粪菌移植对严重烧伤大鼠肠道屏障功能的作用及相关机制

目的探讨粪菌移植(FMT)对严重烧伤大鼠肠道屏障功能的作用及相关机制。 方法按照随机数字表法将36只6～8周龄雄性SD大鼠分为3组：正常组(n＝12)、单纯烧伤组(n＝12)和FMT干预组(n＝12)。单纯烧伤组和FMT干预组大鼠制作30%总体表面积Ⅲ度烫伤模型；正常组大鼠不致伤。单纯烧伤组、FMT干预组大鼠伤后即刻腹腔注射平衡盐溶液40 mL/kg补液复苏。收集正常组大鼠新鲜粪便10 g，制成粪便滤液。伤后1 h，对FMT干预组大鼠进行粪便滤液灌胃(10 mL/kg)，间隔12 h后再次给予相同剂量粪便滤液灌胃；正常组、单纯烧伤组大鼠在相同时相点均给予等量0.9%氯化钠溶液灌胃。分别于伤后24、72 h，取伤后各组大鼠结肠内新鲜粪便各1 mL，采用实时荧光定量-聚合酶链反应检测大鼠肠道菌群属水平，即双歧杆菌、脆弱拟杆菌、乳酸杆菌、大肠杆菌、肠球菌数量；取制备好的大鼠血浆，采用荧光素异硫氰酸酯(FITC)-葡聚糖通透性实验检测3组大鼠肠道通透性；采用酶联免疫吸附试验(ELISA)检测大鼠血清中二胺氧化酶、D-乳酸及白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α、IL-10水平；分别取伤后24、72 h 3组大鼠的末端回肠组织约1 cm，苏木精-伊红染色观察大鼠肠黏膜组织形态结构。数据比较采用单因素方差分析和t检验。 结果(1)3组大鼠在伤后24、72 h双歧杆菌、脆弱拟杆菌、乳酸杆菌、大肠杆菌、肠球菌数量比较，差异均有统计学意义(P<0.05)。伤后24 h，单纯烧伤组大鼠肠道双歧杆菌、脆弱拟杆菌、乳酸杆菌、大肠杆菌、肠球菌数量分别为(2.76±0.15)、(3.27±0.40)、(2.33±0.33)、(7.06±0.49)、(6.42±0.50) LogN/g，FMT干预组大鼠分别为(3.18±0.16)、(4.52±0.58)、(2.92±0.28)、(6.14±0.47)、(5.28±0.43) LogN/g；伤后72 h，单纯烧伤组大鼠肠道双歧杆菌、脆弱拟杆菌、乳酸杆菌、大肠杆菌、肠球菌数量分别为(3.16±0.19)、(3.79±0.42)、(2.64±0.43)、(6.34±0.56)、(5.56±0.61) LogN/g，FMT干预组大鼠分别为(3.53±0.25)、(5.50±0.32)、(3.26±0.39)、(5.37±0.70)、(4.10±0.85) LogN/g，FMT干预组双歧杆菌、脆弱拟杆菌、乳酸杆菌数量均高于单纯烧伤组，大肠杆菌、肠球菌数量均低于单纯烧伤组，差异均有统计学意义(P<0.05)。(2)伤后24 h，正常组、单纯烧伤组和FMT干预组大鼠肠道通透性分别为0.94±0.16、2.39±0.37、1.58±0.33，伤后72 h，正常组、单纯烧伤组和FMT干预组大鼠肠道通透性分别为0.94±0.17、1.88±0.57、1.21±0.24，2个时相点3组间总体比较，差异均有统计学意义(F＝34.092、7.064，P<0.05)；与单纯烧伤组比较，FMT干预组伤后24、72 h大鼠肠道通透性均降低，差异均有统计学意义(t＝ 3.971、2.664，P<0.05)。(3)伤后24、72 h，3组大鼠血清中二胺氧化酶、D-乳酸及IL-6、TNF-α、IL-10水平比较，差异均有统计学意义(P<0.05)；伤后24 h，FMT干预组大鼠血清中二胺氧化酶、D-乳酸分别为(0.93±0.13) U/mL、(3.54±0.78) μmol/L，伤后72 h分别为(0.55±1.15)U/mL、(2.58±0.51)μmol/L，均明显低于单纯烧伤组伤后24 h[(1.28±0.18)U/mL、(4.83±0.57) μmol/L]、伤后72 h[(0.86±0.21)U/mL、(4.13±0.55)μmol/L]，2组比较差异均有统计学意义(P<0.05)。伤后24、72 h，与单纯烧伤组比较，FMT干预组大鼠血清中IL-6、TNF-α水平均降低，IL-10水平均升高，差异均有统计学意义(P<0.05)。(4)伤后24、72 h，正常组大鼠肠黏膜上皮均完整，无炎症细胞浸润；伤后24 h，FMT干预组大鼠肠黏膜绒毛稍变短、排列略紊乱，散在上皮细胞破坏、黏膜脱落，有炎症细胞浸润，较单纯烧伤组相比较肠黏膜损伤减轻。伤后72 h，FMT干预组大鼠肠黏膜上皮基本完整，见少量炎症细胞浸润，肠黏膜修复较单纯烧伤组相比更为明显。 结论严重烧伤大鼠早期可出现肠道菌群紊乱、全身炎症反应加重、肠道屏障功能损害，FMT可以改善肠道菌群失调、抑制炎症反应，起到保护肠道屏障功能的作用。     

