Towards a vaccine against Fasciola hepatica using FhSAP2 as an antigen

使用 FhSAP2 作为抗原研制肝片形吸虫疫苗

• 批准号: 8016792
• 负责人: ANA M ESPINO
• 金额: $ 22.5万
• 依托单位: UNIVERSITY OF PUERTO RICO MED SCIENCES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2014-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8016792
• 关键词: Address; Adjuvant; Adverse effects; Affect; Agreement; Agriculture; Animals; Antibodies; Antigens; Bacterial DNA; Biological Assay; Cattle; Cells; Characteristics; Chronic; Chronic Phase; Dendritic Cells; Disease; Drug Formulations; Drug resistance; Effectiveness; Eosinophilia; Epitopes; Equilibrium; Fasciola; Fasciola hepatica; Fascioliasis; Food; Freund' s Adjuvant; Funding; Future; Goals; Goat; Hand; Health; Helminths; Hepatica; Human; ISCOMs; IgE; IgG1; Immune; Immune response; Immunity; Infection; Interleukin-12; Interleukin-4; Lead; Link; Liver; Measures; Mediating; Memory; Modeling; Morbidity - disease rate; Mus; NK-lysin; Oils; Oryctolagus cuniculus; Outcome; Parasites; Pharmaceutical Preparations; Production; Protein Family; Proteins; Research; Research Personnel; Role; Ruminants; Saposins; Sheep; T-Lymphocyte; Testing; Time; Treatment Cost; Trematoda; Vaccinated; Vaccination; Vaccines; base; bile duct; cytokine; disorder control; food security; immunogenic; improved; macrophage; mouse model; neglect; novel; pathogen; polypeptide; protective effect; response; theories; triclabendazole; vaccine efficacy

DESCRIPTION (provided by applicant): The helminth parasite Fasciola hepatica causes liver fluke disease or fascioliasis, thereby affecting the health of humans, as well as sheep, cattle and goats, among others mammalians. Fascioliasis causes losses in agriculture estimated at >US3.2billion per year. Fascioliasis is also a major zoonotic disease and it is estimated that 17 million people worldwide are infected. The flukicide triclabendazole is the most effective drug to control fascioliasis; however, the cost of treatment and the emergence of drug resistance in sheep infected with F. hepatica suggest a need to develop sustainable strategies, such as vaccination for the control of this disease. However, despite the long-standing research, a vaccine against Fasciola hepatica has not yet been developed. We have identified a novel F. hepatica antigen termed FhSAP2 that when delivered subcutaneously (SC) in Freund's complete adjuvant (FCA) is able to induce partial immunity (>60% reduction in parasite burden and significant reduction of liver damage) in rabbits and mice challenged with F. hepatica metacercariae. FhSAP2 is an 11.5kDa polypeptide belonging to the F. hepatica saposin-like / NK-lysin protein family. We also demonstrated that the immunity induced by the FhSAP2-FCA formulation is associated with high levels of IgG2a antibodies and high levels of IFN3, which are signatures of a Th1 immune response. These results led us to hypothesize that the protection induced by FhSAP2 is mediated by a mechanism linked to CD4+ Th1 cells, which is a new concept in the field of fascioliasis since F. hepatica, like most helminthes, is traditionally associated to Th2 immune responses. The goal of the present study is to study the modulation of T-helper 1, T- helper 2 responses and the protective effect against F. hepatica induced by FhSAP2 with these formulations in the mouse model of fascioliasis. To address this goal we propose to fulfill two specific aims in the 3-year funding period. In specific aim-1 we will study the protective effect of FhSAP2 when delivered SC in adjuvants containing immunostimulatory sequences. Specifically, we will ascertain whether the prime-boost strategy of naove C57BL/6 (H-2b) mice with FhSAP2 in MontanideTM ISM 1312 and ISA 70M or trapped into ISCOMs co- administered with IL-12 or CpG-ODN could mimic or enhance the protection levels obtained with FhSAP2 in CFA. This will lead to an optimization of the vaccine formulation for future studies. In the specific aim-2 we will study how the vaccine formulations used in the aim-1 modulate the T helper 1(Th1)-T helper 2 (Th2) responses. We will look at the Th1/Th2 cytokine profile, the levels of antibody subclasses as well as the activation status of B- and T-cells, macrophages (MX) and dendritic cells (DCs) elicited in naove mice and these parameters will be correlated with the levels of protection obtained in specific aim-1. The outcome will allow us to test our hypothesis of the protective role of Th1 responses in fascioliasis. If the proposed aims are achieved, we not only would have in hand an optimized vaccine formulation to be assayed in ruminants but we will also put forward a new concept of how to induce protection against F. hepatica, which will open the door to further studies to elucidate the immune mechanisms that make possible the Th1 immune responses which are effective against a multicellular fluke like F. hepatica. Moreover, these studies might serve as the basis for the application of this concept in the study of other neglected diseases caused by human liver fluke pathogens. The main objective of PI with this SC1 application is to make a transition to a non-SCORE support mechanism and in doing so establish herself as an independent competitive investigator. PUBLIC HEALTH RELEVANCE: Fasioliasis is a major disease of ruminants and more recently humans. We have demonstrated that an FhSAP2 antigen induces significant protection in a mouse and rabbit model of fascioliasis. We propose to optimize the vaccine formulation and improve the efficacy of the vaccine. In doing so in the future we will be able to evaluate the optimized vaccine in ruminants.

