肝硬化大鼠小肠黏膜形态结构改变与内毒素血症

目的研究药物和胆汁淤积引起的肝硬化大鼠小肠黏膜形态结构改变和血浆内毒素水平。方法分别以硫代乙酰胺(TAA)(n=10)诱导和行胆管结扎术后(BDL)(n=7)的肝硬化大鼠为模型组,另以正常大鼠(n=12)作为正常对照组,分别观察光镜和透射电镜下小肠黏膜的形态,并采用鲎试剂基质显色法测定腹主动脉血浆内毒素含量。结果光镜下观察到模型组肝硬化大鼠小肠肠黏膜绒毛稀疏、萎缩,上皮细胞坏死,黏膜水肿伴有炎性细胞浸润;电镜下观察到模型组大鼠小肠壁超微结构有明显改变,肠黏膜绒毛破坏,减少,变短,倒伏,缺失,肠黏膜紧密间隙增宽,肠黏膜杯状细胞分泌减少,肠黏膜上皮细胞内线粒体和内质网肿胀。正常对照组大鼠的小肠黏膜绒毛形态及超微结构没有明显改变。模型组大鼠的血浆内毒素水平明显高于正常对照组(P<0.01)。结论模型组肝硬化大鼠都存在小肠黏膜结构的改变和内毒素水平的增高,提示肝硬化大鼠小肠黏膜的损伤与肠源性内毒素血症密切相关。     

温阳解毒化瘀颗粒对肠源性内毒素血症大鼠肠黏膜上皮紧密连接的影响

目的：研究温阳解毒化瘀颗粒对肠源性内毒素血症（ IETM ）模型大鼠结肠黏膜上皮紧密连接的影响,探索其抗肝衰竭的作用机制。方法：将大鼠随机分为正常组、模型组、温阳解毒化瘀颗粒（实验组）和对照组4组,采用D-半乳糖胺（D-gal）腹腔注射致肝衰竭ITEM大鼠模型。正常组在腹腔注射生理盐水24h后处死,模型组、实验组、对照组分别于造模后24h、48h、72h各取6只、7只、7只大鼠处死,检测各组肝功能、内毒素、结肠黏膜上皮咬合蛋白（occludin）及肌球蛋白轻链激酶（MLCK）。结果：模型组血清ALT/AST、内毒素、 MLCK表达水平均高于正常组, occludin表达低于模型组（ P＜0.01）;实验组血清ALT/AST、内毒素、 MLCK表达水平均低于模型组, occlu-din表达高于模型组（ P＜0.05）。结论：增强结肠粘膜上皮紧密连接功能,降低内毒素的吸收是温阳解毒化瘀颗粒抗肝衰竭的作用机制之一。     

肠神经胶质细胞对肠黏膜免疫细胞的影响及其在炎症性肠病发生发展中的作用

肠神经胶质细胞是肠道神经系统的重要组成成分,近年来研究发现,除了营养和支持肠神经元,肠神经胶质细胞还与肠道神经-免疫-内分泌网络中的其他成员有着错综复杂的联系,并直接参与整个肠道稳态的调节.其中,肠神经胶质细胞分泌的包括神经营养因子、神经多肽、细胞因子等神经递质是肠神经胶质细胞与肠黏膜免疫细胞联系的重要桥梁,他们与免疫细胞表面的受体特异性结合后引起免疫细胞相应的生化反应.另外,肠神经胶质细胞可能还具有抗原提呈的作用,协同抗原激活肠道免疫反应.目前,肠神经胶质细胞与肠黏膜免疫细胞的关系在炎症性肠病发生发展中的作用尚不完全清楚,本文就这一方面的研究进展进行简单阐述.     

