抗猪带绦虫六钩蚴独特型抗体疫苗对猪体免疫保护作用的研究

目的　本研究在证实猪带绦虫六钩蚴抗原具有很高的免疫保护性的基础上 ,探讨六钩蚴抗独特型抗体作为六钩蚴抗原替代物对猪体的保护作用 ,为研制猪体囊虫疫苗提供理论基础。　方法　用六钩蚴粗制抗原免疫家兔 ,制备兔抗六钩蚴抗体 (Ab1) ,再用Ab1免疫昆明小白鼠 ,制备抗独特型抗体 (Ab2 ) ,免疫猪体 ,以 3节猪带绦虫孕卵节片攻击感染 ,90d后剖杀 ,观察感染情况。　结果　 5头试验猪只有 1头在膈肌发现 1个囊虫 ,而 2头阳性对照猪均被感染 ,各检查部位囊虫数平均为 4.5个 /10 0g和 3 .2个 /10 0 g。　 结论　抗猪带绦虫六钩蚴独特性抗体Ab2对猪体有较强的免疫保护作用。     

抗猪带绦虫六钩蚴独特型抗体疫苗对猪体免疫保护作用的研究

目的本研究在证实猪带绦虫六钩蚴抗原具有很高的免疫保护性的基础上，探讨六钩蚴抗独特型抗体作为六钩蚴抗原替代物对猪体的保护作用，为研制猪体囊虫疫苗提供理论基础。方法用六钩蚴粗制抗原免疫家兔，制备兔抗六钩蚴抗体(Ab1)，再用Ab1免疫昆明小白鼠，制备抗独特型抗体(Ab2)，免疫猪体，以3节猪带绦虫孕卵节片攻击感染，90d后剖杀，观察感染情况。结果5头试验猪只有1头在膈肌发现1个囊虫，而2头阳性对照猪均被感染，各检查部位囊虫数平均为4．5个／100g和3．2个／100g。结论抗猪带绦虫六钩蚴独特性抗体Ab2对猪体有较强的免疫保护作用。     

抗囊虫病新型疫苗的研究进展

囊虫病 (Cysticercosis)是常见的人、畜寄生虫病 ,其中对人或家畜危害严重的有猪囊虫病、牛囊虫病和羊囊虫病 ,分别由猪带绦虫、牛带绦虫和绵羊带绦虫的中绦期所引起。该病的防治传统上以药物为主 ,但肉品中药物残留及对环境安全的危胁 ,使人们把目光重新投向安全、有效的疫苗研制和开发。传统疫苗所用抗原有全囊虫抗原、分泌 /代谢 (E/S)抗原、异源抗原以及六钩蚴抗原 ,这些疫苗都能对囊虫病起到很好的预防作用。但由于囊虫不能通过体外培养增殖 ,因而E/S抗原和全虫抗原来源都很有限 ,极大地限制了其应用 ,制约了囊虫病疫苗的研究。随着…     

抗囊虫病新型疫苗的研究进展

囊虫病(Cysticercosis)是常见的人、畜寄生虫病，其中对人或家畜危害严重的有猪囊虫病、牛囊虫病和羊囊虫病，分别由猪带绦虫、牛带绦虫和绵羊带绦虫的中绦期所引起。该病的防治传统上以药物为主，但肉品中药物残留及对环境安全的危胁，使人们把目光重新投向安全、有效的疫苗研制和开发。传统疫苗所用抗原有全囊虫抗原、分泌／代谢(E／S)抗原、异源抗原以及六钩蚴抗原，     

猪带绦虫六钩蚴TSO18基因研究进展

猪囊尾蚴病是一种严重危害人类健康的人兽共患寄生虫病,疫苗是预防控制猪囊尾蚴病的重要手段.TSO18基因是猪带绦虫六钩蚴阶段重要的免疫原基因,被认为是最具有前途的疫苗候选基因.该文综述了猪带绦虫六钩蚴TSO18基因的分子生物学及其疫苗开发的研究进展.     

猪囊尾蚴病免疫和诊断抗原的分子生物学研究进展

猪囊尾蚴病是一种危害严重的人兽共患寄生虫病。猪囊尾蚴特异性和保护性抗原的研究是猪带绦虫病、猪囊尾蚴病免疫和诊断的基础。天然抗原来源有限,限制了其应用,而重组抗原的应用可解决质量控制和抗原来源的问题。该文就近年来猪囊尾蚴病免疫和诊断抗原的分子生物学研究进展进行了综述。     

猪带绦虫六钩蚴超微结构的观察

目的 观察猪带绦虫六钩蚴的超微结构。 方法 猪带绦虫病患者驱虫,收集成熟虫卵。次氯酸钠法破卵壳后,等渗细胞分离液（Percoll）收集六钩蚴,人工肠液激活。热琼脂离心法制备电镜样品,透射电镜观察。 结果 猪带绦虫成熟六钩蚴呈卵圆形,（14～17）μm ×（10～13）μm,表面有不规则的突起或皱褶。六钩蚴小钩从外至内由颗粒带、纤维层和芯髓组成。成熟六钩蚴具成肌细胞、小钩生发细胞和皮层细胞等几种细胞类型。 结论 猪带绦虫六钩蚴的超微结构和缩小膜壳绦虫（Hymenolepis diminuta）六钩蚴的超微结构相似,但小钩的结构不同;猪带绦虫六钩蚴有形成上皮的双核细胞。     

猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位预测及鉴定

目的预测并鉴定猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位。方法利用生物信息学在线工具分析TSO45-4B抗原FnⅢ结构域序列并预测其线性B细胞表位;采用SWISS-MODEL软件预测TSO45-4B的蛋白空间结构,并合成两条预测表位肽。采用酶联免疫吸附试验(ELISA)检测猪囊尾蚴病人血清与两条预测表位肽的免疫反应性。结果获得2个TSO45-4B抗原FnⅢ结构域线性B细胞预测表位,其中1条预测表位合成肽可为猪囊尾蚴病患者血清识别。结论成功预测并鉴定了猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位。     

猪带绦虫六钩蚴抗原对猪体免疫保护作用的初步研究

本文报告猪带绦虫六钩蚴抗原对猪体的免疫保护作用，结果发现，免疫接种的实验动物没有感染，得到了完全保护，提示六钩蚴抗原对猪体有高度的保护作用；２头未免疫的对照组，１头雌猪感染较重，虫体负荷数为６６８，另１头雄猪没有感染，提示宿主的性别或不同的个体对猪带绦虫的易感性可能有差别。     

猪带绦虫六钩蚴抗原对猪体免疫保护作用的初步研究

本文报告猪带绦虫六钩蚴抗原对猪体的免疫保护作用，结果发现，免疫接种的实验动物没有感染，得到了完全保护，提示六钩蚴抗原对猪体有高度的保护作用；２头未免疫的对照组，１头雌猪感染较重，虫体负荷数为６６８，另１头雄猪没有感染，提示宿主的性别或不同的个体对猪带绦虫的易感性可能有判别。     

Vaccines for prevention of cysticercosis

Neurocysticercosis due to Taenia solium infection is an important cause of human morbidity and mortality. Despite the availability of effective anthelmintics, the disease remains prevalent in many parts of the world and there is a need for new and improved measures for control of the infection. An effective vaccine to prevent infection in pigs, the parasite's natural intermediate host, would be a valuable new option to assist with T. solium control. Several approaches are being used currently towards the development of a T. solium vaccine and these approaches are reviewed briefly, with emphasis on the use of recombinant oncosphere antigens. Highly effective vaccines have been developed against cysticercosis in sheep and cattle caused by Taenia ovis and Taenia saginata, respectively. This success has encouraged the adoption of a similar strategy for T. solium. The recent finding that one oncosphere antigen, TSOL18, can induce complete protection against T. solium infection in pigs, highlights the potential for development of a practical vaccine. A vision is proposed for the development of a safe, effective, inexpensive vaccine for pigs, which can be administered in an edible form. Through an international collaborative effort, research is progressing towards the realisation of such a vaccine and its use to reduce the global burden of neurocysticercosis.     

Vaccination of pigs to control human neurocysticercosis

Taenia solium taeniasis/cysticercosis is a zoonotic disease complex in which the pig is an obligate intermediate host. The infection is widespread, particularly in the developing world, and neurocysticercosis is a major cause of human neurologic disease where the parasite is endemic. Despite easy availability, effective anti-parasitic drugs have not been deployed effectively to control disease transmission. We have investigated a vaccine strategy to prevent parasite infection of the pig intermediate host. Such a strategy would interrupt the parasite's life cycle and eliminate the source of infection for humans. Two recombinant antigens selected from the parasite oncosphere life cycle stage were tested in vaccination trials in pigs that were challenged orally with Taenia solium eggs. Both antigens were highly effective in protecting the pigs against infection with the parasite (98.6% and 99.9% protection, respectively). No viable cysts were found in eight pigs vaccinated with one of the antigens. A recombinant subunit vaccine based on oncosphere antigens has the potential to improve the available control measures for T. solium and thereby reduce or eliminate neurocysticercosis.     

Antibody responses and epitope specificities to the Taenia solium cysticercosis vaccines TSOL18 and TSOL45-1A

Taenia solium is a cestode parasite that causes cysticercosis in humans and pigs. This study examined the antibody responses in pigs immunized with the TSOL18 and TSOL45-1A recombinant vaccines against T. solium cysticercosis. Immunization with these proteins induced specific, complement-fixing antibodies against the recombinant antigens that are believed to be associated with vaccine-induced protection against T. solium infection. Sera from immunized pigs were used to define the linear B-cell epitopes of TSOL18 and TSOL45-1A. Prominent reactivity was revealed to one linear epitope on TSOL18 and two linear epitopes on TSOL45-1A. These, and oncosphere antigens from other taeniid cestodes, contain a protein sequence motif suggesting that they may show a tertiary structure similar to the fibronectin type III domain (FnIII). Comparison of the location of linear antigenic epitopes in TSOL18 and TSOL45-1A within the proposed FnIII structure to those within related cestode vaccine antigens reveals conservation in the positioning of the epitopes between oncosphere antigens from different taeniid species.     

