抗重组VacA IgY体内抗幽门螺杆菌感染的实验研究

目的在构建H.pylori的基因工程菌pQE30-v-DH5a的基础上,诱导表达VacA重组蛋白,以此为抗原,制备抗VacA的蛋黄抗体（VacA IgY）。通过小鼠口服试验,证实VacA IgY治疗H.pylori感染的作用,为进一步制备抗H．pylori感染的IgY制剂提供实验依据。方法用重组H.pylori VacA蛋白免疫母鸡,水稀释结合氯仿有机沉淀法提取IgY,ELISA法测定其针对VacA的效价。建立H.pylori感染的Balb／c小鼠动物模型,治疗组在小鼠灌喂菌液后灌喂不同剂量的VacA IgY。以H.pylori培养和病理切片观察胃黏膜H.pylori定植和炎症反应程度。结果制备了高效价的IgY（1：12800）。动物实验阳性对照组H.pylori的总感染率为70．4％,12周后的感染率为88．9％。治疗组的感染率与同期阳性对照组相似,胃黏膜的炎症反应程度比阳性对照组弱,随IgY剂量的增加,炎症减弱明显,IgY剂量为4mg／ml时,能达到较理想的治疗效果。结论成功制备了高效价的特异性VacA IgV,小鼠体内实验证实了口服VacA IgY具有治疗H.pylori感染的作用,可用于制备口服制剂。     

幽门螺杆菌(SS1)感染及其胃炎的小鼠模型

目的 :建立感染幽门螺杆菌 (Helicobacterpylori,H pylori)SS1株BALB/c小鼠感染模型 ,研究H pylori胃内定植及胃黏膜病理变化。 方法 :BALB/c小鼠胃内分别接种体外培养的H pyloriSS1株 (实验组 )或PBS(对照组 ) ,组织学方法评价H pylori定植及胃黏膜病理变化。结果 :所有对照组小鼠胃组织未见H pylori定植 ,胃组织也未见明显的炎症反应 ;而所有实验组小鼠在感染H pylori 12周后 ,胃黏膜表面的黏液层及胃小凹顶端可见大量H pylori,胃体及胃窦交界处、胃体及胃底交界处最多 ;胃组织可见到不同程度的炎性反应 ,感染H pylori 2 4周后 ,胃组织炎性反应加重。结论 :用胃内接种方法建立了小鼠H pylori感染及其相关性胃炎的模型。     

H.pylori对MGs胃黏膜Cx32、Cx43及相关转录因子表达的影响

目的观察幽门螺杆菌(Helicobacter pylori,H.pylori)对蒙古沙土鼠(Mongolian gerbils,MGs)胃黏膜Cx32、Cx43和转录因子GATA-3、AP-4、PBX-1、C/EBPβ表达的影响及其相关性,探讨H.pylori致癌的机制。方法实验组采用经胃镜及病理确诊的胃癌患者胃黏膜分离的H.pylori对36只MGs灌胃,对照组5只用灭菌PBS灌胃;分批处死,观察H.pylori灌胃后第4、24、48、72周MGs H.pylori定植和胃黏膜病变情况,及Cx32、Cx43和转录因子表达变化。结果实验组H.pylori定植率为80.0%,灌胃后第4、24周MGs胃黏膜肉眼见充血水肿或糜烂、出血,HE染色呈不同程度慢性非萎缩性胃炎(NAG),48周后6例肉眼见胃黏膜变薄、颜色灰暗,HE染色4例慢性萎缩性胃炎(CAG)、2例肠化(IM),对照组无H.pylori定植,胃黏膜肉眼及HE染色无明显异常;实验组较对照组MGs胃组织Cx32、Cx43表达显著下降,转录因子GATA-3、AP-4、PBX-1、C/EBPβ表达显著升高(P0.05),其中有胃癌前病变(CAG和IM)者较NAG者改变明显(P0.05);Cx32、Cx43与转录因子表达呈负相关(-1r0,P0.05)。结论 H.pylori感染上调MGs胃黏膜转录因子GATA-3、AP-4、PBX-1和C/EBPβ表达,下调Cx32、Cx43表达,可能与胃癌发生有关。     