酒精性脂肪肝大鼠肠源性内毒素血症模型的建立

目的：建立酒精性脂肪肝大鼠肠源性内毒素血症模型。方法采用梯度酒精灌胃法早晚两次灌胃,并以10%酒精为饮料,建立大鼠酒精性脂肪肝模型。分别于3w和6w检测肝脂肪变、肝内炎症、肝功能和血清内毒素水平。结果模型组自6w出现显著的肝脂肪变,肝指数（3.6±0.2）、肝脂肪变积分（3.0±0.9）和炎症积分（1.0±0.6）均显著高于同期对照组水平[分别为（3.1±0.1）、（0.0±0.0）和（0.0±0.0）,P＜0.05];在6周时模型动物血浆内毒素、血清D-乳酸、二胺氧化酶和AST分别为（1435.6±52.9）pg/ml、（20.7±5.4）mmol/L、（25.5±2.0）U/L和（124.5±13.2） U/L,较正常组均明显升高[分别为（89.9±10.5）pg/ml、（5.0±1.1）mmol/L、（7.4±1.7）U/L和（40.4±15.2）U/L,P＜0.05]。结论用该方法连续6w成功建立单纯性酒精性脂肪肝肠源性内毒素血症模型。     

通腑颗粒改善犬缺血再灌注状态下实施肠内营养时的小肠功能

目的:研究通腑颗粒(TF)对肠缺血-再灌注(I/ R)状态下实施早期肠内营养(EN)时小肠功能的影响.方法:(?)杂种犬32只随机平均分为EN组、I/R组、I/R EN组和I/R EN TF组,夹闭肠系膜上动脉(SMA)1h后恢复灌流造成肠I/R损伤,复流后4h实施EN.检测小肠腔内压(ICP)、血浆D-木糖含量和二胺氧化酶(DAO)活性评价小肠动力、吸收和屏障功能.结果:肠I/R各组与单纯EN组比较ICP和DAO显著升高(ICP:17.5±1.1kPa,17.6±1.3kPa,17.3±1.5kPa vs 12.3±0.9kPa,均P<0.01;DAO:1.19±0.15U,1.14±0.13U,1.18±0.15U vs 0.68±0.23U,均P<0.01),血浆D-木糖明显降低(2.28±0.23mmol/L,2.31±0.14 mmol/L,2.33±0.10mmol/L vs 3.68±1.05 mmol/L,均P<0.01).肠I/R EN组上述变化最重,肠道不能耐受发生率显著高于I/R组和EN组(87.5% vs 12.5%,0%,P<0.01).EN后1h,通腑颗粒治疗组与I/R EN组相比,血浆ICP和DAO显著降低(ICP:17.1±1.3kPa vs 27.5±1.1kPa,P<0.01;DAO:1.19±0.24 U vs 1.94±0.27U,P<0.01).D-木糖明显升高(2.97±0.21 mmol/L vs 1.07±0.15 mmol/L,P<0.01);肠道不能耐受发生率也显著降低.结论:通腑颗粒能显著改善肠道吸收、动力和屏障功能指标,提高犬I/R时小肠对早期肠内营养的耐受能力.     

梗阻性黄疸对肠黏膜屏障的影响

肠黏膜屏障包括机械屏障、免疫屏障、生物屏障和化学屏障,四者共同维持肠黏膜的正常防御功能。梗阻性黄疸患者引起肠黏膜屏障损伤,导致细菌移位及内毒素血症,后者又加重屏障功能障碍。本文主要就梗阻性黄疸对肠黏膜屏障损伤的机制作一综述。     