描述（由申请人提供）：Helminth寄生虫fasciola Hepatica引起肝氟疾病或筋膜病，从而影响人类的健康以及绵羊，牛和山羊等哺乳动物。筋膜症会导致每年估计> 32亿美元的农业损失。筋膜病也是一种主要的人畜共患病，据估计，全世界有1700万人被感染。 Flukicide Triclabendazole是控制筋膜病的最有效药物。但是，治疗成本和感染F. Hepatica的绵羊耐药性的出现表明，需要开发可持续的策略，例如控制这种疾病的疫苗接种。然而，尽管进行了长期的研究，但尚未开发针对Fasciola Hepatica的疫苗。 我们已经确定了一种称为FHSAP2的小说F. hepatica抗原，当在弗朗德的完整辅助（FCA）中皮下递送（SC）时，能够诱导部分免疫力（寄生虫负担降低> 60％，而在Rabbits造成的寄生虫负担降低，大量减少了肝脏损害），对F. hepatica Metaccercerae挑战的兔子损伤）。 FHSAP2是一种11.5KDA多肽，属于乙型乳糖蛋白酶蛋白家族。我们还证明了FHSAP2-FCA制剂诱导的免疫力与高水平的IgG2A抗体和高水平的IFN3有关，这是Th1免疫反应的特征。这些结果使我们假设FHSAP2诱导的保护是由与CD4+ Th1细胞相关的机制介导的，CD4+ TH1细胞是肌菌病领域的一个新概念，因为F. hepatica和大多数舵手一样，传统上与​​TH2免疫反应相关。本研究的目的是研究T-助手1，T-助手2响应的调节以及对FHSAP2诱导的F. hepatica的保护作用，并在小鼠筋膜病模型中使用这些配方。为了解决这个目标，我们建议在三年资金期间实现两个具体目标。在特定目标中，我们将研究FHSAP2的保护作用，当时在含有免疫刺激序列的佐剂中递送SC时。具体而言，我们将确定在Montanidetm ISM 1312和ISA 70m中使用FHSAP2的Naove C57BL/6（H-2B）小鼠的主要促进策略是，还是被困在与IL-12或CPG-ODN同时管理的ISCOMS中，可以模拟CFAA中的保护水平或增强保护水平。这将导致对未来研究的疫苗配方的优化。在特定的AIM-2中，我们将研究AIM-1中使用的疫苗配方如何调节T辅助1（TH1）-T辅助辅助2（TH2）响应。我们将研究Th1/Th2细胞因子谱，抗体亚类的水平以及B-和T-Cells，巨噬细胞（MX）和树突状细胞（DCS）的激活状态，这些参数将与在特定AIM-1中获得的保护水平相关。结果将使我们能够检验Th1反应在筋膜病中的保护作用的假设。 如果实现了拟议的目标，我们不仅将在反刍动物中进行测定的优化疫苗配方，而且我们还将提出一个新的概念，即如何诱导对肝螺旋藻的保护，这将为进一步的研究打开进一步的研究，以阐明可以使Th1免疫反应的免疫反应的免疫反应，从而有效地抵抗多发纤维化的Fluce f。此外，这些研究可能是该概念在研究其他被忽视的疾病中应用的基础。 使用此SC1应用程序的PI的主要目的是向非分数支持机制过渡，并这样做确定自己是独立的竞争研究者。 公共卫生相关性：fasioliasis是反刍动物和最近人类的主要疾病。我们已经证明，FHSAP2抗原在小鼠和兔子症模型中诱导了显着保护。我们建议优化疫苗配方并提高疫苗的功效。将来这样做，我们将能够评估反刍动物中优化的疫苗。