口服幽门螺杆菌苗免疫小鼠后胃粘膜的免疫应答

目的 观测Hp全菌抗原和粘膜佐剂LT口服免疫Balb/c小鼠后的胃肠粘膜免疫反应。方法 采用ELISPOT法检测了胃粘膜、肠粘膜相关淋巴组织PP结抗原特异性形成细胞（AFC）。结果 抗原免疫组、抗原 佐剂组胃肠粘膜抗原特异性sIgA-AFC、IgG-AFC数量明显增加,尤以sIgA-AFC为甚。并且抗原 佐剂组明显高于单纯抗原组和对照组。结论 口服菌苗可有效诱导胃肠道粘膜免疫应答。局部sIgA可能在抗Hp感染中具有重要作用。     

幽门螺杆菌全菌抗原口服免疫BLAB／c小鼠的免疫应答机理研究

目的 分析幽门螺杆菌全菌抗原的口服免疫应答反应。方法 ELISA分析免疫小鼠血清、唾液、粪便提取物特异抗体水平,ELISPOT分析胃粘膜、派伊尔小结（PP）抗原行异性抗体分泌细胞（ASC）,RT－PCR分析PP T细胞因子mRNA表达水平。结果 ①口服免疫可诱导强烈的血清IgG反应和唾液、粪便提取物特sIgA反应;②胃粘膜、PP结产生大量抗原特异性抗体分泌细胞（ASC）,尤以sIgA-ASC型居多,PP结抗原特异性形成细胞（ASC）数量与特异抗体水平密切相关;③加佐剂免疫组小鼠PP T细胞,体外抗原刺激下,早期高表达IFN－γ晚期高表达IL－4。结论 全菌抗原和粘膜佐剂免疫可诱导H.pylori特异的系统、粘膜免疫应答,局部sIgA可能在抗H.pylori感染中具有重要作用,肠粘膜免疫主要诱导部位PP早期表现为TH1型优势应答,晚期则转为TH2型优势应答。     

人幽门螺杆菌尿素酶抗体诊断试剂盒的研制

幽门螺杆菌 (Ｈｅｌｉｃｏｂａｃｔｅｒｐｙｌｏｒｉ,Ｈ .ｐｙｌｏｒｉ)为慢性胃炎、消化性胃溃疡的致病菌 ,并且与胃癌的发生密切相关 ,世界卫生组织 (ＷＨＯ)将其列为一级致癌因子 ,早期诊断Ｈ .ｐｙｌｏｒｉ感染并对其治疗和预后的观察具有重要意义。目前 ,临床上用于诊断Ｈ .ｐｙｌｏｒｉ感染的方法主要有胃镜下组织活检、细菌培养、13 Ｃ呼气试验等 ,前者需活检组织 ,病人痛苦大 ,且阳性率低 ,后者需特殊性设备 ,不易推广 ,细菌培养则阳性检出率低 ,而血清学诊断具有灵敏、快速、准确、简便、费用低等优点 ,易在临床上广泛使用。但是 ,…     

产空泡毒素幽门螺杆菌感染的临床意义

幽门螺杆菌 (Ｈｅｌｉｃｏｂａｃｔｅｒｐｙｌｏｒｉ,Ｈｐ)感染是慢性活动性胃炎、消化性溃疡和萎缩性胃炎的重要病因之一 ,并与胃癌、胃淋巴瘤的发生密切相关 ,其中人群中的感染率超过 50 % ,目前已被世界卫生组织列为一级致癌因子〔1〕。Ｈｐ的致癌因子包括 :尿素酶、脂多糖、热休克蛋白、磷脂酶和空泡毒素 (ｖａｃｕｏ ｌａｔｉｎｇｃｙｔｏｔｏｘｉｎ ,ＶａｃＡ)等。其中ＶａｃＡ蛋白仅有部分菌株产生 ,可引起上皮细胞出现空泡样变及胃粘膜病变。为了解重庆地区ＨｐＶａｃＡ 株的感染与不同消化道疾病的关系 ,我们采用ＥＬＩＳＡ法和细…     