谷氨酰胺对饥饿大鼠内毒素移位和肠黏膜免疫功能的影响

目的：探讨饥饿后大鼠肠黏膜形态学结构的变化规律,并动态观察GLN肠内补充对饥饿大鼠内毒素移位和肠黏膜免疫功能的影响.方法：采用饥饿大鼠模型,将90只3月龄♂SD大鼠随机分为正常对照组N：(给予正常饮食n =10)、饥饿组A(n=40)、谷氨酰胺组B(n= 40)3个大组,分别于饥饿后3,5,7,9d,取门静脉血测血浆内毒素的变化,在光镜下观察肠组织的组织形态学改变,利用免疫组化技术检测肠黏膜组织中SIgA的表达和CD4~ 、CD8~ T细胞的数量.结果：A组大鼠饥饿后,3d可见小肠黏膜明显萎缩,绒毛变短、变稀.部分黏膜上皮细胞变性、坏死、脱落,绒毛横径增宽,高度缩短；至饥饿后9d上述变化更加明显.B组在饥饿后3d较同时间点A组肠黏膜损伤有明显的改善,小肠的黏膜厚度、绒毛数量、高度增加,至饥饿后5d基本恢复至N组水平.随着饥饿时间的延长小肠黏膜再次出现黏膜萎缩、绒毛变短、变稀,黏膜上皮细胞变性、坏死、脱落.但明显轻于同时间点的A组.饥饿后各时间点血浆内毒素与N组相比明显升高,A,B组均在饥饿后7d达到高峰,B组在饥饿后3,5,7,9d较A组降低且有非常显著性差异(322.4±65.1,389.4±32.6,464.4±76.6,413.7±67.2EU/L vs 527.1±74.9,546.3±65.7,623.9±85.9,587.5±140.8EU/L,均P＜0.01).与N组比较,A组大鼠肠黏膜SIgA及CD4~ ,CD8~ T细胞数量明显减少,差异有显著性性(P＜0.05,P＜0.01).补充GLN后,SIgA及CD4~ ,CD8~ T细胞数量明显升高,B组与A组比较差异非常显著(P＜0.01).结论：大鼠饥饿后早期确有肠黏膜组织结构受损,发生内毒素移位,同时伴有肠黏膜免疫学屏障受损.早期给予GLN可减轻肠黏膜的受损,明显降低内毒素移位,增强肠黏膜的免疫功能发挥肠黏膜的保护作用.     

通腑颗粒治疗MODS胃肠功能障碍140例

目的:观察通腑颗粒治疗MODS时胃肠功能障碍的临床疗效.方法:采用前瞻性、多种心、临床随机对照研究方法,收集10家北京三级医院ICU病房符合入选标准的140例患者,随机分为A组和B组,分别以加斯清和通腑颗粒治疗.于入选后0h、给药后48h、第7天或死亡前,观察患者肠鸣音及腹部B超肠管积气、积液的情况;抽血并测定血浆内毒素含量、血浆二胺氧化酶(DAO)活性及血浆D-乳酸水平;进行两组胃肠功能评分的比较.结果:治疗第7天加斯清组与通腑颗粒组患者肠鸣音(2.29±1.685次/minvs3.62±1.762次/min,P<0.01),腹部B超积气或积液阳性率(34.4%vs13.5%,P<0.05),血浆内毒素(180±30EU/Lvs111±21EU/L,P<0.05),血浆DAO(4.45±1.67μkat/Lvs3.17±0.83μkat/L,P<0.01),血浆D-乳酸(14.594±2.022mg/Lvs10.49±4.185mg/L,P<0.05),胃肠功能评分(0.407±0.12vs1.32±0.14,P<0.01),各项监测指标差异显著.结论:通腑颗粒能够明显促进MODS时胃肠功能障碍患者肠蠕动,改善肠黏膜屏障功能.     