金山西部地区5~7岁儿童H.pylori感染调查及与胃蛋白酶原相关性分析

目的了解金山西部地区5~7岁健康儿童幽门螺杆菌(H.pylori)感染情况,并探讨其与胃蛋白酶原(PG)的相关性。方法选取2019年3-5月金山地区5~7岁健康儿童共464例,分析不同年龄及性别幼儿H.pylori感染、胃蛋白酶原Ⅰ(PGⅠ)、胃蛋白酶原Ⅱ(PGⅡ)水平以及PGⅠ/PGⅡ比值的差异,采用Spearman相关性分析H.pylori感染与PGⅠ、PGⅡ水平和PGⅠ/PGⅡ的相关性。结果5~7岁儿童H.pylori阳性率达11.96%,5岁组、6岁组、7岁组儿童H.pylori阳性率分别为10.07%、12.96%、13.73%,阳性率逐年升高。不同年龄和性别幼儿的PGⅠ、PGⅡ水平和PGⅠ/PGⅡ间差异有统计学意义(P<0.05)。H.pylori是否感染与PGⅠ/PGⅡ呈显著正相关,与PGⅠ/PGⅡ呈显著负相关(P<0.05)。结论本地区5~7岁儿童H.pylori感染率相对较低且有着自身的特点,而且H.pylori感染与血清PG水平的关系密切,未来应加强对幼儿H.pylori感染与血清PG 水平的监测及防治。     

探讨接种时间和剂量对小鼠肺炎支原体肺炎模型建立的影响

目的 用不同时间和剂量建立BALB/c小鼠的肺炎支原体肺部感染模型,探索小鼠急性肺炎支原体感染的过程.方法 BALB/c小鼠随机分为Ⅰ、Ⅱ两组,Ⅰ组在0、1、2 d滴鼻接种肺炎支原体菌液3次,Ⅱ组在0 d滴鼻接种小剂量肺炎支原体菌液1次后于8、9 d再接种和Ⅰ组相同的肺炎支原体菌液2次,均设立不同剂量、批次的生理盐水对照组.全部实验动物在3～18 d内分批处死.所有小鼠均取肺组织做病理切片.以组织病理学评分来确定小鼠的肺部炎症反应程度.取肺组织匀浆及肺泡灌洗液(BALF)进行肺炎支原体培养做病原学检测.结果 接种后实验动物全部存活无死亡.实验组动物均出现不同程度的肺炎支原体肺炎样病理改变,组织病理学评分为1.5～14.3分,分别于第5、6天和第11天达到最高,平均分为4.9分;Ⅰ组实验组动物多呈轻、中度改变,Ⅱ组实验组动物多呈中、重度改变.所有实验组动物肺组织匀浆及BALF的肺炎支原体培养在接种后1月内先后出现阳性结果.对照组动物未出现明显肺部炎症改变,组织病理学评分为0～1分,肺炎支原体培养为阴性.结论 成功建立BALB/c小鼠的肺部肺炎支原体感染模型;组织病理学评分方法可用以评价肺部炎症反应的严重程度;不同接种时间和剂量所致的病变程度不同.     

溃疡性结肠炎患者肠道菌群失调与H. pylori感染和DAI评分及免疫球蛋白水平的相关性

目的 探讨溃疡性结肠炎（UC）患者肠道菌群失调与幽门螺杆菌（H. pylori）感染、疾病活动指数（DAI）评分和免疫球蛋白的相关性。方法 选取2019年6月至2021年6月在我院确诊的97例UC患者作为观察组,根据肠道菌群失调程度将患者分为Ⅰ度组（34例）、Ⅱ度组（38例）、Ⅲ组（25例）,另同期随机选取在我院进行健康体检的健康者97例作为对照组。采用微生物鉴定系统检测并比较所有患者肠道肠球菌、双歧杆菌、乳杆菌及大肠埃希菌的数量;采用14C尿素呼气试验检查并比较所有患者H. pylori感染情况;采用DAI评分比较所有患者的疾病活动情况;采用免疫散射比浊法检测患者的免疫球蛋白（IgA、IgG、IgM）水平;采用Pearson相关性分析研究UC患者肠道菌群与DAI评分及免疫球蛋白的关系。结果 Ⅰ度组和Ⅱ度组患者H. pylori阳性率分别为50.00%和31.58%,均显著高于Ⅲ度组的20.00%（χ2=6.026, P=0.049）。Ⅰ度组、Ⅱ度组、Ⅲ度组患者肠道肠球菌、大肠埃希菌数量多于对照组,双歧杆菌、乳杆菌的数量少于对照组（均P<0.05）,且相较于Ⅰ度组,Ⅱ度组、Ⅲ度组...     

