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1.
RT-PCR扩增45W-4B和TSOL18基因,PCR截去45W-4B基因的N端信号肽和C端疏水氨基酸序列形成45W-4BX。将45W-4BX和TSOL18 PCR产物分别亚克隆人pGEX-4T-1,用IPTG诱导表达,取产物进行SDS-PAGE和Western blot分析。纯化表达产物制成油佐剂疫苗分别免疫家猪,用25000枚猪带绦虫成熟虫卵进行攻击感染,ELISA检测各组的抗体水平,90d后剖检计算各组的减虫率。结果表明,45W-4BX和TSOL18基因在大肠杆菌中分别以可溶性和包涵体形式获得高效表达,并能被囊虫病人血清所识别。重组蛋白免疫猪15d血清抗体即为阳性,30d左右达到峰值。2种重组抗原的减虫率均在88%以上,与囊虫粗抗原免疫效果相当。这为进一步研制基于45W-4BX和TSOL18的猪囊虫重组基因工程疫苗奠定了基础。  相似文献   

2.
猪囊虫病基因工程疫苗的研制   总被引:11,自引:0,他引:11  
从猪带绦虫六钩蚴cDNA文库中筛选目的基因并进行克隆表达,重组抗原用血清学方法和猪体免疫进行鉴定。钭具有免疫保护作用的重组抗原纯化,与免疫刺激复合物疫苗佐剂混合,制备成猪囊虫病基因工程疫苗,免疫仔猪并攻虫。该疫苗安全,无毒副作用,免疫猪减虫率92.2%,完全保护率55.5%,且免疫组发现的囊虫多数已死亡。  相似文献   

3.
为获得针对猪带绦虫六钩蚴(TSO)45W-4BX抗原的杂交瘤细胞株,用IPTG对TS045W-4BX的重组质粒pGEX-4BX进行了诱导表达,并采用Sepharose-4B层析技术对表达产物进行纯化,运用SDS—PAGE和Western—blot分别对其纯度和活性进行了检测。分别用弗氏完全佐剂、弗氏不完全佐剂乳化已纯化的猪带绦虫TS045W-4BX重组抗原,随后用其分别免疫BALB/c小鼠3次,检测血清抗体效价呈阳性。之后,再进行加强免疫,取免疫小鼠脾细胞和SP2/0细胞进行融合,经TS045W-4BX抗原和GST抗原双系统间接ELISA筛选,最终获得了18株抗TS045W-4BX抗原的杂交瘤细胞株。采用有限稀释法对其中的4株进行5次亚克隆,最终获取了4株稳定分泌针对TS045W-4BX抗原的单克隆抗体的杂交瘤细胞株,金标试纸条法鉴定其抗体亚类均属于IgG1类,轻链为κ型。  相似文献   

4.
猪病毒性腹泻三联疫苗的免疫研究   总被引:5,自引:1,他引:5  
用猪传染性胃肠炎病毒、猪流行性腹泻病毒、猪轮状病毒制备的三联疫苗对8头怀孕母猪进行免疫,所产73头仔猪保护率89%;对110头仔猪进行口服免疫,21天用三种强毒混合毒攻击,免疫组保护92.7%,对照组发病84.8%,经测定疫苗免疫期为4个月,干燥阴凉条件下保存期为12个月。田间受免仔猪2744头,免疫保护90%。  相似文献   

5.
猪旋毛虫病疫苗后海穴免疫研究   总被引:1,自引:0,他引:1  
本项目对猪旋毛虫病成虫可溶性抗原疫苗经后海穴免疫注射的效果进行了研究。大鼠经口感染旋毛虫肌幼虫后3或7d剖杀,收集成虫。经超声粉碎、高速离心制备成虫可溶性抗原。将抗原与等体积FCA乳化,按0.25mg/头及0.50mg/头的抗原量分别进行后海穴注射(AP)及腹腔注射(IP),免疫猪只,使之经受旋毛虫的实验室攻击感染及自然感染。结果表明,3日龄及7日龄成虫可溶性抗原的免疫原性基本一致。采用后海穴注射疫苗具有减少抗原用量、增强免疫效果的作用。免疫后猪血清抗体滴度增加,呈暂时的细胞免疫抑制现象。后海穴注射疫苗猪群保护率达100%,增加一倍抗原量经腹腔注射的猪群保护率为75.26%。  相似文献   

