The development of probiotic yeast as an inexpensive vaccine delivery platform

益生菌酵母作为廉价疫苗输送平台的开发

• 批准号: 8572767
• 负责人: Tracey Jane Lamb
• 金额: $ 199.42万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-30 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8572767
• 关键词: Adjuvant; Antibiotics; Antigens; Area; Biological Assay; Cause of Death; Child; Chimeric Proteins; Cholera; Communicable Diseases; Cryptosporidium parvum; Developed Countries; Developing Countries; Development; Disease; Dose; Financial cost; Fusion Protein Expression; Gastrointestinal tract structure; Generations; Genetic Engineering; Genetic Techniques; Health; Helminths; Histocompatibility Antigens Class II; Immune; Immune response; Infection; Intervention; Longevity; Memory; Modeling; Mus; Nature; Oral; Oral Administration; Plasmablast; Probiotics; Regimen; Rotavirus; Saccharomyces cerevisiae; Surface; T memory cell; Technology; Vaccinated; Vaccination; Vaccines; Yeasts; antigen challenge; arm; cost effective; cytokine; gastrointestinal; infant morbidity/mortality; killings; large scale production; mouse model; mutant; novel; novel vaccines; pathogen; response; uptake; vaccine delivery

DESCRIPTION (provided by applicant): Infectious diseases of the gastrointestinal tract are a significant cause of infant mortality and morbidity in the developing world. Globally over 1 billio people are infected with gastrointestinal helminths and diarrheal disease is the second leading cause of death in children under 5, killing approximately 2 million children every year. Vaccination is one of the most cost-effective health interventions that can protect people from infection in endemic areas, saving millions of lives every year. Although vaccines currently exist to protect against infection with rotavirus and cholera, uptake of these vaccines in developing countries is poor due to the financial cost. Furthermore there is an urgent need for the development of new vaccines that provide protection against other diseases of the gastrointestinal tract. This proposal will develop a new affordable vaccine delivery platform that uses the probiotic yeast Saccharomyce cerevisiae boulardii to deliver vaccines directly to the gastrointestinal tract. Using genetic techniques already established for Saccharomyces cerevisiae I will genetically engineer S. boulardii to express antigens that induce protective immune responses fused to a novel adjuvant technology, ImmunobodiesTM. Oral administration of genetically transformed S. boulardii will facilitate expression of these fusion proteins in situat the mucosal surface. The generation of immune responses by antigen-ImmunobodyTM fusion proteins delivered by genetically transformed S. boulardii via oral vaccination will be initially demonstrated in mice using model antigen to describe the baseline immune responses generated by different dosing regimens. Co-administration of S. boulardii expressing mouse polarizing cytokines will facilitate the arming of different the immune effector mechanisms driven by Th1, Th2 or Th17 responses. This will be important because different types of pathogens require different immune effector mechanisms for clearance. I will also examine the longevity of the immune responses generated by this vaccine delivery platform by assaying for memory responses (plasmablasts and central memory T cells) in mice responding to antigen challenge. The protective nature of the immune responses generated will be demonstrated using a mouse model of diarrheal infection, Cryptosporidium parvum. Defined vaccine targets against C. parvum will be expressed by S. boulardii as ImmunobodyTM fusion proteins and the vaccinated mice challenged with Saccharomyce cerevisiae boulardii infection. Lastly I will generate auxotrophic mutants of S. boulardii to facilitate large-scale production of this vaccine delivery platform in developing countries removing the requirement for costly antibiotic selection. This project will radically change the way vaccines are administered both in developed and developing countries.

描述（由申请人提供）：胃肠道传染病是发展中国家婴儿死亡和发病的重要原因。全球有超过 10 亿人感染胃肠道蠕虫，腹泻病是 5 岁以下儿童的第二大死因，每年约有 200 万儿童死亡。疫苗接种是最具成本效益的健康干预措施之一，可以保护流行地区的人们免受感染，每年挽救数百万人的生命。尽管目前已有疫苗可以预防轮状病毒和霍乱感染，但由于经济成本，发展中国家对这些疫苗的使用率很低。此外，迫切需要开发新的疫苗来预防其他胃肠道疾病。该提案将开发一种新的负担得起的疫苗输送平台，该平台使用益生菌酿酒酵母布拉氏酵母将疫苗直接输送到胃肠道。利用已经为酿酒酵母建立的遗传技术，我将对布拉氏酵母进行基因改造，使其表达抗原，诱导与新型佐剂技术Immunobodies™融合的保护性免疫反应。口服转基因布拉氏酵母菌将促进这些融合蛋白在粘膜表面的表达。基因转化的布拉氏酵母通过口服疫苗递送的抗原-ImmunobodyTM 融合蛋白产生的免疫反应将首先在小鼠中使用模型抗原来证明，以描述不同给药方案产生的基线免疫反应。共同施用表达小鼠极化细胞因子的布拉氏酵母菌将促进由 Th1、Th2 或 Th17 反应驱动的不同免疫效应机制的武装。这很重要，因为不同类型的病原体需要不同的免疫效应机制来清除。我还将通过测定小鼠对抗原攻击的记忆反应（浆母细胞和中央记忆 T 细胞）来检查该疫苗递送平台产生的免疫反应的寿命。所产生的免疫反应的保护性质将通过腹泻感染隐孢子虫小鼠模型来证明。针对微小念珠菌的特定疫苗靶点将由布拉氏酵母表达为ImmunobodyTM 融合蛋白，并且接种疫苗的小鼠将受到酿酒酵母布拉氏酵母感染的攻击。最后，我将产生布拉氏酵母菌的营养缺陷型突变体，以促进该疫苗递送平台在发展中国家的大规模生产，从而消除昂贵的抗生素选择的要求。该项目将从根本上改变发达国家和发展中国家的疫苗管理方式。