A novel c-di-AMP-based recombinant BCG vaccine

一种新型基于 c-di-AMP 的重组卡介苗疫苗

• 批准号: 10667007
• 负责人: Guangchun Bai
• 金额: $ 24.45万
• 依托单位: ALBANY MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-09 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10667007
• 关键词: Adjuvant; Animals; Antibodies; Antigens; Attenuated Vaccines; BCG Vaccine; Bacillus; Bacterial Physiology; Biological; CD8-Positive T-Lymphocytes; Cells; Dinucleoside Phosphates; Enzyme-Linked Immunosorbent Assay; Epidemic; Etiology; Generations; Genes; Goals; Homeostasis; Immune response; In Vitro; Infant; Interferon Type I; Knowledge; Licensing; Link; Listeria monocytogenes hlyA protein; Lung; Lung infections; Macrophage; Mediating; Modeling; Mus; Mycobacterium bovis; Mycobacterium tuberculosis; Mycobacterium tuberculosis antigens; Natural Immunity; Outcome; Pathogenesis; Periodicity; Play; Population; Prevention; Production; Proteins; Public Health; Recombinant Vaccines; Reporting; Role; Signal Transduction; Signaling Molecule; Spleen; T cell response; Testing; Tuberculosis; Tuberculosis Vaccines; Vaccinated; Vaccination; Vaccine Adjuvant; Vaccines; Virulence; Virulent; Western Blotting; adaptive immunity; cytokine; design; draining lymph node; epidemic response; experimental study; immunogenicity; improved; insight; mutant; novel; novel strategies; novel vaccines; pathogen; pathogenic bacteria; phosphoric diester hydrolase; rBCG; regional difference; response; vaccination against tuberculosis; vaccine efficacy; vaccine platform; vaccine strategy

SUMMARY Tuberculosis (TB) remains a global epidemic, with one-fourth of the current world population infected and approximately 10 million new active cases annually. However, our knowledge about the causative agent, Mycobacterium tuberculosis (Mtb), is still limited, and the only licensed TB vaccine (BCG) is inadequate to control the epidemic. It is critical to better understand the biological difference between Mtb and BCG in order to develop a more effective TB vaccine. Our long-term goal of this project is to develop a novel recombinant BCG vaccine to better control TB. Recently, cyclic di-AMP (c-di-AMP) has been recognized as a new bacterial signaling molecule and a potent vaccine adjuvant. We have demonstrated that Mtb Rv3586 (disA) encodes a diadenylate cyclase and Rv2837c (cnpB) encodes a c-di-AMP phosphodiesterase. Compared to the Mtb wild-type (WT), ∆cnpB secretes a significantly larger amount of c-di-AMP and stimulates a stronger type I interferon (IFN-I) response in the infected macrophages. We have also revealed that BCG ∆cnpB produces but does not secrete c-di-AMP; both c-di-AMP secretion and Mtb region of difference 1 (RD1) are required for the c-di-AMP-induced IFN-I response. Interestingly, it is well known that BCG is defective in inducing IFN-I, and addition of IFN-I enhances BCG's immunogenicity. Moreover, c-di-AMP has been utilized as a potential vaccine adjuvant that elicits strong humoral and cellular immune response. Overproduction of c- di-AMP in BCG by expressing disA also results in better protection in infected animals. However, the improvement is moderate likely because that the recombinant BCG is still unable to secrete c-di-AMP and induce substantial IFN-I. Therefore, we hypothesize that manipulation of c-di-AMP homeostasis and secretion in BCG will enable BCG to provide a better protection against TB. The objective of this application is to construct a recombinant BCG that secretes c-di-AMP and induces optimal levels of IFN-I response during vaccination. We propose two specific aims: (1) to construct c-di-AMP-secreting recombinant BCG strains, and (2) to evaluate the recombinant BCG strains in induction of IFN-I and protection against Mtb infection. These recombinant BCG strains will be very likely superior to the current BCG in vaccine efficacy. Furthermore, our findings will also provide fundamental insights into vaccine strategies for other bacterial pathogens. Thus, this proposal has a broad impact on public health.

概括 结核病 (TB) 仍然是一种全球流行病，目前世界人口的四分之一受到感染， 每年大约有 1000 万新的活跃病例，但是，我们对病原体的了解， 结核分枝杆菌 (Mtb) 的数量仍然有限，唯一获得许可的结核疫苗 (BCG) 不足以 为了控制疫情，更好地了解 Mtb 和 BCG 之间的生物学差异至关重要。 开发更有效的结核病疫苗 我们该项目的长期目标是开发一种新型疫苗。 重组卡介苗可更好地控制结核病 最近，环二-AMP（c-di-AMP）已被认为是一种有效的疫苗。 我们已经证明 Mtb Rv3586 是一种新的细菌信号分子和有效的疫苗佐剂。 (disA) 编码二腺苷酸环化酶，Rv2837c (cnpB) 编码 c-di-AMP 磷酸二酯酶。 与 Mtb 野生型 (WT) 相比，ΔcnpB 分泌显着大量的 c-di-AMP 并刺激 我们还发现，卡介苗在受感染的巨噬细胞中具有更强的 I 型干扰素 (IFN-I) 反应。 ΔcnpB 产生但不分泌 c-di-AMP；同时分泌 c-di-AMP 和差异 1 (RD1) 的 Mtb 区域 是 c-di-AMP 诱导的 IFN-I 反应所必需的，众所周知，BCG 在 IFN-I 方面存在缺陷。 诱导IFN-I，并且添加IFN-I增强BCG的免疫原性此外，已经利用了c-di-AMP。 作为潜在的疫苗佐剂，可引发强烈的体液和细胞免疫反应。 通过在 BCG 中表达 disA，di-AMP 也可以对受感染的动物产生更好的保护。 改善程度中等，可能是因为重组 BCG 仍然无法分泌 c-di-AMP，并且 诱导大量的 IFN-I 因此，我们追求 c-di-AMP 稳态和分泌的操纵。 BCG 将使 BCG 能够提供更好的预防结核病的保护作用。 构建重组 BCG，其分泌 c-di-AMP 并诱导最佳水平的 IFN-I 反应 我们提出了两个具体目标：（1）构建分泌c-di-AMP的重组BCG菌株，以及 (2)评价重组卡介苗菌株诱导IFN-I和对抗Mtb感染的保护作用。 此外，重组卡介苗菌株的​​疫苗功效很可能优于目前的卡介苗。 研究结果还将为其他细菌病原体的疫苗策略提供基本见解。 该提案对公共卫生产生广泛影响。