6.
试验用同一批次相同抗原含量的口蹄疫病毒灭活抗原,分别采用纳米乳佐剂和ISA206佐剂配制口蹄疫O型、A型双价灭活疫苗,并对仔猪进行免疫,免疫后6个月内用液相阻断ELISA方法检测O型、A型免疫抗体效价(lg)。结果:免疫后6个月内纳米乳疫苗免疫猪产生的抗体lg平均值均高于ISA206佐剂疫苗,抗体水平在免疫后1个月达到最高。免疫后第6个月,纳米乳疫苗O型抗体lg平均值为2.19,A型抗体lg平均值为2.175,按液相阻断ELISA试剂盒的判定标准免疫猪抗体lg≥1.8,具有99%以上保护效力,纳米乳疫苗属于完全保护范围,而ISA206佐剂疫苗属于不完全保护范围。  相似文献   

7.
猪囊虫病基因工程疫苗的研制及应用   总被引:6,自引:1,他引:6  
从猪带绦虫六钩蚴cDNA文库中筛选目的基因并进行克隆表达,重组抗原用血清学方法和猪体免疫试验进行鉴定,筛选保护性抗原基因。将具有免疫保护作用的重组抗原纯化,并与免疫刺激复合物佐剂结合,制成猪囊虫病基因工程疫苗。对工程菌的培养发酵、重组抗原的下游纯化及疫苗的配制、疫苗的中间试制进行了研究,确定了一套比较完善的生产工艺。应用昆明小鼠建立了猪囊虫病的实验动物模型,应用该模型进行上述疫苗的免疫预防试验,免疫1次和2次的免疫保护率分别为96.9%和98.4%。本动物的免疫预防试验显示,疫苗安全性好,免疫保护率达92.2%,且免疫组发现的囊虫多数已死亡。在流行区进行了田间和区域试验。免疫猪未有不良反应,囊虫感染率分别由20%降为1.1%和5.4%降为0.21%。用该疫苗对人工感染的囊虫病猪进行免疫治疗,发现在感染早期的治疗效果较好。免疫动物的体液免疫和细胞免疫的检测结果显示,该疫苗刺激机体产生抗体的时间早、持续时间长、效价高;可显著提高淋巴细胞转化率及E-RFC和Ea-RFC细胞、ANAE^ 细胞和粗粒型ANAE^ 细胞、抑制/杀伤性T细胞亚群的数量。以上结果表明,用大肠杆菌表达的重组抗原制备的猪囊虫病基因工程疫苗安全、高效,且成本低廉,可规模化生产,有成为预防猪囊虫病的一种新型生物制剂。  相似文献   

8.
异源性抗原抗猪囊尾蚴感染的研究   总被引:1,自引:0,他引:1  
本文报道了泡状带绦虫活化六钩蚴的超声裂解抗原可以诱导猪体产生抗猪带绦虫攻击感染的交叉保护作用。猪囊尾蚴匀浆抗原也使猪体产生了较强的抗猪带绦虫攻击感染的保护作用。泡状带绦虫六钩蚴超裂抗原免疫组与猪囊尾蚴匀浆抗原免疫组的保护情况是相似的,这表明异源免疫也可使猪体产生较好的抗猪囊尾蚴感染的免疫。由于制备异源性抗原的泡状带绦虫能够从狗的体内获得,因此在体外培养猪带绦虫未获成功之前可以解决从人体获取猪带绦虫的困难。  相似文献   