近交系小鼠线粒体DNA多态性的研究

目的　分析BALB/c等八个近交系小鼠线粒体DNA(mtDNA)的多态性 ,探讨近交系小鼠的遗传监测方法。方法　PCR -RFLP技术 ,即PCR技术结合限制性内切酶片段长度多态分析 (restrictionfragmentlengthPolymorphism ,RFLP)。结果　mtDNAD -Loop、tR NAIle GIN Met、ND3基因片段经HaeⅢ、HinfⅠ、EcoRV、HindⅢ、HpaⅠ、BamHⅠ、ApaⅠ、NdeⅡ、XhoⅠ、XbaⅠ、AluⅠ、RsaⅠ、StuⅠ、DraⅠ、AvaⅠ、HaeⅡ 16种内切酶分别消化后 ,BALB/c、C3H、C57BL/ 6J、T739、DBA/ 2、TA2、6 15、BALB/c -nu/nu等小鼠均表现出相同的酶切格局 ,未发现多态性。结论　BALB/c、C3H、C57BL/ 6J、T739、DBA/ 2、TA2、6 15、BALB/c -nu/nu等近交系小鼠遗传背景较为狭窄 ,不同品系小鼠间遗传背景的差异远远低于动物种属间的差异     

小鼠萎缩性胃炎模型的构建及与血清胃泌素 17、白介素 8的关系

目的建立小鼠慢性萎缩性胃炎(CAG)模型;用此模型探讨胃泌素-17(gastrin-17,G-17)及白介素-8(IL-8)在CAG诊断和病程进展中的应用价值。方法选取SPF级、体质量22～24 g、5～7周龄雄性C57BL/6小鼠40只,随机分为阴性对照组(A组,超纯水)、高盐组(B组,1.8%NaCl溶液)、H.pylori组(C组,H.pylori悉尼菌株SS1)和高盐+H.pylori组(D组,1.8%NaCl溶液+SS1菌株)4组,每组10只,分别对各组小鼠进行灌胃处理。于第16周和第24周每组分别处死5只小鼠,通过免疫组化观察H.pylori情况、胃黏膜病理组织学变化,酶联免疫吸附法(ELISA)检测小鼠血清G-17和IL-8的表达水平。结果灌胃处理16周可观察到B、D两组小鼠CAG造模成功,G-17表达水平差异无统计学意义(χ~2=6.591,P0.05);C、D两组小鼠IL-8表达水平较A、B两组明显升高(F=25.241,P0.05)。24周后可观察到B、C、D三个实验组均CAG造模成功:B、D组小鼠G-17表达水平较A组明显降低(χ~2=15.006,P0.05),C组G-17水平与A组差异无统计学意义(Z=-1.681,P0.05);H.pylori处理组(C、D)小鼠的IL-8水平明显升高(F=31.941,P0.05)。结论高盐饮食和胃黏膜H.pylori定植均可成功构建C57BL/6小鼠CAG模型,且高盐饮食可加快该模型的建立;血清G-17表达水平与CAG病情严重程度呈负相关,而IL-8的表达水平与是否H.pylori感染有关。     

