigate the effect of A. esculentus L. polysaccharides (AE-PS) on the maturation and function of dendritic cells (DCs) derived from rat bone marrow hematopoietic cells (BMHCs) in vitro. BMHC-derived immature DCs (BMHC-imDCs) were extracted from rats and treated with AE-PS. The hydrolysed okra extract contained 0.6% β-1, 3-d-glucan. AE-PS induced the presence of polymorphic nuclei and elongated protrusion in the BHMC-imDCs, indicating DC activation. Treatment with100 μg/mL of AE-PS increased the MHC class II and CD80/86 expression levels by 41% and 42%, respectively. Treated cells had reduced endocytosis activity. The secretion of IL-12 and IFN-γ increased significantly by 120% and 75%, respectively, when treated with 100 μg/mL of AE-PS. Moreover, IL-10 production was reduced by 66%. In conclusion, AE-PS exhibits stimulatory effects on rat dendritic cells and promotes the secretion of T_H1 cytokines.     

嗜酸乳酸杆菌对自主活动受限型应激小鼠肠道黏膜免疫状态的影响

目的：探讨嗜酸乳酸杆菌（Lactobacillus acidophilus,LA）对自主活动受限型应激小鼠肠道黏膜免疫状态的影响。方法：以健康雌性BALB/c小鼠为受试动物,分为常规饲养组（NC组）、常规饲养条件灌胃LA组（NC＋LA组）、应激组（S组）、应激条件灌胃LA组（S＋LA组）,小鼠的LA灌胃剂量为108 CFU/d;应激组小鼠每天被限制自主活动3 h;15 d后取材,采用流式细胞术、酶联免疫吸附（enzyme-linked immunosorbent assay,ELISA）等方法,对肠系膜淋巴结（mesenteric lymph nodes,MLN）中CD4＋T细胞、CD8＋T细胞和CD11c＋树突细胞（CD11c＋ dendritic cell,CD11c＋ DC）比例,结肠组织白细胞介素-10（interleukin-10,IL-10）和白细胞介素-17（interleukin-17,IL-17）水平,以及小肠总分泌型免疫球蛋白A（secreted immunoglobulin A,sIgA）水平进行检测。结果：常规饲养条件下,LA能极显著提高小鼠MLN中CD4＋T细胞比例（P＜0.01）,显著提高MLN中CD11c＋ DC比例、小肠总sIgA水平和结肠组织IL-10水平（P＜0.05）,显著降低结肠组织IL-17水平（P＜0.05）,而对MLN中CD8＋T细胞比例无显著影响（P＞0.05）;应激条件能极显著降低小鼠MLN中CD4＋T细胞比例和CD11c＋ DC比例（P＜0.01）,显著降低CD8＋T细胞比例（P＜0.05）,极显著降低小鼠结肠组织IL-10水平和小肠总sIgA水平（P＜0.01）,极显著提高结肠组织IL-17水平（P＜0.01）;应激条件下,LA能显著提高小鼠MLN中CD4＋T细胞比例和CD11c＋ DC比例（P＜0.05）,显著提高小鼠结肠组织IL-10水平和小肠总sIgA水平（P＜0.05）,并显著降低结肠组织IL-17水平（P＜0.05）,而对小鼠MLN中CD8＋T细胞比例无显著影响（P＞0.05）。结论：给予自主活动受限型应激小鼠LA干预,可提高小鼠MLN中CD4＋T细胞和CD11c＋ DC比例,上调结肠IL-10和小肠总sIgA分泌水平,下调结肠IL-17分泌水平,调节应激小鼠的肠道黏膜免疫状态。     

Genetic variation in bovine mononuclear leukocyte responses to dexamethasone

The objective of this study was to determine whether bovine mononuclear leukocytes exhibit genetic variability prior to and after a glucocorticoid hormone challenge in vivo. Test animals included 60 pedigreed Holstein bulls treated on 3 consecutive days with dexamethasone and 5 untreated control bulls. Eight indicator traits of leukocyte responsiveness to dexamethasone included the percentages of circulating B cells, T cells (CD4, CD8, and workshop cluster 1 molecule expressed by bovine gammadelta T cell), major histocompatibility complex (MHC) I and II expressing cells, and mean expressions of surface MHC I and MHC II on circulating cells. Blood for this work was collected from each test bull 10 times before, during, and after dexamethasone administration, with corresponding samples taken for control bulls. Random regression models with treatment-specific serial correlation were applied to the leukocyte data sets to estimate genetic and nongenetic sources of variation in baseline and recovery aspects of the traits. All traits responded predictably to glucocorticoid challenge. Genetic variation was observed in baseline measurements of all traits, with heritability estimates ranging from 0.21 +/- 0.03 to 0.60 +/- 0.06. Genetic variation in linear recovery from nadir values following dexamethasone administration was significant only for percentage CD4, percentage CD8, and for surface expression of MHC II. The genetic covariance between basal and linear recovery was positive and significant for percentage CD4, percentage CD8, and MHC II expression. The bovine lymphocyte antigen DRB3.2 locus accounted for significant proportions of total variation in percentage MHC II cells and MHC I expression. These results suggest that genetic variability exists for important basal and glucocorticoid-modified phenotypes of bovine mononuclear leukocytes, implying that immunocompetence traits impacted by this stress hormone may be enhanced by genetic selection.     