Cysticercosis vaccine: cross protecting immunity with T. solium antigens against experimental murine T. crassiceps cysticercosis

Vaccination of mice with an antigen extract from Taenia solium cysticerci induced protection against challenge with T. crassiceps cysticerci as successfully as did antigen extracts from T. crassiceps. Vaccination was more effective in male than in female mice and in the resistant strain (BALB/B) more so than in the susceptible strain (BALB/c). While only the resistant strain was completely protected by vaccination, the parasite load of the susceptible strain was significantly reduced by vaccination. Cross immunity between the human and murine parasites establishes murine T. crassiceps cysticercosis as a convenient laboratory model in which to test promising T. solium antigens aimed at vaccine development against T. solium cysticercosis. Further, results point to strong interactions of the immune system with sexual and histocompatibility factors in the host's dealing with cysticercosis.     

Taeniasis vs cysticercosis infection routes

Although cysticercosis caused by Taenia solium(T. solium) is considered a neglected disease, its life cycle has been well known for more than two centuries. T. solium not only causes cysticercosis but also taeniasis in humans. These two diseases have totally different infection routes. To acquire taeniasis(the presence of the adult stage of T. solium in the intestine), humans have to ingest the larval stage(cysticercus) that infects a variety of organs and viscera in pigs, its intermediate hosts. Therefore, taeniasis is acquired when eating raw or undercooked infected pork. The adult stage in the human intestine release eggs that contain a hexacanth embryo, the oncosphere. If humans accidentally ingest the eggs of T. solium, the released oncospheres penetrate the intestine and become cysticerci. Therefore, cysticercosis is acquired by the ingestion of eggs that contaminate water, vegetables, hands etc. These facts should not be forgotten to avoid misinformation in scientific publications.     

Human T and B cell epitope mapping of Taenia solium paramyosin

Taenia solium paramyosin is an immunodominant antigen in human and porcine cysticercosis that has shown promise as a vaccine candidate against schistosomiasis and some filariasis. There are few studies to identify the immunologically relevant regions of paramyosin. In this work, we characterize the humoral and cellular response of neurocysticercotic patients against T. solium paramyosin. Western blots using different recombinant fragments of T. solium paramyosin, showed that the sera from neurocysticercotic patients were strongly reactive against the carboxyl end region, with poor recognition of the central and amino regions. In contrast, the cellular immune response of patients did not show preferential recognition of any region of paramyosin.     

Human Taeniasis and cysticercosis in Asia

CONTEXT: Human Taeniasis caused by the pork, Taenia solium, or beef, T saginata, tapeworm arises after eating pork or beef contaminated with metacestodes, the larval stage of these parasites. Taeniasis with T solium can lead to neurocysticercosis and threaten others by accidental ingestion of eggs released from asymptomatic Taeniasis patients. The 2003 World Health Assembly declared that T solium is of worldwide public-health importance, and that it is an eradicable parasitic disease worldwide. Adult taeniid tapeworms expelled from people in almost all Asian countries appeared to be T saginata (the so-called Asian Taenia), even though they ate pork. The organism is now named T asiatica, and has been found in Taiwan, Korea, China, Vietnam, and Indonesia. But it has been difficult to differentiate T saginata from beef and Asian Taenia from pork. STARTING POINT: Marshall Lightowlers and colleagues (Int J Parasitol 2003; 33: 1207-17) recently demonstrated that recombinant oncosphere vaccines against several taeniid cestodes, including T ovis, T saginata, T solium, and Echinococcus granulosus, are highly effective. Protection was almost 100%, in the laboratory and in the field. These researchers found several common features, including a predicted secretory signal sequence, and one or two copies of a fibronectin type III domain, each encoded by separate exons within the associated gene. WHERE NEXT? Molecular and immunological techniques, including vaccine research and development of animal models for differentiation of taeniid species in humans, have greatly advanced over the past decade. The clinical importance of infections by these taeniids, including T asiatica, in humans, and the potential for cysticercosis attributable to T asiatica in humans, needs further study.     

Prevalence of antibodies to unique Taenia solium oncosphere antigens in taeniasis and human and porcine cysticercosis

The presence of two oncosphere antigens (OAs) of 22.5 and 31.3 kD in whole and excretory/secretory (ES) OA preparations of both Taenia solium and T. saginata or in antigen preparations from T. solium metacestodes or immature tapeworms was assessed. This included an evaluation of whether antibodies to other cestodes cross-reacted to these OAs. The OAs were present in whole oncosphere extract and E/S antigens of T. solium, but were not present in other stages (immature tapeworm or metacestode) or in OAs of T. saginata. The majority (95%) of T. solium tapeworm carriers had antibodies to these OAs, while only 20% of active neurocysticercosis cases were positive. No antibodies to the OAs were found in healthy controls, subjects infected with Hymenolepis nana, patients with hydatid disease, T. saginata tapeworm carriers, hamsters infected with immature T. solium tapeworms, or dogs infected with Echinococcus granulosus. The OAs are stage and species specific to T. solium and antibodies to OAs are usually present in tapeworm carriers.