抗坏血酸对幽门螺杆菌相关萎缩性胃炎小鼠的干预

目的研究不同浓度抗坏血酸(ascorbic acid)溶液对幽门螺杆菌(Helicobacter pylori,H.pylori)相关萎缩性胃炎小鼠模型的作用。方法将C57BL/6小鼠随机分为5组,每组10只。组1为空白对照组,余4组小鼠用幽门螺杆菌悉尼菌株(Helicobacter pylori-Sydney strain 1,H.pylori-SS1)感染2周,快速尿素酶法和免疫组织化学法检测H.pylori-SS1的定植;组3、组4和组5小鼠分别给予抗坏血酸低倍剂量(0.1 g/L)、中倍剂量(0.5 g/L)和高倍剂量(1.0 g/L)灌胃22周。灌胃结束后,处死所有小鼠取胃组织和血清,H&E染色观察组织学变化,ELISA检测血清胃泌素(gastrin)和白介素8(IL-8)水平。结果与H.pylori组相比,抗坏血酸干预组胃组织萎缩程度减轻、血清胃泌素水平升高、炎症因子水平降低(组2 vs组3:F=21.730,P=0.029;组2 vs组3:F=42.781,P=0.015;组2 vs组3:F=35.720,P=0.021),中倍剂量组较低倍剂量组有更显著的作用(组3 vs组4:F=21.730,P=0.041;组3 vs组4:F=42.781,P=0.034;组3 vs组4:F=35.720,P=0.043),但高倍剂量组与中倍剂量组差异无统计学意义(组4 vs组5:F=21.730,P=0.125;组4 vs组5:F=42.781,P=0.391;组4 vs组5:F=35.720,P=0.450)。结论抗坏血酸干预可减轻小鼠H.pylori相关萎缩性胃炎症状,高剂量抗坏血酸与中低剂量比无显著差异。     

O157：H7大肠杆菌感染动物模型的建立

为了建立一个适合于O157:H7大肠杆菌疫苗及药物评价的稳定有效、经济易行的动物模型,通过筛选获得耐链霉素的O157菌,并用其在BALB/c小鼠体内传代获得对小鼠的适应株O157-Sr1.6只6周龄雄性BALB/c小鼠用链霉素溶液预处理过后,以O157-Sr1培养菌液经口感染.     

Development of a BALB/c mouse model of Helicobacter pylori infection with fresh and frozen bacteria

An experimental model for H. pylori infection was established by intragastrically challenging BALB/c mice with 1 ml (10(8) CFU/ml) of suspension for two consecutive days. Animals were divided into three groups. GA: mice inoculated with fresh bacteria; GB: mice inoculated with frozen bacteria, and GC: mice inoculated with brucella broth (control group). Animals were killed at 7, 14, 21, 28, 35 and 60 days pi and fragments of stomach and duodenum were collected, paraffin embedded and stained by hematoxylin-eosin and Giemsa. The results showed that challenged mice exhibited mild duodenitis and gastritis. In group GA, infiltration in the duodenum was lymphoplasmacytic until day 35; in group GB, it was lymphomonocytic for 60 days pi. In the stomach, H. pylori induced lymphomonocytic infiltration that was present from days 7 to 60 in group GA. In group GB, it was only present from days 14 to 35. In conclusion, our data suggested that freezing altered pathogenic properties of H. pylori and probably inhibited expression of bacterial antigens and consequently the establishment and maintenance of infection. Although the animals developed mild duodenitis and gastritis, the BALB/c mouse is not susceptible to developing peptic ulcers during H. pylori infection.     

近交系小鼠移植性肝癌模型建立及对比分析

目的：通过对比分析选择建立原位移植性肝癌模型的最佳小鼠品系。方法选取C57、C3H和BALB／c各10只小鼠分别作为模型组Ⅰ、模型组Ⅱ和模型组Ⅲ,沿腹中线开腹后将H22细胞接种到各模型组小鼠肝脏实质内。于注射后第15天剖腹探查,观察各组成瘤率,测量腹水量和肿瘤体积,并进行肿瘤病理学分析。结果三组小鼠存活率均为100％,15天后三组小鼠均产生腹水,但三组腹水量之间不具有统计学差异。模型组Ⅰ小鼠肝癌移植成功率为100％,高于模型组Ⅱ的60％和模型组Ⅲ的30％。模型组Ⅰ小鼠肝脏肿瘤全部为大块紧实灰白色病灶,其肿瘤平均体积显著大于模型组Ⅱ和模型组Ⅲ（ P＜0.05）。病理结果证实三组小鼠肝脏的灰白色病灶均为原位肝细胞癌。结论 C57小鼠是复制原位移植性肝癌模型较为理想的实验动物,为今后研究原位肝癌的发病机制提供良好的实验平台。     

Importance of the host genetic background on immune responses to Helicobacter pylori infection and therapeutic vaccine efficacy