慢性乙型病毒性肝炎（重度）患者肠黏膜屏障功能的变化及不同干预措施的临床观察

目的 研究慢性乙型病毒性肝炎(重度)患者肠道屏障功能的变化并探讨不同干预方法对其的影响.方法 (1)检测30例正常人和30例慢性乙型病毒性肝炎(重度)患者尿乳果糖、甘露醇排泄率比值(L/M)和血清二胺氧化酶(DAO)的变化,并加以比较.(2)将90例慢性乙型病毒性肝炎(重度)患者随机分为对照组、乳果糖组及谷氨酰胺组(GLN)3组,每组各30例.对照组采用基础治疗,而乳果糖组在基础治疗上加用乳果糖10 g tid,GLN组在基础治疗上加用谷氨酰胺颗粒10 g tid,疗程均为2周.于治疗前后分别测定3组患者的肝功能、内毒素(ET)、肿瘤坏死因子(TNF-α)、DAO、白介素-2(IL-2)、白介素-8(IL-8)、T淋巴细胞亚群、L/M等,并采用协方差分析法加以比较.结果 (1)与正常人相比,慢性乙型病毒性肝炎(重度)患者L/M、DAO水平明显升高(P=0.007及P<0.0001).(2)2周治疗结束后,与对照组相比,乳果糖组治疗后TBIL、ET、TNF-α的变化差异有显著性(P<0.05).与对照组相比,GLN组治疗后ALT、TBIL、TNF-α、ET、IL-2、L/M、DAO的变化差异有显著性(P<0.05).乳果糖组与GLN组相比,治疗后ALT、TBIL、TNF-q、IL-2、L/M的变化差异有显著性(P<0.05).结论 (1)慢性乙型肝炎(重度)患者存在肠黏膜屏障的早期损伤.(2)在常规治疗的基础上加用乳果糖对减轻内毒素血症及炎症反应,降低总胆红素水平有一定的作用,但无法改善肠道屏障损伤.而加用谷氨酰胺则能纠正肠道屏障损伤,减轻内毒素血症与炎症反应,加速肝功能恢复.     

通腑法对大鼠肠源性肺损伤保护作用机制的研究

目的：探讨肿瘤坏死因子(TNF—α)、内毒素(ET)在肠源性肺损伤发病过程中的作用及通腑利肺的作用机制。方法：将40只SD大鼠随机等分为正常对照组、模型组、解扎组及治疗组，每组各10只，采用体外直肠不全结扎法造模。采用动态浊度法检测各组血浆ET水平，放射免疫分析法检测各组血清TNF—α含量，RT—PCR法检测肺组织TNF—αmRNA水平的变化，并将通腑治疗组、解扎组与模型组及正常对照组对照。结果：模型组血浆ET及血清TNF—α水平明显高于正常对照组(P＜0．01)，肺组织TNF—αmRNA表达明显增高(P＜0．01)；通腑法治疗后ET水平、TNF—α含量和TNF—αmRNA表达均低于模型组(P＜0．01)，且肺损伤程度减轻。结论：ET、TNF—α在肠源性肺损伤过程中起重要作用，通腑法对损伤肺组织起保护作用。     

Changes in intestinal mucosal immune barrier in rats with endotoxemia

AIM: To investigate the dysfunction of the immunological barrier of the intestinal mucosa during endotoxemia and to elucidate the potential mechanism of this dysfunction. METHODS: Male Wistar rats were randomly distributed into two groups: control group and lipopolysaccharide (LPS) group. Endotoxemia was induced by a single caudal venous injection of LPS. Animals were sacrificed in batches 2, 6, 12 and 24 h after LPS infusion. The number of microfold (M)-cells, dendritic cells (DCs), CD4~+ T cells, CD8~+ T cells, regulatory T (Tr) cells and IgA~+ B cells in the intestinal mucosa were counted after immunohistochemical staining. Apoptotic lymphocytes were counted after TUNEL staining. The levels of interleukin (IL)-4, interferon (IFN)-γ and forkhead box P3 (Foxp3) in mucosal homogenates were measured by ELISA. The secretory IgA (sIgA) content in the total protein of one milligram of small intestinal mucus was detected using a radioimmunological assay. RESULTS: This research demonstrated that LPS LPSinduced endotoxemia results in small intestinal mucosa injury. The number of M-cells, DCs, CD8~+ T cells, and IgA~+ B cells were decreased while Tr cell and apoptotic lymphocyte numbers were increased significantly. The number of CD4~+ T cells increased in the early stages and then slightly decreased by 24 h. The level of IL-4 significantly increased in the early stages and then reversed by the end of the study period. The level of IFN-γ increased slightly in the early stages and then decreased markedly by the 24 h time point. Level of Foxp3 increased whereas sIgA level decreased. CONCLUSION: Mucosal immune dysfunction forms part of the intestinal barrier injury during endotoxemia. The increased number and function of Tr cells as well as lymphocyte apoptosis result in mucosal immunode- ficiency.     