9.
用猪瘟、猪肺疫、猪丹毒三联疫苗和猪丹毒1a、2型氢氧化铝吸附甲醛灭活疫苗分别免疫断奶仔猪,采用Dot-PPA-ELISA监测免疫猪血清抗体变化。结果,弱毒疫苗免疫后第7d猪丹毒血清抗体效价开始升高,第2~3周达最高值;灭活疫苗免疫后第3~4周抗体效价达最高值,且灭活疫苗免疫猪的抗体水平明显高于三联疫苗免疫猪。免疫6周后,用C43004(1a型)、C43179(1b型)和C43-12(2型)3株不同血清型的猪丹毒混合强毒同时对不同抗体效价的免疫猪和对照猪进行了皮肤内接种攻毒,并根据其皮肤和体温反应确定1:32为猪能抵抗混合强毒攻击的抗体保护效价。经对44头50~60日龄未免疫的断奶仔猪血清检测,其抗体效价在1:32以下的猪占88.36%,278头免疫猪血清的抗体效价在1:32或以上的猪占92.81%。表明Dot-PPA-ELISA适用于猪群猪丹毒的免疫监测和免疫力测定。  相似文献   

10.
对试验猪用猪囊尾蚴细胞抗原免疫前、感染前、免疫后及用猪带绦虫卵感染后每隔10d经前腔静脉采血1次,分离血清,同时制备全血干血纸,分别用血清ELISA和干血纸ELISA进行检测。结果免疫组猪均在免疫后12d检出抗体;攻击感染组猪在攻击虫卵20d检出抗体,21d抗体水平达高峰,并一直持续到32周;阴性对照组的OD值一直在0.24~0.65。2种样品的检测结果基本一致。  相似文献   

11.
Cathepsin L-like proteases are secreted by several parasites including Taenia solium. The mechanism used by T. solium oncospheres to degrade and penetrate the intestine and infect the host is incompletely understood. It is assumed that intestinal degradation is driven by the proteolytic activity of enzymes secreted by the oncosphere. Blocking the proteolytic activity by an antibody response would prevent the oncosphere penetration and further infection. Serine and cysteine proteases including chymotrypsin, trypsin, elastase, and cathepsin L, are secreted by T. solium and Taenia saginata oncospheres when cultured in vitro, being potential vaccine candidates. However, the purification of a sufficient quantity of proteases secreted by oncospheres to conduct a vaccine trial is costly and lengthy. A 53/25 kDa cathepsin L-like fraction partially purified from T. solium cyst fluid was described previously as an important antigen for immunodiagnostics. In this study we found that this antigen is present in the T. solium oncosphere and is also secreted by the cysticercus. This protein fraction was tested for its ability to protect pigs against an oral challenge with T. solium oncospheres in a vaccine trial. IgG antibodies against the 53/25 kDa cathepsin L-like protein fraction were elicited in the vaccinated animals but did not confer protection.  相似文献   

12.
Immunity to Taenia solium infection was investigated using an experimental intramuscular oncosphere infection assay (IMOA) model in pigs. Three naturally infected pigs with cysticercosis were treated with oxfendazole (OFZ), a drug demonstrated to kill cysts in porcine muscle. These animals were then challenged with oncospheres but did not develop any cysts while three uninfected pigs that were similarly challenged, did develop intramuscular cysts. In another study, two groups of three pigs each were immunized with crude T. solium oncosphere and metacestode antigens, respectively, and tested with the IMOA. Immunization with crude oncosphere antigens (OAs) induced 100% protection, while metacestode antigens provided only partial protection. Immunoblots showed that pigs with complete immune protection to oncosphere intramuscular challenge had antibodies to two OAs at 31.3 and 22.5 kDa, respectively. Antibody to these two antigens was absent in pigs immunized with metacestodes or in uninfected control pigs. This study demonstrated the presence of two antigens that are unique to the oncosphere. Although, antibody to these two antigens is consistently present in pigs that are protected from an oncosphere intramuscular challenge their role in preventing infection by T. solium larval cysts is still hypothetical.  相似文献   