Negative energy balance does not decrease expression of leukocyte adhesion or antigen-presenting molecules in cattle

Sixteen yearling Holstein steers were fed for 210 or 60% of maintenance requirements to impose positive or negative energy balance, respectively. Blood was collected and analyzed for serum concentration of nonesterified fatty acids (NEFA), and leukocytes were isolated and counted. Isolated leukocytes were then analyzed for expression of the adhesion molecules L-selectin (CD62L), Mac-1 (CD11b and CD18), and major histocompatability complex (MHC) class I and class II molecules with immunostaining and flow cytometric analysis. Negative energy balance increased the concentration of NEFA in serum (P < 0.0001). Expression of CD62L on neutrophils was increased 14% during negative energy balance (P = 0.03). Energy balance did not affect expression of CD62L on any other cell types or expression of CD11b or CD18. Negative energy balance did not affect MHC class I expression but resulted in a small but significant increase in the expression of MHC class II (P = 0.03). The results of this study provide little evidence that nutritionally created negative energy balance impairs expression of CD62L, CD11b, and CD18 or expression of MHC class I or MHC class II molecules by resting bovine blood leukocytes.     

车前子总黄酮的提取工艺优化及体外抗氧化作用研究

通过正交试验,对溶剂法提取车前子总黄酮化合物的工艺进行了优化研究。实验结果表明,各因素对总黄酮提取率的影响程度由大到小依次为:乙醇浓度>温度>提取次数>固液比。最佳提取工艺条件为:乙醇浓度60%,固液比1:30,提取温度90℃,提取3次,每次2h。用DPPH法和邻苯三酚自氧化法评价了该提取物的体外抗氧化能力。结果表明,车前子总黄酮具有较强的体外抗氧化活性。     

Murine CD200+ CK7+ trophoblasts in a poly (I:C)-induced embryo resorption model

Cytokeratin 7 (CK7) is currently regarded as the best marker for trophoblast cells, while CD200 (OX-2), known as 'tolerance signal', plays an important role in normal pregnancy. In this study, the status of CD200 expression was investigated in BALB/c x C57BL/6 and BALB/c x BALB/c mating combinations designed as allogeneic and syngeneic murine models of induced embryo resorption, in which the resorption rate was boosted by an i.p. injection of poly (I:C), a synthetic double-stranded RNA. The percentage of CD200+ cells in the CK7+ cell population (CD200+ CK7+ percentage) and the absolute number of these cells were determined with flow cytometry, using trophoblast cells collected at day 8.5 and day 13.5 of gestation. The potential effect of poly (I:C) on CD200 expression was also evaluated by detecting the CD200+ CK7+ percentage in trophoblast cells incubated in the presence or absence of poly (I:C), in vitro. The distribution pattern of CD200+ cells at the feto-maternal interface was evaluated by immunocytochemical examination. When 10(4) cells were analyzed at day 8.5 of gestation in each case, no significant difference was observed between the poly (I:C)-treated group and the control PBS group either in the CD200+ CK7+ percentage or in the absolute number of these cells. Similar results were observed both in BALB/c x C57BL/6 mice and in BALB/c x BALB/c mice. However, the CD200+ CK7+ percentage was significantly decreased in the poly (I:C)-treated group when evaluated at day 13.5 of gestation. Accordingly, a dramatically elevated rate of embryo resorption was observed at this time point of pregnancy after the administration of poly (I:C). In addition, the CD200+ CK7+ percentage was significantly lower in trophoblast cells incubated with poly (I:C) at a certain concentration, in vitro, while histocytochemical examination showed the CD200+ cells mainly scattered in placental tissue adjacent to the interface of the placenta and uterus. This indicates that sufficient expression of the CD200 molecule on CK7+ cells at the feto-maternal interface may be necessary for the maintenance of embryos during pregnancy in this rodent model, while poly (I:C) administration may increase embryo resorption, at least partially via direct inhibition of CD200 expression on CK7+ cells.     

Regulation of maturation and function of dendritic cells by tea glycoprotein

Tea glycoprotein (TGP) is a glycoconjugate purified from the leaves of green tea (Camellia sinensis). The objective of this study was to evaluate the immunomodulatory effects of TGP on dendritic cells. Murine bone marrow cells were cultured with recombinant mouse (rm)GM-CSF and rmIL-4 for 6?days followed by another 2?days in the presence of TGP or lipopolysaccharide (LPS). The results showed that TGP did not have significant inhibition on cell proliferation and apoptosis. Compared with untreated cells, dendritic cells treated with TGP (50?μg/ml) expressed higher levels of MHC class II molecules and major co-stimulatory molecules such as CD 86, CD 80 and CD 40. However, the endocytic activity was impaired markedly. TGP could enhance the secretion of IL-12p70, but inhibit IL-10 and NO secretion. The activation of antigen-presenting ability and the lymphocyte proliferation of mixed lymphocyte reaction by dendritic cells was also enhanced after treatment with TGP. In addition, an enhanced expression of CCR7 mRNA of dendritic cells treated with TGP was similar to dendritic cells treated with LPS. Taken together, TGP was capable of promoting both phenotypic and functional maturation of murine bone marrow-derived dendritic cells in vitro, which promises the potential clinical application of TGP.