降气和胃通腑法对肠癌患者术后胃肠功能及免疫功能的影响

目的:观察针灸和中药恢复肠癌术后患者胃肠功能和免疫功能的临床疗效.方法:将肠癌根治性手术后的105例患者随机分成对照组、中药组和针灸组,各35例.对照组给予术后常规处理;中药组给予术后常规处理和术后第1天营养管推入四磨汤口服液20mL,每日3次,治疗10 d;针灸组给予术后常规处理和术后第1天针灸治疗,每日1次,治疗1...     

Dynamic changes and mechanism of intestinal endotoxemia in partially hepatectomized rats

AIM： To explore the mechanism of intestinal endotoxemia （IETM） formation and its changes in partially hepatectomized （PH） rats. METHODS： One-hundred and two adult male Wistar rats were randomly divided into three groups： normal control （NC） group, partially hepatectomized （PH） group and a sham-operated （SO） group. To study the dynamic changes, rats were sacrificed before and at different time points after partial hepatectomy or the sham-operation （ 6 h, 12 h, 24 h, 36 h, 48 h, 72 h, 120 h and 168 h）. NC group was used as Oh time point in observation, namely 0 h group. For each time point indicated, six rats were used in parallel. Endotoxin （ET） and diamine oxidase （DAO） levels were determined in serum using Limulus Lysate test with chromogenic substrate and spectrophotometry. Intestinal mucosa barrier was observed under opticcal or electron microscope. The number and functional state of Kupffer cells （KCs） in the remnant regenerating liver were measured by immunohistochemical staining. RESULTS： Serum ET levels significantly increased during 6-72 h period after PH compared with NC and SO groups, and there were two peak values at 12 and 48 h while serum DAO level significantly increased at 12 and 24 h. There was positive correlation （r = 0.757, P 〈 0.05） between the levels of DAO and ET dynamic changes. The optical examination showed neutrophil margination and superficial necrosis of the villi in the intestinal mucosa during 6-24 h period after PH. The penetrated electron microscope examination showed thatthe gaps between intestinal mucosa cells were increased and the Lanthanum （La） particles were observed among the intestinal mucosa cells during 6-48 h period, The numbers of KCs in the remnant regenerating liver were significantly increased during 24-168 h period after PH, However, the activation of KCs was predominantly observed at 48 h after PH. CONCLUSION： The mechanism of IETM in PH rats might be the injury of intestinal mucosa barrier and the decrease of     

酒精性肝炎小鼠肝肠组织变化与内毒素血症的关系探讨

目的酒精性肝病常伴发肠源性内毒素血症,但两者孰因孰果尚不明确。本研究的目的是探讨肠源性内毒素血症与酒精性肝病的关系。方法 20只C57BL/6小鼠被随机分为对照组和模型组,采用饲喂Lieber-Decarli无酒精和含酒精液体法制备酒精性肝炎模型。6周后取小鼠肝脏和结肠组织进行病理学观察;采用酶联免疫吸附法检测血清内毒素、二胺氧化酶和D乳酸含量;采用高效液相色谱法分析尿中乳果糖和甘露醇含量比值,以动态观察小鼠肠道通透性的变化。结果模型组动物肝细胞明显脂肪变,说明模型制备成功;模型组动物结肠粘膜变薄,萎缩,肠上皮细胞脱落,病理学评分(3.41±0.59)与对照组(2.36±0.43)比,差异有统计学意义(P=0.04);模型组和对照组动物血清内毒素水平分别为0.40±0.07Eu/L和0.14±0.03Eu/L(P=0.02),二胺氧化酶分别为4.17±0.88 U/mL和2.09±0.39U/mL(P=0.03),D乳酸分别为8.53±1.10mg/L和6.58±1.00mg/L(P=0.04),差异均有统计学意义;模型组小鼠1~6周末尿乳果糖/甘露醇(L/M值)排泄率分别是2.28±0.33(P>0.05)、2.55±0.40、2.49±0.18、2.51±0.55、2.46±0.59和2.59±0.44,对照组则分别是2.16±0.30、2.34±0.33、2.27±0.24、2.01±0.27、2.24±0.26和2.17±0.31,后5周两组比,均有显著性差异(P<0.05)。结论肠道通透性的增加早于肝脏损伤,肠道通透性增加引起的内毒素血症是酒精性肝炎的关键诱发因素。     