In order to investigate the role of host factors in Helicobacter pylori infection and immunity, two different strains of inbred mice, C57BL/6 and BALB/c, were infected with a standard H. pylori strain, SS1. A month later, infected mice were immunized orally with whole-cell lysates of H. pylori SS1 and cholera toxin on days 1, 3, 6, 30, and 54. Ten days after the last immunization, mice were sacrificed and the stomach was collected to assess H. pylori colonization density by quantitative culture. H. pylori SS1 colonization was significantly greater in C57BL/6 than in BALB/c (P<0.02 and P<0.003 at 2 and 13 weeks post-inoculation, respectively). Colonization in C57BL/6 persisted at equivalent levels for 13 weeks but the colonization density in BALB/c decreased significantly during this period. In contrast to the pattern of bacterial colonization, antibody responses following H. pylori SS1 infection were greater in BALB/c than in C57BL/6, suggesting that host factors may modulate the immune responses to H. pylori infection. Following therapeutic immunization, H. pylori colonization in BALB/c mice was also significantly reduced (P<0.03), while no significant differences in bacterial density were observed in C57BL/6. These observations collectively demonstrate the great importance of host factors in H. pylori infection and the development of effective immune responses.     

幽门螺杆菌感染和抗菌治疗对食道下端菌群的影响

目的通过小鼠动物模型,探讨幽门螺杆菌（Helicobacter pylori,H.pylori）感染和用抗生素抗H.pylori治疗对食道下端菌群的影响,分析其与食道下端疾病发生的关系。方法将45只Balb/c小鼠随机均分为阴性对照组,感染组和治疗组。感染组和治疗组通过灌喂H.pylori建立动物感染模型,治疗组再灌喂奥美拉唑,氨苄青霉素,克拉霉素根除H.pylori。三组小鼠均在用抗生素处理后同时处死,取食道下端组织提取细菌的DNA,以原核生物16S rDNA V6区通用引物采用聚合酶链发应-变性梯度凝胶技术（PCR-DGGE）检测,用Quantity One1-DAnalysis software对DGGE图谱进行菌群结构分析,并将DGGE图谱上的组间差异条带用16S rDNA V6区引物分别扩增后,DNA测序,BLAST比对鉴定。结果成功制备了小鼠幽门螺杆菌感染模型,用抗生素有效根除了H.pylori感染。小鼠食道下端DGGE指纹图谱分析显示,各组间条带数量比较差异均有统计学意义（P〈0.05）,多样性指数、丰富度指数差异有统计学意义（0.05〉P〉0.001）,均匀度指数差异无统计学意义（P〉0.05）。菌群聚类分析能很好地在相似性进化树中分开,主成分分析不同组的菌群分别聚集在不同的位置,BLAST比对分析对照组,感染组具有特有细菌。结论食道下端定植着由大量细菌构成的较稳定的菌群,H.pylori感染与治疗后菌群结构有明显变化。     

Acute inflammatory response in the stomach of BALB/c mice challenged with coccoidal Helicobacter pylori

An experimental murine model was used to verify the viability and pathogenicity of coccoid Helicobacter pylori. For this purpose, 27 BALB/c mice were inoculated intragastrically with 1 ml broth culture (10(8)organisms/ml) of a coccoid H. pylori clinical isolate. The animals were divided into two groups. Nine were infected on a one-time basis (GA1) and 18 were infected on two consecutive days (GA2). Other 27 mice were inoculated with Brucella broth and divided in the same way; they composed the control group. Mice were killed at 2, 3, 7, 14 and 21 days post inoculation (pi). Fragments of stomach and duodenum were collected, fixed with 12% formalin and stained by hematoxilin-eosin and Giemsa for histopathological examination. Until the 14th()day, only reinfected mice had mild-to-moderate inflammatory infiltrate in the stomach. The infiltration was predominantly lymphomonocytic, although plasma cells and eosinophils could be seen. However, at 21st day, severe eosinophilic infiltration was present in the lamina propria and submucosa of gastric corpus. In subgroup GA1, animals presented lymphomonocytic infiltration in the stomach from 14th()day pi. Our results showed that coccoid H. pylori was able to induce an acute inflammatory response in stomach of reinfected mice since the initial periods of infection.     

