Single cell trancriptomics to identify LTBI reactivation markers in TB/HIV co-infection

项目摘要 结核病的全球控制因同时感染人类免疫缺陷病毒（艾滋病毒）而变得更加复杂。 那些感染艾滋病毒的人有很高的风险重新激活潜伏性结核感染（LTBI）。病毒诱导的慢性免疫 CD 4 + T细胞的活化而不是仅仅耗竭与由于SIV共感染引起的LTBI再活化相关。 此外，组合抗逆转录病毒疗法（cART）不能恢复T效应子功能，从而防止LTBI 在TB/SIV共感染的非人灵长类动物模型中的再活化。研究cART对慢性 在单细胞水平的相关共感染临床前模型中的免疫激活将导致鉴定 预测LTBI再激活的关键生物标志物。 我们将协同这里提出的研究与资助的K 01奖，旨在收集有凝聚力的数据 来自存档对照样本（未感染、LTBI、SIV感染、Mtb/SIV共感染但未接受过cART;存档 样品）和Mtb/SIV共感染的短期、长期cART治疗的（K-award）恒河猴。基于 我们从合并感染研究中获得的发现，我们假设在Mtb/SIV合并病毒血症高峰期启动cART时， 感染导致免疫激活和巨噬细胞周转显着下降，它不能挽救歪斜的 导致LTBI再激活的CD 4 +T效应记忆应答。因此，在目标1中，我们将确定具体的 巨噬细胞和CD 4 + T细胞之间相互作用的谱系标志物，尽管有cART， Mtb/SIV共感染恒河猴。在目标2中，我们将研究SIV驱动的慢性炎症的最早期事件， 免疫激活，并将我们的发现与cART治疗的队列进行比较。为此，i）我们将比较激活 浆细胞样树突状细胞（pDC）和NK细胞在Mtb/SIV共感染中的状态，ii）我们将研究 cART对浆细胞样树突状细胞（pDC）驱动的I型干扰素（IFN）产生及其对 与未处理的对照相比的下游效应器反应。 总体而言，我们将能够确定i）巨噬细胞周转是否干扰CD 4 + T细胞恢复， 功能，ii）如果cART通过改善NK细胞活性有效地控制病毒驱动的免疫激活的最早事件， 功能和iii）cART对I型IFN应答在驱动Mtb/SIV共感染中的免疫活化的影响。 感染研究cART对Mtb/SIV合并感染中免疫激活的影响对于识别 用于治疗和疫苗设计的生物标志物，以防止LTBI再活化。

Project Summary The global control of tuberculosis (TB) is compounded by co-infection with Human Immunodeficiency Virus (HIV). Those infected with HIV are at high risk of reactivating latent TB infection (LTBI). Viral-induced chronic immune activation rather than mere depletion of CD4+ T cells correlates with LTBI reactivation due to SIV co-infection. Further, combinatorial antiretroviral therapy (cART) fails to restore T-effector functions and thus prevent LTBI reactivation in a nonhuman primate model of TB/SIV co-infection. Investigating the impact of cART on chronic immune activation in a relevant co-infected preclinical model at the single cell level will lead to the identification of key biomarkers predicting LTBI reactivation. We will synergize the research proposed here with a funded K01-award aims to collect cohesive data from archived control samples (uninfected, LTBI, SIV infected, Mtb/SIV co-infected but cART naïve; archived samples) and Mtb/SIV co-infected short-term, long-term cART treated (K-award) rhesus macaques. Based on our findings from the co-infection study, we hypothesize that while initiating cART at peak viremia in Mtb/SIV co- infection causes a significant decline in immune activation and macrophage turnover, it fails to rescue the skewed CD4+T effector memory responses leading to LTBI reactivation. Thus, in Aim 1, we will identify the specific lineage markers in the interplay between macrophages and CD4+ T cells that remain impaired despite cART in Mtb/SIV co-infected rhesus macaques. In Aim 2, we will investigate the earliest events of SIV-driven chronic immune activation and compare our findings to cART treated cohorts. For this, i) we will compare the activation status of plasmacytoid dendritic cells (pDCs) and NK cells in Mtb/SIV co-infection, ii) we will study the impact of cART on plasmacytoid dendritic cell (pDC)-driven Type-I Interferon (IFN) production and its impact on downstream effector responses compared to untreated controls. Overall, we will be able to determine if i) macrophage turnover interferes with CD4+ T cell restoration and function, ii) if cART effectively controls the earliest events of virus-driven immune activation by improving NK cell function and iii) the impact of cART on Type-I IFN response in driving the immune activation in Mtb/SIV co- infection. Studying the impact of cART on immune activation in Mtb/SIV co-infection is critical to identifying biomarkers for therapeutics and vaccine design to prevent LTBI reactivation.