13.
Vaccination of pigs of mixed genetic make-up, raised as rustically as done in rural Mexico, resulted in effective protection to experimental challenge against Taenia solium cysticercosis. Maximum protection was achieved if pigs were immunized at 70 days of age. There was large variation of viable parasite load within vaccinated pigs and controls, which is suggestive of significant genetic factors influencing susceptibility, besides immunization. Our results strengthen the advisability of pig vaccination for control of T. solium cysticercosis, since it lowers the number of viable cysticerci capable of transforming into tapeworms.  相似文献   

14.
Evaluation of serology using glycoproteins (GPs) purified by preparative isoelectric focusing (pH 8.8) and recombinant chimeric antigen (RecTs) of Taenia solium was carried out using (1) blood samples on filter papers from pigs infected with different doses of eggs of T. solium in Mexico, (2) serum samples from pigs found infected naturally in Vietnam and Ecuador and (3) serum samples from pigs suspected to be infected with T. solium by tongue inspection in Tanzania. Antibody responses (IgG) were detectable in experimentally infected pigs confirmed harbouring 16 or more cysts at necropsy from 30 days after egg inoculation. One of three pigs naturally infected and harbouring 2.5 cysts/kg muscle and most of pigs harbouring=5.0 cysts/kg were also seropositive by ELISA. Although pigs may be infected with other taeniid species such as Taenia hydatigena, pigs harbouring this parasite were negative in ELISA. Approximately, 76 and 78% of sera from pigs having nodule(s) in the tongue (positive tongue inspection) were serologically positive by both ELISA and immunoblot, respectively. Furthermore, approximately 34 and 18% of sera from pigs having no nodules in the tongue (negative tongue inspection) were also seropositive by ELISA and immunoblot, respectively. ELISA using the two antigens was more sensitive than immunoblot and reliable for differentiation of pigs infected with cysticerci of T. solium from those either uninfected or infected with other taeniid species. Pigs without nodule by tongue inspection should be checked serologically in endemic areas.  相似文献   

15.
猪带绦虫45W基因已被认为是预防猪囊虫病的基因工程疫苗候选基因之一。其中4B基因是45W基因家族中高度保守的一个成员(以下称45W-4B)。本试验将重组于pGEM-3Z载体上的4B基因转载到pVL1393转移载体中,通过鉴定获得重组质粒pVL1393-4B,然后将重组质粒与BmNPV病毒共转染,筛选出重组BmNPV-4B重组病毒,用该重组病毒感染Bm细胞,收集细胞上清,SDS-PAGE电泳鉴定表达蛋白,并经Western blot检测表明该蛋白能识别囊虫病人(猪)阳性血清,45W-4B蛋白的成功表达对进一步研究45W蛋白的结构和功能以及开发高效猪囊虫基因工程疫苗打下了基础。  相似文献   

16.
Highly effective recombinant vaccines have been developed against the helminth parasites Taenia ovis, Taenia saginata and Echinococcus granulosus. These vaccines indicate that it is possible to achieve a reliable, high level of protection against a complex metazoan parasite using defined recombinant antigens. However, the effectiveness of the vaccines against the taeniid cestodes stands in contrast to the more limited successes which characterise attempts to develop vaccines against other platyhelminth or nematode parasites. This review examines the features of the host-parasite relationships among the taeniid cestodes which have formed the basis for vaccine development. Particular consideration is given to the methodologies that have been used in making the cestode vaccines that might be of interest to researchers working on vaccination against other helminths. In developing the cestode vaccines, antigens from the parasites' infective larval stage contained within the egg (oncosphere) were identified as having the potential to induce high levels of protection in vaccinated hosts. A series of vaccination trials with antigen fractions, and associated immunological analyses, identified individual protective antigens or fractions. These were cloned from cDNA and the recombinant proteins expressed in Escherichia coli. This strategy was independently successful in developing vaccines against T. ovis and E. granulosus. Identification of protective antigens for these species enabled rapid identification, cloning and expression of their homologues in related species and thereby the development of effective vaccines against T. saginata, E. multilocularis and, more recently, T. solium. The T. saginata vaccine provides an excellent example of the use of two antigen components, each of which were not protective when used individually, but when combined they induce a reliable, high level of protection. One important contributing factor to the success of vaccine development for the taeniid cestodes was the concentration on studies seeking to identify native host-protective antigens, before the adoption of recombinant methodologies. The cestode vaccines are being developed towards practical (commercial) application. The high level of efficacy of the vaccines against T. solium cysticercosis and hydatid disease suggests that they would be effective also if used directly in humans.  相似文献   

