Therapeutic vaccination to augment stringent response-specific T-cell immunity to MTB persisters

结核分枝杆菌（Mtb）是导致人类死亡的主要传染病相关原因 艾滋病病毒感染者需要更短的结核病治疗方案，以实现全球结核病 淘汰目前6个月结核病疗程的长期性质反映了结核病治疗的独特能力， “持久”细菌的亚群通过各种途径保持在生长受限的、耐药性的状态， 适应性策略，包括严格反应的诱导。关键的严格反应酶RelMtb 是体外和动物肺中在生理相关应激下Mtb长期存活所必需的。 最近，我们已经产生了治疗性relMtb DNA疫苗，其诱导RelMtb特异性细胞免疫， 并显著增强一线药物异烟肼在小鼠中抗活动性TB的活性。我们也有 开发了一种新的疫苗接种策略，包括将感兴趣的抗原与未成熟的树突状细胞融合， 细胞（iDC）靶向趋化因子MIP 3 α，可显著增强抗原特异性T细胞应答。在 目前的建议，我们将确定这种iDC靶向策略，以及一种有前途的新佐剂， 涉及使用环状二核苷酸激活干扰素基因刺激物（STING）的方法 途径，增强我们的relMtb DNA疫苗的免疫原性。理想的疫苗平台将用于 测试新的假设，即增强的针对RelMtb的细胞免疫增强了第一- 线抗TB方案和加速治愈的标准鼠模型的TB。由于艾滋病毒感染是 与T细胞稳态紊乱相关，包括CD 4 + T细胞耗竭和CD 4 + T细胞持续扩增。 在CD 8 + T细胞中，我们将表征这些细胞类型中的每一种对CD 8 + T细胞的治疗功效的贡献。 小鼠中的relMtb DNA疫苗。为了将我们的发现转化为临床环境，我们将在接下来的实验中测试 这种疫苗接种策略在恒河猴中免疫原性，恒河猴产生免疫应答模式 最类似于人类。最后，利用可通过 南非HIV感染和未感染肺结核患者接受治疗的纵向队列研究 一线抗结核治疗，我们将测量结核治疗期间RelMtb特异性T细胞应答。这 该提案代表了在微生物学方面具有重要专业知识的研究者之间的独特合作， 分子生物学、免疫学、DNA疫苗和动物模型。我们的发现有望对- 达到新的连续治疗的发展，缩短持续时间的影响， 药物敏感和耐药结核病的治疗，以及用于确认 艾滋病毒感染者和未感染者结核病治疗的充分性。

Mycobacterium tuberculosis (Mtb) is the leading infectious disease-related cause of death among people living with HIV worldwide. Shorter tuberculosis (TB) treatment regimens are needed to achieve global TB elimination. The protracted nature of the current 6-month TB treatment course reflects the unique ability of a subpopulation of “persister” bacteria to remain in a growth-limited, antibiotic-tolerant state through various adaptive strategies, including induction of the stringent response. The key stringent response enzyme RelMtb is essential for long-term Mtb survival under physiologically relevant stresses in vitro and in animal lungs. Recently, we have generated a therapeutic relMtb DNA vaccine, which induces RelMtb-specific cellular immunity, and significantly augments the activity of the first-line drug isoniazid against active TB in mice. We also have developed a novel vaccination strategy involving fusion of the antigen of interest with the immature dendritic cell (iDC)-targeting chemokine MIP3α, which significantly enhances antigen-specific T-cell responses. In the current proposal, we will determine if this iDC-targeting strategy, as well as a promising new adjuvant approach involving the use of cyclic dinucleotides to activate the stimulator of interferon genes (STING) pathway, enhance the immunogenicity of our relMtb DNA vaccine. The ideal vaccine platform will be used to test the novel hypothesis that enhanced cellular immunity against RelMtb potentiates the activity of the first- line anti-TB regimen and accelerates cure in the standard murine model of TB. Since HIV infection is associated with disturbed T-cell homeostasis, including depletion of CD4+ T cells and persistent expansion of CD8+ T cells, we will characterize the contribution of each of these cell types to the therapeutic efficacy of the relMtb DNA vaccine in mice. In order to transition our findings to the clinical setting, we will next test the immunogenicity of this vaccination strategy in rhesus macaques, which develop immune response patterns most analogous to those of humans. Finally, leveraging archived clinical samples available through the RePORT South Africa longitudinal cohort of HIV-infected and uninfected patients with pulmonary TB receiving first-line anti-tubercular treatment, we will measure RelMtb-specific T-cell responses during TB therapy. This proposal represents a unique collaboration between Investigators with significant expertise in microbiology, molecular biology, immunology, DNA vaccines, and animal models. Our findings are expected to have far- reaching implications for the development of novel adjunctive therapies for shortening the duration of treatment for drug-susceptible and drug-resistant TB, as well as novel diagnostic tools for confirming the adequacy of TB treatment in HIV-infected and uninfected individuals.