PELA幽门螺杆菌口服疫苗微球黏膜免疫研究

目的：应用复乳挥发法制备PELA泛影葡胺显影微球与缨门螺杆菌超声上清口服疫苗微球，并进行靶向与黏膜免疫研究。方法：采用CT技术，研究显影微球的靶向，PELA幽门曙杆菌超声上清口服疫苗微球口服免疫小鼠后，运用ELISA法检测血清，唾液，肠粘液的抗体改变情况，ELISPOT法分析派伊尔氏结（PP结）抗原特异性抗体形成细胞（ASC）的数量增减，结果；口粒径在10um以下的微球，首先粘附在胃肠黏膜表面，后投递于PP结；H.pylori疫苗微球免疫后可诱导较高的唾液sIgA水平和肠道sIgA反应，PP结抗原特异性抗体形成细胞（ASC）数量与肠道 sIgA水平密切相关，结论：可生物降解的PELA微球可用于靶向口服疫苗的研究。     

幽门螺杆菌微球疫苗免疫诱导的免疫应答

目的通过对幽门螺杆菌微球免疫后Balbc小鼠血清IgG、IgA、胃肠sIgA的检测及脾脏IL4、IFNγ的mRNA表达水平、IgGASC、IgAASC数量的比较观察,探求疫苗的免疫保护机理。方法取Balbc小鼠口服免疫疫苗,剂量为150μg/(只·次),免疫时间为0、14、30d。2周后取血清及胃肠洗液进行抗体检测,同时取脾脏检测细胞因子mRNA表达水平及ELISPOT检测抗体分泌细胞数量变化。结果免疫后小鼠以上检测指标与对照组比较均有不同程度的升高。结论微球疫苗所诱发的免疫保护是细胞免疫、体液免疫两者共同作用的结果。     

幽门螺杆菌粘附素基因babA2的克隆及免疫应答的初步研究

目前，幽门螺杆菌(Helicobacter pylori，Hp)疫苗的研制仍处在抗原的筛选阶段，已经评价的基因重组抗原基本上是着眼于阻断Hp的毒力因素，而与Hp定植密切相关的粘附素评价较少。babA是迄今为止唯一明确受体的Hp粘附素，研究表明babA基因存在两个等位基因：babA1和babA2，其中只有babA2：具备与Le^b结合的功能。本实验对babA2基因进行了克隆和表达并研究了其免疫反应。     

幽门螺杆菌相关抗原及宿主免疫应答的研究进展

幽门螺杆菌与多种胃肠道疾病诸如慢性胃炎,胃肠溃疡,胃腺瘤及胃癌等密切相关的结论已得到证实,预防和治疗幽门螺杆菌感染是控制其广泛传播的有效途径,此项工作虽早已开始,但至今未找到可行的方案.近来对幽门螺杆菌相关毒素的研究越来越多,这可作为研究幽门螺杆菌菌苗的重要依据;幽门螺杆菌诱发的宿主免疫应答以TH1反应为主,幽门螺杆菌感染者可出现系统和局部的抗体反应,这些抗体反应对机体不具保护作用且自身抗体对宿主上皮细胞还可能带来不良影响,阐明宿主免疫应答的机制对预防和治疗幽门螺杆菌感染具特殊意义.因此,本文主要介绍了脲素酶、空泡细胞毒素、cag相关基因蛋白,中性粒细胞蛋白等几种毒素及宿主免疫应答的研究现状,并对幽门螺杆菌的研究前景进行综述.     

抗重组幽门螺杆菌VacA单克隆抗体的制备

目的 制备抗重组幽门螺杆菌致细胞空泡毒素抗原(VacA)的单克隆抗体(mAb).方法 用基因工程菌pQr30-v-DH5α大最表达重组蛋白VaeA,经Ni2+-NTA树脂纯化后,Western blot鉴定抗原性,免疫家兔后ELISA法检测血清VacA抗体鉴定其免疫原性.用重组vacA免疫Balb/c小鼠.取免疫鼠脾细胞与骨髓瘤SP2/O细胞融合,HAT选择性培养和间接EIJSA进行筛选,并检测所分泌抗体的效价和分析Ig类别.结果 获得4株能稳定分泌VacA mAb的杂交瘤细胞,能分泌IgG2b、lgM和IgG1 3类抗体,轻链均为k型.其中,IgG1 mAb经Western blot鉴定能与重组VacA发牛特异性反应.结论 应用纯化的重组VacA,成功获得了能稳定分泌幽门螺杆菌VacA单克隆抗体的杂交瘤细胞,并制备了单克隆抗体.为进一步研制检测VacA的试剂盒及探讨VacA的致病机制奠定了基础.     