急性脑缺血后肠道血流灌注和动力的变化及其对肠黏膜屏障的影响

目的 探讨急性脑缺血后大鼠肠黏膜血流灌注和动力变化对肠黏膜屏障的影响. 方法雄性Wistar大鼠64只,随机分为急性脑缺血组(32只)和假手术对照组(32 只),两组大鼠分别按术后6、1 2、24和48 h时相点分为4个业组(每组均为8只),进行肠黏膜血流量、肠道传输系数、门静脉血内毒素水平以及多脏器组织匀浆中标记大肠杆菌移位率的检测. 结果 急性脑缺血组6、1 2、24和48 h时相点肠黏膜血流量分别为(34.5±3.2)PU、(22.7±1.9) PU、(26.2±4.3)PU和(30,5±4.1)PU,与对照组(46.8±5.4)PU、(50.1±3.6)PU、(45.4+4.1)PU、(48.7±7.3)PU比较,明显降低(t=2.650、2.875、2.639、2.507,均P＜0.05);肠道传输系数脑缺血组各时相点分别为0.59±0.07、0.48±0.06、0.50±0.08和0,57±0.04,均低于对照组0.73±0.04、0.75±0.02、0.74±0.06、0.76±0.03(t=2.409、2.758、2.649、2.807,均P＜0.05);脑缺血组损伤后6 h内毒素水平即开始升高,24h达到高峰.各时相点较对照组均明显升高(均P＜0.05).脑缺血组多脏器荧光标记大肠杆菌总检出率(11.4％、18.8％、25.0％、12.5％)明显高于对照组(2.1％、4.2％、2.1％、0％);内毒素水平与肠黏膜血流量和肠道传输系数呈显著相关性(r=-0.861、-0.7 96,均P＜0.05). 结论 急性脑缺血后早期肠黏膜通透性就已增高,而脑损伤大鼠肠黏膜血流、肠运动功能的下降是导致此病理生理变化的重要因素.     

Alterations of intestinal immune function and regulatory effects of L-arginine in experimental severe acute pancreatitis rats

ABM: To discuss the changes of intestinal mucosal immune function in rats with experimental severe acute pancreatitis (SAP) and the regulatory effect of L-arginine. METHODS: Male adult Wistar rats were randomly divided into pancreatitis group, sham-operation group, and L-arginine treatment group. Animals were killed at 24, 48, and 72 h after SAP models were developed and specimens were harvested. Endotoxin concentration in portal vein was determined by limulus endotoxin analysis kit. CD3+, CD4+, CD8+ T lymphocytes in intestinal mucosal lamina propria were examined by immunohistochemistry. Secretory immunoglobulin A (SIgA) in cecum feces was examined by radioimmunoassay. RESULTS: Compared to the control group, plasma endotoxin concentration in the portal vein increased, percentage of CD3+ and CD4+ T lymphocyte subsets in the end of intestinal mucosal lamina propria reduced significantly, CD4+/CD8+ ratio decreased, and SIgA concentrations in cecum feces reduced at 24, 48, and 72 h after SAP developed. Compared to SAP group, the L-arginine treatment group had a lower level of plasma endotoxin concentration in the portal vein, a higher CD3+ and CD4+ T lymphocyte percentage in the end of intestinal mucosal lamina propria, an increased ratio of CD4+/CD8+ and a higher SIgA concentration in cecum feces. CONCLUSION: Intestinal immune suppression occurs in the early stage of SAP rats, which may be the main reason for bacterial and endotoxin translocation. L-arginine can improve the intestinal immunity and reduce bacterial and endotoxin translocation in SAP rats.     

