"Subunit Vaccines for Brucella Pathogens"

描述(申请人提供)：布鲁氏菌属B类制剂，是高度传染性的革兰氏阴性菌，已被确定为潜在的生物武器。布鲁氏菌病是通过摄入未经巴氏灭菌的乳制品自然传播的，表现为类似流感的系统，尽管接受了抗生素治疗，但仍可导致反复发作的后遗症，明显表现为波浪热和关节炎。布鲁氏菌在宿主体内的存活与其抵抗细胞内识别的能力有关，从而使它们能够隔离在各种组织中。到目前为止，还没有对人类有效的疫苗，但保护依赖于细胞介导的免疫，特别是涉及肿瘤坏死因子-α和干扰素-α。能够概括这种反应的疫苗应该被证明在解决布鲁氏菌感染方面是有效的。两种推定的多胺结合蛋白，PotD和PotF，当与ISCOMS和CpG配方时，在用强毒力马利特氏杆菌16M株非肠道攻击的小鼠中，获得了相当于羊布鲁氏菌活疫苗的免疫保护。这种水平的保护(组织定植的对数减少)还没有用亚单位疫苗方法显示出来。考虑到这种疫苗配方的效力，我们正准备测试这些疫苗对非肠道和肺部感染、流产和猪瘟的有效性。因此，我们推测，由PotD和PotF组成的适当配方的疫苗，加上适合人类使用的佐剂，将提供对肠外和肺部布鲁氏菌攻击的保护。将多胺结合蛋白确定为疫苗靶标最终可能进一步适用于其他A类和B类病原体。为了进一步推动这一努力，针对特定目标1的研究将优化布鲁氏菌疫苗PotD和PotF的剂量和路线，以提供对非肠道和肺性羊瘟杆菌挑战的保护，并开发保护性免疫的相关性。针对特定目标2的研究将优化与PotD和PotF结合时的佐剂剂量，以提供针对非肠道和雾化白僵菌、流产白僵菌和猪白僵菌攻击的最佳保护。具体目标3的研究将在山羊布鲁氏菌病动物模型中测试PotD和PotF疫苗的有效性，以确定它们是否有能力保护山羊免受羊布鲁氏菌定居和流产的黏膜挑战。具体目标4的研究将评估GLP制备的PotD和PotF亚单位疫苗的各种安全参数。因此，这些研究将表明，当适当地提供亚单位疫苗时，可以预防肠外和肺部布鲁氏菌的挑战。 项目叙述布鲁氏菌病可能是一种使人虚弱的疾病，需要延长抗生素治疗来清除布鲁氏菌；然而，尽管进行了治疗，布鲁氏菌仍然可以持续存在。因此，研究的重点是开发布鲁氏菌病亚单位疫苗，并验证该疫苗制剂对两种敏感动物宿主和三种布鲁氏菌的保护效果。这项工作的总体目标是推进我们的疫苗研究，并在人体试验之前完成许多临床前研究。

DESCRIPTION (provided by applicant): Brucella species, members of Category B agents, are highly infectious Gram-negative bacteria that have been identified as potential biological weapons. Brucellosis is naturally transmitted via ingestion of unpasteurized dairy products, manifesting with flu-like systems and, despite antibiotic treatment, can cause a recurring sequelae, evident as undulant fever and arthritis. Brucellae survival within the host is linked to its ability to resist intracellular recognition, thus, allowing them to sequester in various tissues. To date, there are no effective vaccines for humans, but protection is cell-mediated immunity-dependent, particularly, involving TNF-a and IFN-?. Vaccines that can recapitulate such responses should prove effective in resolving Brucella infections. Two putative polyamine-binding proteins, PotD and PotF, when formulated with ISCOMs plus CpG, conferred immune protection equivalent to the live Rev-1 Brucella melitensis vaccine in mice parenterally challenged with virulent B. melitensis 16M strain. This level of protection (>4 log reduction in tissue colonization) has yet to be shown using a subunit vaccine approach. Given the potency of this vaccine formulation, we are uniquely poised to test the efficacy of these vaccines against parenteral and pulmonary B. melitensis, B. abortus, and B. suis challenges. Thus, we hypothesize that an appropriately formulated vaccine composed of PotD and PotF, combined with a suitable adjuvant for human use, will confer protection against parenteral and pulmonary Brucella challenge. Identifying polyamine-binding proteins as vaccine targets could eventually be further adapted for other Category A and B pathogens. To further this effort, studies in Specific Aim 1 will optimize the dosage and route for Brucella vaccines, PotD and PotF, to confer protection against parenteral and pulmonary B. melitensis challenges and develop correlates for protective immunity. Studies in Specific Aim 2 will optimize the dosage for adjuvant when combined with PotD and PotF to confer optimal protection against parenteral and aerosolized B. melitensis, B. abortus, and B. suis challenges. Studies in Specific Aim 3 will test the efficacy of PotD and PotF vaccines in a caprine brucellosis animal model for their ability to confer protection against mucosally challenged goats for B. melitensis colonization and abortion. Studies in Specific Aim 4 will evaluate various safety parameters for GLP- prepared PotD and PotF subunit vaccines. Thus, these studies will show that subunit vaccines, when appropriately delivered, can protect against parenteral and pulmonary Brucella challenges. PROJECT NARRATIVE Brucellosis can be a debilitating disease, requiring extended antibiotic treatment to clear the brucellae; yet, despite treatment, brucellae can still persist. Thus, studies focused on developing a subunit vaccine for brucellosis and validating the protective efficacy of this vaccine formulation in two susceptible animal hosts and against three species of Brucella. The overall goals of this work are to forward the studies for our vaccines and have many of the preclinical studies completed prior to testing in humans.