胰高血糖素样肽-2对脓毒症大鼠肠黏膜通透性的影响

目的探讨胰高血糖素样肽-2（GLP-2）对脓毒症大鼠肠黏膜通透性的影响。方法采用腹腔注射内毒素（5mg／kg）的方法制作脓毒症模型,根据预实验结果选取病理变化最严重的注射后6h作为实验时间点。成年雄性SD大鼠60只,按数字表法随机分为生理盐水对照组（A组）、脓毒症组（B组）、治疗组（C组）3组,每组20只。A、B、C组分别以生理盐水、脂多糖（LPS）、GLP-2＋LPS腹腔注射于大鼠模型;于注射后6h摘眼球取血,紫外分光光度法检测D-乳酸含量,留取末端回肠组织用免疫组化法检测紧密连接蛋白occludin表达,同时观察肠黏膜病理（HE染色）改变。结果光镜下A组肠黏膜未见明显病理改变;B组肠黏膜明显充血水肿,上皮细胞部分变性、坏死脱落,并有大量炎细胞浸润;C组肠黏膜病理改变较B组明显减轻。A组occludin蛋白沿着细胞膜的顶端呈线状连续分布,B组occludin蛋白分布不均,染色变淡,C组occludin蛋白表达连续性部分恢复,染色变深。B组血液中D-乳酸含量（8．14±0．91）mg／L,高于A组的（3．98±0．68）mg／L和C组的（6．46±0．73）mg／L,差异均有统计学意义（F=144．12,P值均〈0．01）。结论脓毒症大鼠肠黏膜屏障受损,通透性增加;GLP-2可以减轻脓毒症大鼠肠道屏障功能损伤的程度,对脓毒症的肠道损伤有一定治疗作用。     

生长素对5氟尿嘧啶化疗大鼠肠道屏障损伤保护作用

目的观察生长素对5氟尿嘧啶化疗大鼠肠道屏障损伤保护作用。方法将40只雄性SpragueDawley大鼠随机分成4组,每组10只。其中对照组(0.9%生理盐水0.5 mL腹腔注射,每12 h注射1次,连续注射6次)、5FU造模组(5-FU腹腔注射1次+0.9%生理盐水0.5 mL腹腔注射,每12 h 1次,连续6次)、ghrelin阳性对照组(生长素腹腔注射,每12 h 1次,连续6次)和生长素治疗组(5-FU腹腔注射1次+生长素腹腔注射,每12 h 1次,连续6次),采用EDU法测定小肠上皮细胞增殖,Tunnel法检测小肠上皮细胞凋亡,并检测大鼠小肠黏膜形态和损伤指标。结果生长素治疗组大鼠的组织病理、血清DAO和D-乳酸都有优于5-FU组,小肠黏膜细胞凋亡低于5-FU组,而其他均高于5FU组,差异均有统计学意义(P0.01)。结论生长素对5-FU诱导的大鼠小肠黏膜损伤通过减少凋亡增加增生而起保护作用。     