幽门螺杆菌感染小鼠及其抗原免疫小鼠后体液免疫应答的比较

目的：比较BALB／c小鼠感染H.pylori后以及经H.pylori UreB抗原口服免疫后的体液免疫应答的差异。方法：80只BALB／c小鼠分为感染组和免疫组，感染组灌喂H.pylori小鼠适应株；免疫组灌喂重组H.pylori UreB抗原和佐剂LTB。在试验的0，2，6和10周时每组分别取10只小鼠收集唾液及血液标本，用ELISA法检测抗UreBIgG和IgA抗体，同时采集胃组织作H.pylori感染检测。结果：感染组小鼠在灌喂H.pylori后2，6，10周，感染率均为100％，其血清中抗UreB IgG增高明显，但血清及唾液中均未见IgA的明显升高，；免疫组小鼠在初次免疫后第6，10周后，血清及唾液中抗UreB,IgG和IgA抗体的均显著升高。结论：H.yplori感染BALB／ c小鼠不能诱导其产生明显的特异性黏膜免疫应答，而重组UreB可作为良好的免疫原诱导其产生分泌型IgA抗体。     

Effect of antioxidants on the immune response of Helicobacter pylori

Antioxidants are substances capable of inhibiting oxidation. In chronic diseases, inflammatory response cells produce oxygen free radicals. Oxygen free radicals cause DNA damage, and this may lead to gene modifications that might be carcinogenic. Chronic Helicobacter pylori infection causes the production of DNA-damaging free radicals. In recent years, various groups have studied the effects of antioxidants, especially on H. pylori -associated gastric cancer. In most of the studies, it has been shown that H. pylori infection does affect the level of antioxidants measured in the gastric juice, but there are also controversial results. Recent experimental studies, both in vivo and in vitro, have shown that vitamin C and astaxanthin, a carotenoid, are not only free radical scavengers but also show antimicrobial activity against H. pylori. It has been shown that astaxanthin changes the immune response to H. pylori by shifting the Th1 response towards a Th2 T-cell response. Very few experimental studies support the epidemiologic studies, and further studies are needed to describe the effect and the mechanism of antioxidants in the H. pylori immune response.     

幽门螺杆菌疫苗免疫机制的研究进展

幽门螺杆菌(H.pylori)是定植于人体胃粘膜的重要致病菌,而粘膜疫苗以其有效的保护性免疫成为防治H.pyiori的热点,但对相应的免疫机制的认识目前尚不明确.故本文对H.pyiori疫苗的保护性免疫机制中的抗原递呈机制,抗体的作用以及TH细胞反应的作用等研究进展做一概要介绍.     

Helicobacter pylori and the innate immune system

Since its discovery, Helicobacter pylori surprises us by its ability for life-long chronic persistence, proliferation, and probably active adaptation in the unfavourable niche of the human stomach, without being eliminated by the defence systems of the human body. This minireview highlights recent developments about the interaction of H. pylori with the innate immune system, and makes a case that evasion and possibly suppression of innate immune responses play an important role for the active survival in its local mucosal environment.     

IgA antibodies in persisting Helicobacter pylori infection in Finnish adults

Most individuals infected with Helicobacter pylori have elevated levels of specific IgG antibodies, but only in about two-thirds of cases does the IgA titre exceed the cut-off level. The aim of this study was to determine whether H. pylori-infected subjects with elevated IgG levels would subsequently produce IgA antibodies, and whether elevated IgA levels increased during infection. Paired sera were available from 336 adults who took part in a large population-based health survey in 1977-1980 and a follow-up study on asthma and atopic diseases in 1997-1998 (series A). Data on paired sera from 224 adults who participated in a population-based health survey in Vammala, Finland in 1973 and who gave a follow-up blood sample in 1994 (series B) were also re-analysed. H. pylori IgG and IgA levels were determined with commercially available (series A) and in-house (series B) enzyme immunoassays. Twenty-one (35%) of the 60 subjects who initially had elevated levels of IgG antibodies only were found to be IgA-positive at follow-up. In those subjects whose baseline and follow-up samples were IgG- and IgA-positive, the median IgA levels increased by 48% and 22% in series A and B (p < 0.0001 and p 0.0241), respectively, whereas the median IgG levels did not change significantly in either series. During H. pylori infection, an increase in specific IgA was reflected by the increase in the number of responders and by the rise in titres.     