树突细胞在旋毛虫感染免疫中作用的研究进展

旋毛虫病是一种常见的人兽共患寄生虫病,也是一种重要的食源性寄生虫病,严重危害着人体的健康.树突状细胞是固有性免疫细胞的一种,也是宿主肠道黏膜免疫系统最重要的一种抗原呈递细胞,与宿主肠道免疫系统关系密切.近年来有关树突状细胞在寄生虫感染与宿主免疫应答中的作用,尤其在旋毛虫感染与免疫的作用,备受人们的关注.该文就目前国内有关旋毛虫感染后,宿主树突状细胞参与肠黏膜的一系列免疫应答反应和发挥作用的研究进展做一综述.     

Probiotic modulation of dendritic cells co-cultured with intestinal epithelial cells

AIM:To investigate cytokine production and cell surface phenotypes of dendritic cells (DC) in the presence of epithelial cells stimulated by probiotics.METHODS:Mouse DC were cultured alone or together with mouse epithelial cell monolayers in normal or inverted systems and were stimulated with heat-killed probiotic bacteria,Bifidobacterium lactis AD011 (BL),Bifidobacterium bifidum BGN4 (BB),Lactobacillus casei IBS041 (LC),and Lactobacillus acidophilus AD031 (LA),for 12 h.Cytokine levels in the culture supernatants were determined by enzyme-linked immunosorbent assay and phenotypic analysis of DC was investigated by flow cytometry.RESULTS:BB and LC in single-cultured DC increased the expression of I-Ad,CD86 and CD40 (I-Ad,18.51 vs 30.88,46.11;CD86,62.74 vs 92.7,104.12;CD40,0.67 vs 6.39,3.37,P 0.05).All of the experimental probiot-ics increased the production of inflammatory cytokines,interleukin (IL)-6 and tumor necrosis factor (TNF)-α.However,in the normal co-culture systems,LC and LA decreased the expression of I-A d (39.46 vs 30.32,33.26,P 0.05),and none of the experimental probiotics increased the levels of IL-6 or TNF-α.In the inverted coculture systems,LC decreased the expression of CD40 (1.36 vs-2.27,P 0.05),and all of the experimental probiotics decreased the levels of IL-6.In addition,BL increased the production of IL-10 (103.8 vs 166.0,P 0.05) and LC and LA increased transforming growth factor-β secretion (235.9 vs 618.9,607.6,P 0.05).CONCLUSION:These results suggest that specific probiotic strains exert differential immune modulation mediated by the interaction of dendritic cells and epithelial cells in the homeostasis of gastrointestinal tract.     