食物过敏动物模型中肝脏的变化

目的　研究食入过敏原后肝脏的变化。方法　试验分为 2组 ,实验组小鼠用卵蛋白 (OVA)致敏 ,OVA(2g/L)经肠道攻击 3h后采血及肝脏 ,用酵素法测定血清中ALT(Alanineaminotransferase) ,并对肝样本进行H&E染色及免疫组织化学染色。结果　实验小鼠血清ALT浓度与对照组比较增高 ,P值有显著差异 (P <0 .0 1 ) ;实验组小鼠肝脏组织H&E染色可见大量炎性细胞浸润及巢状肝细胞坏死 ,免疫组织化学染色显示在OVA致小鼠的肝组织中 ,IL 4及IL 6阳性细胞数明显高于对照组。结论　在食物过敏反应中 ,肝脏也是一个受损害的脏器     

不同剂量桃仁提取物对急性胰腺炎大鼠肠道黏膜屏障功能及免疫功能的作用

目的:研究不同剂量桃仁提取物对急性胰腺炎大鼠肠道黏膜屏障功能及免疫功能的作用。方法:48只大鼠制备SAP模型后随机分为模型对照组、桃仁提取物低剂量、中剂量和高剂量组,每组12只。另取12只大鼠作为假手术组,造模麻醉苏醒即开始干预,桃仁提取物低剂量组、中剂量组和高剂量组分别灌胃给予桃仁提取物0.12、0.248和0.36 g/kg,假手术组及模型组给予等体积蒸馏水灌胃,各组灌胃均1次/6 h,连续4次。给药后24 h应用10%水合氯醛麻醉各组大鼠,打开胸腔和腹腔,腹主动脉分别抽取5 ml血样于EDTA抗凝管和非抗凝管内,分别应用荧光直接标记法和流式细胞仪进行CD4+、CD8+和Treg细胞测定,采用免疫比浊法测定Ig A、Ig G和Ig M,采用EPS-G7底物法测定血清淀粉酶水平,采用酶学分光光度法检测血清D-乳酸水平,采用活性比色法测定血清二胺氧化酶;取小肠组织HE染色后采用光学显微镜进行病理学检查;取小肠组织采用放射免疫法进行s Ig A测定以及采用RT-PCR法进行TLR4和NF-κBp65 mRNA测定。结果:(1)中剂量和高剂量组大鼠血清淀粉酶、D-乳酸和二胺氧化酶水平均较低剂量组大鼠显著降低(P0.01),小肠黏膜s Ig A较低剂量组显著升高(P0.01),并且高剂量组和中剂量组差异具有统计学意义(P0.01);(2)桃仁提取物中剂量和高剂量组血液CD4+、CD4+/CD8+较低剂量组大鼠显著升高(P0.01),CD8+、Treg细胞较低剂量组大鼠显著降低(P0.01),并且高剂量组和中剂量组差异均具有统计学意义(P0.01);(3)桃仁提取物中剂量和高剂量组血清Ig A、Ig G、Ig M较低剂量组大鼠显著升高(P0.01),并且高剂量组和中剂量组差异均具有统计学意义(P0.01);(4)假手术组大鼠小肠黏膜无显著损伤,模型对照组大鼠小肠黏膜显著损伤,低剂量组大鼠小肠黏膜病理情况与模型组基本相似,中剂量和大剂量组大鼠小肠黏膜损伤显著降低;(5)桃仁提取物中剂量和高剂量组小肠组织TLR4和NF-κBp65 mRNA较低剂量组大鼠显著降低(P0.01),并且高剂量组和中剂量组差异均具有统计学意义(P0.01)。结论:桃仁提取物对急性胰腺炎大鼠肠道屏障功能具有保护作用,并且显著改善急性胰腺炎大鼠的免疫功能。     

人参多糖和猪苓多糖对CIA大鼠肠道黏膜免疫细胞功能的影响

目的：观察人参多糖和猪苓多糖对Ⅱ型胶原诱导性关节炎（CIA）大鼠肠道黏膜淋巴细胞功能的影响。方法：采用皮内注射Ⅱ型胶原（COL-Ⅱ）建立CIA大鼠模型，分离模型大鼠PP结淋巴细胞（PPL）、肠道上皮内淋巴细胞（IEL）和固有层淋巴细胞（LPL），分别与不同浓度的人参多糖和猪苓多糖共培养48h后，检测培养上清中TNF-α和IFN-γ含量的变化。结果：与加入RPMI1640培养液的空白对照组比较，不同浓度的人参多糖和猪苓多糖，均可使PPL分泌TNF-α减少，但使IFN-γ的分泌增加；而IEL和LPL分泌TNF-α和IFN-γ的水平均有不同程度的降低。结论：人参多糖和猪苓多糖对CIA大鼠PPL具有不同的免疫调节作用；而对于IEL和LPL，则可导致其免疫活性降低。     

