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

结核分枝杆菌(Mtb)是人类与传染病相关的主要死亡原因。 全球艾滋病毒携带者。要实现全球结核病，需要较短的结核病治疗方案 淘汰赛。目前为期6个月的结核病治疗过程旷日持久，反映了一名 持续细菌亚群通过各种途径保持生长受限、对抗生素耐受的状态 适应性策略，包括诱导严格反应。关键的严格反应酶RelMtb 对于结核分枝杆菌在体外和动物肺中在生理相关压力下的长期存活至关重要。 最近，我们研制出一种治疗性的relMtb DNA疫苗，它可以诱导RelMtb特异性的细胞免疫， 并显著增强一线药物异烟肼在小鼠体内抗活动性结核病的活性。我们还有 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MIP3α，显著增强抗原特异性T细胞反应。在 目前的提案，我们将确定这一IDC靶向策略，以及一种前景看好的新佐剂 使用环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 验证一种新的假设，即增强对RelMtb的细胞免疫会增强第一个- 在标准的小鼠结核病模型中，LINE抗结核方案并加速治愈。由于艾滋病毒感染是 与T细胞稳态紊乱有关，包括CD4+T细胞耗尽和持续扩增 CD8+T细胞，我们将表征这些细胞类型中的每一种对 在小鼠体内接种relMtb DNA疫苗。为了将我们的发现转化到临床环境中，我们接下来将测试 这种免疫策略在产生免疫反应模式的恒河猴中的免疫原性 与人类的非常相似。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 在一线抗结核治疗中，我们将测量在结核病治疗过程中RelMtb特异性T细胞反应。这 该提案代表了在微生物学方面拥有重要专业知识的研究人员之间的独特合作， 分子生物学、免疫学、DNA疫苗和动物模型。我们的发现预计会有更多的- 对开发新的辅助疗法以缩短持续时间的影响 对药物敏感和耐药结核病的治疗，以及确认 艾滋病毒感染者和非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.