17.
Groups of dogs reared free of both nematodes and cestodes were infected with Taenia hydatigena, Taenia pisiformis or Echinococcus granulosus. After infections with the Taenia spp became patent, dogs were purged to remove the worms. They were later reinfected and the second infections again removed by purging after patency. A group of 3 uninfected worm free dogs was kept as age-matched controls. The dogs were bled at intervals of 5 days and their serums tested for antibodies using the enzyme-linked immunosorbent assay (ELISA) with excretory/secretory (ES) antigens collected during in vitro incubation of evaginated scoleces (scolex ES antigen) and oncosphere antigens. Antibodies to scolex ES antigen were detected by 3 weeks after infection with each cestode species whereas antibodies to oncosphere antigen were not detected until about one week after eggs were found in the faeces of the infected dogs. Antibody responses to both oncosphere and scolex ES antigens decreased rapidly following removal of the worms by purging. Uninfected control dogs were invariably negative to both oncospheral and scolex ES antigens. There were cross-reactions between the serums from dogs infected with T. pisiformis and T. hydatigena when tested with scolex ES antigens, but oncospheral antigens showed a high degree of species specificity. Scolex ES antigens from E. granulosus were compared with those prepared from T. hydatigena and T. pisiformis for their ability to discriminate between antibodies in serums collected from dogs 31 and 32 days after infection with 100,000 protoscoleces of E. granulosus or dogs infected with Taenia spp.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
A fraction with a major band of 14kDa was obtained from crude cyst fluid of Taenia solium cysticerci by 2-step chromatography. A first fraction isolated by gel filtration (Sephacryl S-300 high resolution) was purified using an anion exchange column (Mono Q HR 5/5) on high performance liquid chromatography. Evaluation of the analytic sensitivity of this fraction (F3) was carried out in an antibody enzyme linked immunosorbent assay (Ab-ELISA-F3) using serum samples from pigs experimentally infected with different doses of T. solium eggs. The cross-reactivity of F3 was evaluated with serum samples from pigs that were naturally or experimentally infected with Taenia hydatigena, Taenia saginata asiatica, Fasciola hepatica, Trichinella spiralis, Metastrongylus apri, Trypanosoma congolense and Sarcoptes scabiei, and with serum samples of rabbits hyper-immunised with metacestode cyst fluid of T. hydatigena and T. solium. Antibody titres of lightly or heavily infected pigs differed in their kinetics. However, the increase in F3-specific antibodies could not be related to the infection level. Analysis of the specificity of the F3 showed that serum samples of pigs infected with other parasites did not recognise this antigen. Cross-reaction with T. hydatigena occurred in ELISA using cyst fluid as antigen, but the F3 antigen fraction was not recognized by rabbit hyper-immune serum samples to T. hydatigena. Evaluation of the diagnostic sensitivity and specificity of the Ab-ELISA-F3 was done by a non-parametric receiver operating characteristic (ROC) analysis using 66 serum samples from Zambian village pigs. The total number of cysticerci of these pigs was determined by dissection (28 pigs harboured T. solium cysticerci and 38 were negative at dissection). In addition, 58 serum samples from Cameroonian pigs (28 pigs from cysticercosis-free farms and 30 pigs with cysticerci at tongue inspection) were used in a separate ROC analysis. The results from the ROC analysis yielded a low diagnostic value (area under ROC curve=0.48) with the sera from the Zambian pigs while a relatively high diagnostic value was obtained with the sera from Cameroonian pigs (area under ROC curve=0.78). The main factor contributing to a low diagnostic value based on the Zambian serum samples seemed to be the false-positive reactions that were likely caused by the occurrence of transient antibodies in the non-infected animals.  相似文献   

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