大环内酯类抗生素减轻大鼠油酸性急性肺损伤

目的：观察大鼠油酸性急性肺损伤过程中的肺组织病理改变，并比较大环内酯类抗生素干预前后油酸肺组织病理形态学的变化及肺组织和血清中TNF-α、IL-10含量的变化。方法：48只健康Wistar雄性大鼠随机分为正常对照组：尾静脉注射生理盐水（0.15 mL/kg）；油酸（OA）模型组：尾静脉注射油酸（0.15 mL/kg）；红霉素预防组和阿奇霉素预防组：分别尾静脉注射红霉素针剂（75 mg/kg）和阿奇霉素针剂（15 mg/kg）后1 h时再选另1条尾静脉注射油酸（0.15 mL/kg）；红霉素治疗组和阿奇霉素治疗组：分别尾静脉注射油酸（0.15 mL/kg）后0.5 h时选另1条尾静脉分别注射红霉素针剂（75 mg/kg）和阿奇霉素针剂（15 mg/kg），注射油酸4 h后取材进行各组大鼠肺组织病理形态学评分，计算肺湿干重比，检测肺组织及大鼠血清TNF-α及IL-10含量。结果：油酸致大鼠急性肺损伤时肺组织病理形态学评分值明显高于对照组（P＜0.01），肺湿干重比值高于对照组（P＜0.01），肺组织及血清TNF-α、IL-10含量也明显高于正常对照组（P＜0.01），药物干预组与OA模型组比较，肺组织病理形态学评分值明显降低（P＜0.01），肺湿干重比值明显减小（P＜0.05），肺组织及血清TNF-α含量明显减少（P＜0.01），而肺组织及血清IL-10含量无显著差别（P＞0.05）。结论：大鼠静脉注射油酸可导致肺损伤和全身炎症反应；大环内酯类抗生素红霉素和阿奇霉素可以不同程度抑制TNF-α的产生并减轻油酸性急性肺损伤。     

袖状胃切除术对高脂饮食诱导肥胖大鼠肠道屏障的影响

目的研究袖状胃切除术对高脂饮食诱导肥胖大鼠肠道屏障的影响。方法建立高脂饮食诱导肥胖大鼠模型共30只,随机分为普通饮食组(CD,n=10)、假手术组(SO,n=10)和袖状胃切除组(SG,n=10),术后4周时分别检测24 h尿乳果糖/甘露醇比值(L/M)、门静脉血清内毒素水平和小肠黏膜紧密连接蛋白claudin-1和occludin表达水平。结果术后4周时,SG组大鼠体质量明显低于CD组(P0.001)和SO组(P0.001)。SG组大鼠24 h尿L/M值明显低于CD组(P0.001)和SO组(P0.01)。SG组门静脉血清内毒素水平明显低于CD组(P0.01)和SO组(P0.05)。术后4周时,SG组大鼠小肠黏膜中claudin-1表达水平明显高于CD组(P0.001)和SO组(P0.01),occludin表达水平明显高于CD组(P0.001)和SO组(P0.001)。结论袖状胃切除术可使高脂饮食诱导的肥胖大鼠体质量下降,降低24 h尿L/M值和门静脉血清内毒素水平,提高小肠黏膜中claudin-1和occludin蛋白的表达水平。     

