Project 2: Leveraging microbial ecology to define novel Clostridioides difficile mRNA vaccine targets

摘要--项目2(抗原发现) 艰难梭菌是一种能引起多种胃肠道(GI)疾病的芽胞形成病原体 严重程度不一，从轻度腹泻到暴发性结肠炎和死亡。在治疗感染方面遇到的困难 常规抗生素和不断增加的复发率突出表明有必要发展 应对这一紧迫的公共卫生威胁的新治疗战略。迄今为止，艰难梭菌的疫苗还没有 完全满足这一需要，因此未来的战略将需要创新的方法，以限制疾病和促进 清除这种病原体。我们的目标是建立一条管道，以识别C。 困难菌细胞和孢子表面，并将其开发为下一代抗病毒的多价mRNA疫苗 艰难梭菌。抗原发现战略将包括艰难梭菌生命周期的各个方面，抗原变异 细胞表面和微生物生态。我们假设艰难梭菌蛋白的详细特征和 对受感染肠道的适合性和与常驻微生物群的竞争至关重要的基因系统将导致 验证高效的新疫苗靶点。我们的方法将使用全基因组序列(WGS) 广泛的医院和社区相关菌株的表面蛋白质组分析和深入 研究感染过程中的代谢相关因素。我们将结合先进的成像质谱学 (IMS)、小鼠感染模型和确定艰难梭菌感染期间营养需求的遗传学 并针对这些表面暴露的蛋白进行mRNA-LNP疫苗接种。总之，这项工作将产生一个 利用微生物生态学发现新的疫苗靶标以根除疟疾的翻译工作流 艰难梭菌。

SUMMARY - PROJECT 2 (ANTIGEN DISCOVERY) Clostridium difficile is a spore-forming pathogen that causes a wide range of gastrointestinal (GI) disorders varying in severity from mild diarrhea to fulminant colitis and death. Difficulties in treating infections with conventional antibiotics and increasing rates of recurrent infection underscore the need for the development of new therapeutic strategies to combat this urgent public health threat. To date vaccines for C. difficile have not fully met this need, thus future strategies will require innovative approaches that limit disease and promote clearance of this pathogen. Our objective is to generate a pipeline to identify novel vaccine antigens on the C. difficile cell and spore surface and develop these as the next generation of multi-valent mRNA vaccines against C. difficile. Antigen discovery strategy will incorporate aspects of the C. difficile life cycle, antigen variation on the cell surface, and microbial ecology. We hypothesize that detailed characterization of C. difficile proteins and gene systems important for fitness in the infected gut and competition with the resident microbiota will lead to validation of highly effective new vaccine targets. Our approach will use whole genome sequence (WGS) and surface proteome analyses on a wide array of hospital and community-associated strains and in-depth investigation into metabolic correlates during infection. We will combine advanced imaging mass spectrometry (IMS), mouse models of infection, and genetics to define nutritional requirements for C. difficile during infection and target these surface exposed proteins for mRNA-LNP vaccination. Together, this work will generate a translational workflow that leverages microbial ecology for discovery of novel vaccine targets for eradication of C. difficile.