慢性乙型肝炎患者肠源性内毒素血症与树突状细胞表型及功能的关系

目的 探讨慢性乙型肝炎(CHB)患者树突状细胞(DC)与肠源性内毒素血症(IETM)的关系.方法 CHB患者80例,健康对照者21例,采集外周血,测定血浆内毒素含量、ALT、TBil.根据血浆内毒素水平,将患者分为内毒素阳性组和阴性组.同时用重组人粒细胞巨噬细胞集落刺激因子、重组人白细胞介素-4、酪氨酸激酶受体3配体和TNF-a体外诱导、培养CHB患者DC,采用流式细胞仪检测DC表型,混合淋巴细胞反应检测DC刺激T淋巴细胞的能力,用ELISA检测DC分泌细胞因子的水平.多组间比较采用单因素方差分析.结果 CHB患者DC表达CD83、CD80、CD86和人类白细胞抗原(HLA)-DR分子的水平及诱导同种异体混合T淋巴细胞增殖的能力均明显低于健康对照组.内毒素阳性组患者表达CD83、CD80、CD86、HLA-DR水平及诱导T淋巴细胞增殖的能力分别为(8.25±3.63)%、(10.63±4.52)%、(36.61±16.16)%、(61.65±14.33)%、0.812±0.311,明显低于内毒素阴性组的(11.39±4.35)%、(13.56±5.13)%、(45.90±15.35)%、(70.35±18.89)%、1.153±0.324(F=5.123、4.213、3.714、3.323、3.125,均P＜0.05).培养至第9天,CHB患者DC分泌IL-12和IFN-γ分别为(16.99±6.74)pg/mL和(10.52±4.19)pg/mL,明显低于健康者的(44.51±14.56)pg/mL和(17.94±5.86)pg/mL.内毒素阳性组患者IL-12水平为(13.14±5.71)pg/mL,明显低于内毒素阴性组的(20.98±9.03)pg/mL(F=3.225,P=0.016).IFN-γ水平在内毒素阳性组为(9.46±3.24)pg/mL,与阴性组的(11.54±5.20)pg/mL比较,差异无统计学意义(F=2.003,P=0.076).结论 IETM是导致CHB患者体内DC功能异常的原因之一.

Abstract：

Objective To investigate the relationship between dendritic cell (DC)and intestinal endotoxemia in patients with chronic hepatitis B (CHB).Methods Peripheral blood were collected from CHB patients (n = 80)and healthy controls (n = 21 ).Plasma endotoxin (ET)levels,liver function (alanine transaminase,total bilirubin)were detected.According to plasma ET concentration,all CHB patients were divided into two groups:ET positive and ET negative.The peripheral blood mononuclear cells (PBMCs)were isolated and then cultured with recombinant human granulocyte-macrophage colony-stimulating factor ( rhGM-CSF),recombinant human interleukin-4 ( rhIL-4 ),FMS-related tyrosine kinase 3 ligand (Flt3L)and tumor necrosis factor-alpha (TNF-α)to derive DC.The phenotypic patterns were characterized by flow cytometry.The proliferation of T lymphocytes was evaluated with mixed leukocytes reaction (MLR)and the levels of IL-12 and interferon-γ (IFN-γ)produced by DC were analyzed with enzyme-linked immunosorbent assay (ELISA).Comparisons among the two groups and healthy control group were done by single factor analysis of variance.Results Compared to healthy controls,the expressions of CD83,CD80,CD86,human leucocyte antigen (HLA)-DR and the proliferation of allogeneic T lymphocytes by DC were all significantly reduced in CHB patient groups.The expressions of CD83,CD80,CD86,HLA-DR and the activation of proliferation in ET positive subjects were lower than those in ET negative subjects [CD83 (8.25±3.63)% vs(11.39±4.35)% ,CD80 (10.63±4.52)% vs (13.56±5.13)%,CD86 (36.61±16.16)% vs (45.90±15.35)%,HLA-DR (61.65±14.33)% vs (70.35±18.89)%,the activation of proliferation0.812±0.311 vs 1.153±0.324; F=5.123,4.213,3.714,3.323 and 3.125,respectively; all P＜0.05].After cultured for 9 days,the secretions of IL-12 and IFN-γ by DC were significantly lower in CHB patients than in healthy controls [IL-12 (16.99± 6.74)pg/mL vs (44.51±14.56)pg/mL,IFN-γ (10.52±4.19)pg/mL vs (17.94±5.86)pg/mL].The level of IL-12 in the ET positive group was significantly lower than that ET negative group [( 13.14 ±5.71)pg/mL vs (20.98 ± 9.03)pg/mL; F= 3.225,P = 0.016].The level of IFN-γ was not different between two groups [(9.46 ± 3.24)pg/mL vs (11.54 ± 5.20)pg/mL; F = 2.003,P =0.076].Conclusion The intestinal endotoxemia may play a role in DC dysfunction in CHB patients.