调补肺肾三法对慢性阻塞性肺疾病稳定期大鼠肠道黏膜屏障的影响

目的：探讨调补肺肾三法对慢性阻塞性肺疾病(COPD)稳定期大鼠肠道黏膜屏障的作用。方法：将SPF级SD大鼠随机分为空白(control)组、COPD模型(model)组、补肺健脾(BJ)组、补肺益肾(BY)组、益气滋肾(ZS)组和茶碱(Am)组。于第1～8周采用香烟烟雾暴露联合脂多糖滴注法制备COPD稳定期大鼠模型，第9～12周分别给予各组大鼠灌胃。观察动物一般情况，HE染色观察肺和结肠组织形态学变化，透射电镜下观察结肠组织超微结构变化，TUNEL法测定结肠组织细胞凋亡率，免疫组化染色检测结肠组织occludin (OCLN)和zonula occludens-1(ZO-1)蛋白表达，ELISA法检测血清二胺氧化酶(DAO)、肠脂肪酸结合蛋白(IFABP)和D-乳酸(D-LA)水平。结果：与control组比较，model组大鼠出现进食减少、消瘦和大便溏薄等症状，支气管黏膜皱襞增多明显，肺泡结构紊乱，形成大的气腔，大量炎症细胞浸润；结肠黏膜结构破坏，大量上皮细胞坏死脱落，杯状细胞明显减少，吸收上皮细胞的微绒毛稀疏、缺损，细胞间隙增宽，细胞间连接装置损坏，结肠细胞凋亡率显著升高(P<...     

全颅照射对卡莫司汀通过大鼠血-脑屏障的影响

目的：通过检测卡莫司汀在大鼠脑组织匀浆液中浓度的变化,观察不同剂量X线外照射对血-脑屏障通透性的影响。方法：将50只SD大鼠随机分为0Gy、5Gy、10Gy、15Gy、20Gy组,每组10只,用6MV-X线行单次全颅外照射。照射2周后经尾静脉注射卡莫司汀注射液（62.5mg/kg）,20 min后采集静脉血及脑组织,采用高效液相色谱（HPLC）测定血清和脑组织匀浆液中卡莫司汀的浓度。结果：各组大鼠血清中卡莫司汀浓度比较差异无统计学意义（F=1.44,P〉0.05）,脑组织匀浆液中卡莫司汀浓度随照射剂量的增加呈现逐渐增高趋势,整体各组间比较差异有显著性（F=53.32,P〈0.05）。0Gy、5Gy、10Gy、15Gy组各组间两两比较差异有统计学意义（P〈0.05）,20 Gy组与15Gy组比较差异无统计学意义（P〉0.05）,与其他各组比较,差异有统计学意义（P〈0.05）。结论：：全颅照射可增加血-脑屏障通透性;全脑单次照射〈15 Gy时,随着照射剂量的增加,通透性增加。     

Examination of oral sensitization with ovalbumin in Brown Norway rats and three strains of mice

We studied the conditions needed to sensitize animals to the oral feeding of food allergens, without induction of tolerance, in order to investigate the allergenicity of orally ingested food proteins. Brown Norway (BN) rats were sensitized by daily OVA (ovalbumin)-gavage or by drinking OVA containing water ad libitum and the ASA (active systemic anaphylaxis) response, as the immediate hypersensitivity response to antigen stimulation after oral sensitization, was examined. The oral administration of OVA by gavage produced a higher OVA-specific IgE response and an increase in serum histamine after antigen challenge, as compared to those produced by drinking water. Next, we examined the effect of murine age, the oral feeding technique and the oral feeding dose on sensitization using BALB/c, B10A and ASK mice. Twenty-week-old mice showed the strongest OVA-specific IgE and IgG1 responses and ASA-associated serum histamine contents increased with gavage in the three different age groups of BALB/c mice. Administering 0.1 mg of OVA by gavage daily for 9 weeks appeared to induce a higher response than administering 1 mg of OVA, in terms of OVA-specific IgE and IgG1 antibody responses and ASA responses. Among the three strains of mice, B10A mice exhibited the highest response in terms of OVA-specific IgE and IgG1 antibody and ASA responses. These findings suggested BN rats and B10A mice were suitable models for oral sensitization with antigen protein and that oral sensitization in mice requires low dose, intermittent antigen intakes.     

Intestinal permeability and antigen absorption in rheumatoid arthritis. Effects of acetylsalicylic acid and sodium chromoglycate

Intestinal permeability was measured using cow's milk beta-lactoglobulin absorption (BLG) as a permeability marker in 14 patients with active and inactive rheumatoid arthritis (RA) under three different conditions: after a washout period, after treatment with acetylsalicylic acid (ASA) associated with disodium chromoglycate (DSCG), and with ASA only. No intolerance to cow's milk was present and serum IgE levels were in the normal range in 12 of 14 patients. IgG anti-IgE were present in 7 of 13 patients tested. When off treatment the intestinal permeability to BLG in RA patients was not increased as compared to controls, but we found a significative difference between active and inactive RA. ASA administration strongly increased BLG absorption, not prevented by DSCG pretreatment. In normal controls treated with a single dose of ASA we obtained similar results. Our results suggest that prolonged treatment with nonsteroidal anti-inflammatory drugs induces an increase of food antigen absorption, apparently not related to anaphylaxis mediator release, with possible clinical effects.     