Advantage of using a home-made ELISA kit for detection of Helicobacter pylori infection over commercially imported kits

PURPOSE: To evaluate a home-made ELISA kit for detection of Helicobacter pylori (Hp) infection and comparison of its immunologic criteria with those of foreign commercial kits. METHODS: A home-made IgG ELISA kit was developed using soluble antigenic fractions of Hp proteins. Confirmed sera were tested and serological criteria were evaluated through assessment of 199 serum samples. RESULTS: The accuracy, sensitivity and specificity values of home-made kit were 92, 92 and 90.4%, respectively. These immunologic criteria for Trinity kit were 95.2, 95.2 and 95% in comparison with IBL kit (91.3, 92.2 and 88.5%), BIOHIT kit (72.4, 41.6 and 94.1%) and HelicoBlot2.1 (94.2, 93.4 and 100%). Kappa agreement assessment demonstrated that two of the imported ELISA kits had fair to moderate agreement with the home-made kit while the other one had a poor agreement value. CONCLUSIONS: Apart from comparable values between the home-made kit and the most efficient imported kit (Trinity) there was significant cost benefit. Therefore, we recommend the home-made kit as a suitable substitution for detection of Hp infection in the Iranian population.     

IgG subclass response to Helicobacter pylori and CagA antigens in children

Specific serum IgG subclass antibodies against Helicobacter pylori antigens and recombinant CagA were analysed in 75 symptomatic children with histologically confirmed H. pylori infection. H. pylori stimulated an IgG1 predominant response, and IgG3 titres showed a positive association with peptic ulcer disease, chronicity of antral inflammation and density of H. pylori colonization. Two methods used for assessing serum IgG CagA antibody status, i.e. Western blotting and enzyme-linked immunosorbent assay (ELISA), were concordant. CagA stimulated an IgG1 and IgG3 predominant humoral response. Total CagA IgG titres were higher in children with active and more severe chronic antral inflammation. These findings suggest that in children the systemic humoral immune response to H. pylori infection may reflect gastroduodenal pathology.     

Helicobacter pylori infection in patients with selective immunoglobulin a deficiency

Selective immunoglobulin A (IgA) deficiency (IgAD) is the most common primary immunodeficiency in the western world. The aim of the study was to investigate the prevalence and clinical characteristics of Helicobacter pylori‐infected dyspeptic patients with IgAD. Case samples were drawn from all subjects ≥ 12 years of age (n = 104729) who had undergone serum total IgA measurements during 2004–14 for any reason at Leumit Healthcare Services (Israel) and had serum total IgA < 0·07 g/l. The control group was comprised of a random sample of remaining patients with a case–control ratio of 10 controls for each case. The dyspeptic diseases were identified and retrieved from Leumit Health Care Services electronic database using specific ICD‐9‐CM diagnostic codes. The case group included 347 subjects and the control group 3470 subjects. There were no significant differences in the prevalence of patients with dyspepsia [84 (24·2%) versus 821 (23·6%) for cases and controls, respectively]. Additionally, there was no difference in a proportion of dyspeptic H. pylori‐positive subjects [59 (17·1%) versus 524 (15·1%)] between the case and control groups. Only 59 (17%) among the 347 IgAD patients underwent gastroscopy. A significantly larger proportion of case subjects experienced several forms of gastritis [13 (61·9%) versus 38 (21·6%), P < 0·001), duodenal ulcers [seven (33·3%) versus 19 (10·8%); P = 0·01] and nodular lymphoid hyperplasia (NLH) [two (9·5%) versus none; P = 0·011]. IgAD is not associated with increased prevalence of H. pylori‐associated dyspepsia; nevertheless, H. pylori‐infected dyspeptic IgAD subjects experience more EGD‐proved gastritis, duodenal ulcers and NLH.     

Single nucleotide polymorphism of interleukin-1β associated with Helicobacter pylori infection in immune thrombocytopenic purpura

To examine the role of genetic factors in development of immune thrombocytopenic purpura (ITP) in association with Helicobacter pylori infection, gene polymorphisms within the loci for human leukocyte antigen class II, interleukin (IL)-1β (−511), tumor necrosis factor-β (+252), immunoglobulin (Ig)G1 heavy chain (+643), and Igκ light chain (+573) were determined in 164 adults with ITP and 75 healthy controls. Of these gene polymorphisms, the IL-1β (−511) T allele was less frequently detected in H.   pylori -infected than in H.   pylori -uninfected (58% vs 81%, P  = 0.01, odds ratio = 0.31) ITP patients diagnosed before age 50. These findings suggest that a single nucleotide polymorphism within the IL-1β (−511) may affect susceptibility to early-onset ITP associated with H.   pylori infection.