不同品系小鼠感染甲型流感病毒肺小血管内血栓形成

目的本实验旨在观察不同品系小鼠感染甲型流感病毒后肺组织内血栓形成的情况。方法使用H1N1病毒A/California/7/2009（CA7）株和H3N2病毒A/Brisbane/10/07株,对BALB/C小鼠、Scid小鼠、NOD/LTJ小鼠、BALB/C-nu小鼠、NOD-Scid小鼠和icosl-KO小鼠经乙醚麻醉后进行滴鼻攻毒。检测小鼠感染后肺组织病毒拷贝数并观察肺组织病理学改变。结果 H1N1和H3N2滴鼻攻毒的各组小鼠均染毒,病理表现为程度略有差异的间质性肺炎。13只H1N1病毒感染小鼠和6只H3N2感染小鼠在肺组织中观察到多个小血管内有血栓形成,血栓成分主要为纤维素和血小板。结论各品系小鼠感染H1N1和H3N2流感病毒后均可能出现肺组织内血栓形成。     

Inhibition of H. pylori colonization and prevention of gastritis in murine model

Helicobacter pylori is a Gram-negative spiral bacterium that colonizes human gastric mucosa causing infection. In this study aiming at inhibition of H. pylori infection we made an attempt to evaluate immunogenicity of the total (UreC) and C-terminal (UreCc) fragments of H. pylori urease. Total UreC and its C-terminal fragment were expressed in E. coli. Recombinant proteins were analyzed by SDS-PAGE and western blot and then purified by Ni-NTA affinity chromatography. Female C57BL6/j mice were immunized with the purified proteins (UreC and UreCc). Antibody titers from isolated sera were measured by ELISA. Immunized mice were then challenged by oral gavage with live H. pylori Sydney strain SS1. Total of 109 CFU were inoculated into stomach of immunized and unimmunized healthy mice three times each at one day interval. Eight weeks after the last inoculation, the blood sample was collected and the serum antibody titer was estimated by ELISA. Stomach tissues from control and experimental animal groups were studied histopathologically. UreC and UreCc yielded recombinant proteins of 61 and 31 kDa respectively. ELIZA confirmed establishment of immunity and the antibodies produced thereby efficiently recognized H. pylori and inhibited its colonization in vivo. Pathological analysis did not reveal established infection in immunized mice challenged with H. pylori. The results support the idea that UreC and UreCc specific antibodies contribute to protection against H. pylori infections.     

无标签鼠疫耶尔森菌Ⅴ抗原突变体在大肠杆菌中的表达、纯化及免疫原性分析

目的:在大肠杆菌中表达、纯化无标签鼠疫耶尔森菌低钙反应V抗原突变体,并对其免疫原性进行研究。方法:采用融合PCR方法将Ⅴ抗原基因中编码半胱氨酸的碱基缺失突变,将获得得Ⅴ抗原突变体基因克隆到原核表达载体pET32a(+)后转化大肠杆菌BL21(DE3),用IPTG诱导表达并进行柱层析纯化,纯化产物以Western印迹进行鉴定并免疫BALB/c小鼠,通过ELISA检测免疫血清效价。结果:目的蛋白在大肠杆菌中获得了可溶性高表达,经三步柱层析后纯度高于95%,经Western印迹检测可与野生型V抗原单克隆抗体特异性结合,免疫小鼠后获得高效价免疫血清。结论:获得了无标签的鼠疫耶尔森菌Ⅴ抗原突变体蛋白,并证实其具有免疫原性,将对V抗原结构和功能的研究提供帮助。     

H7N9禽流感病毒小鼠感染动物模型的建立

目的建立H7N9禽流感病毒小鼠感染模型。方法 1×108,1×107或1×106TCID50H7N9禽流感病毒原液(A/Anhui/1/2013)滴鼻感染BALB/c小鼠。主要观测指标:临床症状、死亡率、病理变化、病毒载量和血清抗体检测。结果被感染的小鼠表现为竖毛、弓背、体重下降;病理表现为间质性肺炎,感染后第2天开始在呼吸道脱落细胞中检测到病毒;免疫组化或病毒分离方法在肺、肾、脑、肠、脾等组织检测到病毒;感染后14 d在小鼠血清中血凝抑制试验特异性抗体效价达到160;淋巴细胞减少,中性粒细胞增多。结论 H7N9感染BALB/c小鼠模型与人类禽流感感染疾病的基本特征相似,为研究该病的发病机制及药物疫苗的研发提供了工作基础。