Intestinal anaphylaxis in the rat as a model of food allergy.

An animal model of food allergy has been developed in which some aspects of the allergic response could be quantified and the effects of various drugs evaluated. The change in permeability of the intestinal tract of actively sensitized rats, after oral challenge with the sensitizing antigen, was the parameter measured. Rats were sensitized by injection of egg albumin and B. pertussis vaccine to induce reaginic antibody to egg albumin. Two weeks after sensitization, 125I-labelled bovine serum albumin (125I-labelled BSA) was injected intravenously, followed by oral challenge with egg albumin. Pieces of intestinal tissue were obtained and the amount of 125I-labelled BSA determined in a gamma counter. The amount of 125I-labelled BSA in the intestinal tissue of sensitized and challenged rats regularly showed an increase of greater than 100% above values for control rats.     

Allergen-specific antibody and cytokine responses, mast cell reactivity and intestinal permeability upon oral challenge of sensitized and tolerized mice

Background Food allergy has reached an epidemic level in westernized countries and although central mechanisms have been described, the variability associated with genetic diversity underscores the still unresolved complexity of these disorders. Objective To develop models of food allergy and oral tolerance, both strictly induced by the intestinal route, and to compare antigen‐specific responses. Methods BALB/c mice were mucosally sensitized to ovalbumin (OVA) in the presence of the mucosal adjuvant cholera toxin, or tolerized by intra‐gastric administrations of OVA alone. Antibody titres and cytokines were determined by ELISA, and allergic status was determined through several physiologic parameters including decline in temperature, diarrhoea, mast cell degranulation and intestinal permeability. Results OVA‐specific antibodies (IgE, IgGs and IgA in serum and feces) were produced in sensitized mice exclusively. Upon intra‐gastric challenge with OVA, sensitized mice developed anaphylactic reactions associated with a decline of temperature, diarrhoea, degranulation of mast cells, which were only moderately recruited in the small intestine, and increased intestinal permeability. Cytokines produced by immune cells from sensitized mice included T‐helper type 2 cytokines (IL‐5, IL‐13), but also IL‐10, IFN‐γ and IL‐17. In contrast, all markers of allergy were totally absent in tolerized animals, and yet the latter were protected from subsequent sensitization, demonstrating that oral tolerance took place efficiently. Conclusion This work allows for the first time an appropriate comparison between sensitized and tolerized BALB/c mice towards OVA. It highlights important differences from other models of allergy, and thus questions some of the generally accepted notions of allergic reactions, such as the protective role of IFN‐γ, the importance of antigen‐specific secretory IgA and the role of mucosal mast cells in intestinal anaphylaxis. In addition, it suggests that IL‐17 might be an effector cytokine in food allergy. Finally, it demonstrates that intestinal permeability towards the allergen is increased during challenge. Cite this as: C. Perrier, A.‐C. Thierry, A. Mercenier and B. Corthésy, Clinical & Experimental Allergy, 2010 (40) 153–162.     

双歧杆菌对食物过敏治疗作用的实验研究

目的探讨双歧杆菌对食物过敏的治疗作用。方法 4周龄棕色挪威大鼠(Brown-Norway Rat,BN Rat)构建卵清蛋白(ovalbumin,OVA)致敏动物模型,以OVA 1 mg每天连续灌胃6周,同时分别建立PBS对照组和双歧杆菌治疗组;第6周取血测定血清中OVA特异性IgE(OVA-IgE)水平和IgG(OVA-IgG)水平作为模型评测指标;采用张力换能器测定肠道收缩情况,苏木素-伊红染色(Hematoxylin-Eosin stain,HE)及甲苯胺蓝(Toluidine blue Benzen esulfonic acid,TB)染色观察肠组织病理变化和肠粘膜肥大细胞数目和形态变化。结果第6周时实验组OVA-IgE和OVA-IgG含量显著升高,与对照组相比,OVA-IgE存在显著性差异(P<0.05),OVA-IgG存在极显著差异(P<0.01);经益生菌治疗后,OVA-IgE和OVA-IgG含量显著下降,与实验组相比,存在显著性差异(P<0.05)。双歧杆菌治疗组肠组织收缩较OVA组显著降低,存在显著性差异(P<0.05);HE染色和甲苯胺蓝染色可见双歧杆菌治疗组肠粘膜破坏程度、肠粘膜肥大细胞脱颗粒现象较OVA组缓解。结论 OVA致敏模型和双歧杆菌治疗组模型成功建立,双歧杆菌对食物过敏有较好的治疗作用。     

Intestinal permeability in patients with chronic urticaria-angioedema with and without arthralgia

We evaluated the clinical response to oligoallergenic dietary treatment and the intestinal absorption of a protein antigen, cow milk beta-lactoglobulin (BLG) in 24 patients with chronic urticaria/angioedema syndrome 13 of whom also suffered from joint symptoms. Sixteen patients (77% of those with arthralgia) responded to diet (RD) with marked reduction of symptoms; the others did not respond (NR). Ten (all but one RD with arthralgia) had increased permeability to BLG after oral administration of cow milk. Four with high titers of IgG to BLG showed the highest absorption of BLG and the groups with arthralgia showed higher BLG levels than those without arthralgia. In all cases, specific IgE to cow milk was absent. These data suggest that the symptoms of a subgroup of patients with chronic urticaria, and especially patients with joint complaints that subside with diet, are related to excess intestinal permeability. The measurement of gut permeability to food proteins may be useful to define those who may benefit from dietary restriction.     

Intestinal hypersensitivity reactions in the rat. I. Uptake of intact protein, permeability to sugars and their correlation with mucosal mast-cell activation.

We have confirmed previous observations that intestinal anaphylaxis induced in rats previously sensitized to ovalbumin (OVA) is associated with an increased uptake of an unrelated 'bystander' protein, bovine serum albumin (BSA) fed 1 hr previously. In this study, this enhanced protein uptake was associated with an increased lactulose/rhamnose excretion ratio after administration of these sugars, although there was no correlation between the two measurements. One hour after antigen challenge the serum levels of rat mast-cell protease II (RMCPII), a specific marker for mucosal mast-cell secretion, were significantly higher than both the pre-challenge levels and those of sham-challenged controls (P less than 0.002). There was a significant positive correlation between the serum levels of RMCPII and the lactulose/rhamnose excretion ratios (P less than 0.05), but no such correlation existed between RMCPII and BSA levels in the challenged rats. In other studies the urinary lactulose/rhamnose ratios of rats with cetrimide-induced gut damage were found to be significantly increased, although BSA uptake into the serum remained unaltered. We conclude that there is no simple correlation between gut permeation of low-molecular weight sugars and and the uptake of macromolecular proteins.     

EGF receptor activation during allergic sensitization affects IL‐6‐induced T‐cell influx to airways in a rat model of asthma

EGF receptor (EGFR) is involved in cell differentiation and proliferation in airways and may trigger cytokine production by T cells. We hypothesized that EGFR inhibition at the time of allergic sensitization may affect subsequent immune reactions. Brown Norway rats were sensitized with OVA, received the EGFR tyrosine kinase inhibitor, AG1478 from days 0 to 7 and OVA challenge on day 14. OVA‐specific IgE in serum and cytokines and chemokines in BAL were measured 24 h after challenge. To evaluate effects on airway hyperresponsiveness (AHR), rats were sensitized, treated with AG1478, intranasally challenged, and then AHR was assessed. Furthermore chemotactic activity of BALF for CD4⁺ T cells was examined. The eosinophils, neutrophils and lymphocytes in BAL were increased by OVA and only the lymphocytes were reduced by AG1478. OVA significantly enhanced IL‐6 concentration in BAL, which was inhibited by AG1478. However AHR, OVA‐specific IgE and IL‐4 mRNA expression in CD4⁺ T cells were not affected by AG1478. BALF from OVA‐sensitized/challenged rats induced CD4⁺ T‐cell migration, which was inhibited by both AG1478 treatment in vivo and neutralization of IL‐6 in vitro. EGFR activation during sensitization may affect the subsequent influx of CD4⁺ T cells to airways, mainly mediated through IL‐6.