Immunoregulation /Immune Recognition In Filarial/Nonfilarial Parasitic Infection

丝虫/非丝虫寄生虫感染中的免疫调节/免疫识别

• 批准号: 8745274
• 负责人: Thomas Nutman
• 金额: $ 88.93万
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8745274
• 关键词: 70-kDa Ribosomal Protein S6 Kinases; Acute; Aerosols; Agonist; Antigen-Presenting Cells; Antigens; Bystander Effect; CCL11 gene; CCR1 gene; CD14 gene; CD3 Antigens; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CD8B1 gene; Cell physiology; Cells; Chronic; Clinical; Cook Islands; Cryopreserved Cell; Cyclophilins; Data; Dendritic Cells; Development; Disease; Ecuador; Epidemiology; Eukaryotic Initiation Factor-2; FCGR3B gene; Filarial Elephantiases; Flow Cytometry; Functional disorder; Gene Expression; Gene Expression Profile; Gene Expression Profiling; Genetic; Goals; Growth; HIV; Helminths; Homologous Gene; Human; IL2RB gene; IL7R gene; IRF1 gene; Immune; Immune response; Immunity; Immunologics; In Vitro; India; Individual; Infection; Infection prevention; Inflammatory; Interferon Type II; Interferons; Interleukin-10; Interleukin-12; Intestines; Legal patent; Life; Loiasis; Lung; Lymphatic; Macrophage Activation; Malaria; Mali; Mediating; Memory; Microfilaria; Molecular Profiling; Mus; Mycobacterium tuberculosis; Mycobacterium tuberculosis antigens; Myelogenous; Onchocerciasis; Outcome; Parasite Control; Parasites; Parasitic infection; Pathway interactions; Patients; Phenotype; Play; Population; Process; Production; Proliferating; Regulation; Regulatory T-Lymphocyte; Research; Role; Seasons; Signal Pathway; Signal Transduction; Site; Stem cells; System; T cell response; T memory cell; T-Cell Proliferation; T-Lymphocyte; TLR3 gene; TLR4 gene; Tuberculosis; Viral Tumor Antigens; Virulent; Virus Diseases; WISP3 gene; Work; anergy; base; chemotherapy; cytokine; effective therapy; exposed human population; filaria; immunoregulation; in vivo Model; interleukin-19; liquid chromatography mass spectrometry; mTOR protein; macrophage; member; monocyte; mycobacterial; prevent; protein expression; response; transcription factor; transmission process

The hallmark of the immune response seen in individuals with patent lymphatic filariasis is a profound inability to proliferate or produce cytokines associated with a Type 1 response (IL 2 and IFN γ) in response to parasite antigen. This parasite specific anergy is mediated, in large part, by IL 10 with TGF β and CTLA-4 playing smaller regulatory roles. Other members of the IL-10 superfamily (IL-19 and IL-24) have been now shown to be upregulated in patent LF, a process driven by IL-10 itself. The mechanisms underlying the modulation of parasite-specific responses in LF continues to be a major research question. Using multiparameter flow cytometry, this antigen-specific modulation was shown to be associated with an expansion of IL-10 producing adaptive Treg and altered development of parasite-specific central and effector memory T cell populations 4. We have demonstrated that these Tregs influence both effector T cells and antigen presenting cells (APCs), but alter APC function indirectly through the effector T cells (Metenou et al, submitted). Most recently, we have identified, using protein expression profiling (by LC/MS/MS) of nTregs in the context of filarial infection, 2 additional molecules (WISP3 and PSG-1) that are secreted by nTregs that suppress T cell proliferation and IFN−γ production by effector T cells in a contact independent manner. Not only has patent filarial infection been shown to modulate T cell responses, but it has also been shown to result in profound monocyte dysfunction (review here) that can be reversed by effective treatment with anti-filarial chemotherapy. Subsequently we have shown that LF induces an immunoregulatory population of monocytes that appear to be human parallels of alternatively activated macrophages. In addition, LF is associated with an expansion of CCR1 low circulating myeloid DCs 6 suggesting the myeloid populations may be of great import in the modulation of filarial-specific T cell function. Expansion of a non-classical (CD16hi) monocyte subset has very recently been identified in LF. Moreover, we have shown that in human monocytes populations the major 2 subsets (CD14+CD16- and CD14+CD16lo) have a clearly differential response to microfilariae (Mf) 7, the latter preferentially producing the regulatory cytokine IL-10. Using human monocyte derived dendritic cells (DC), we have explored the mechanisms by which parasite products alter the function of human APCs. Having previously shown that mf-derived soluble products interfere directly with TLR3 and TLR4 signaling pathways, we were next able to demonstrate that parasite products profoundly modulated the DCs ability to produce IL-12, CCL10 and CCL11 8 in response to antigen or TLR agonists. By using approaches to silence important transcription factors, we were able to demonstrate the parasite-induced diminution of IRF-1 in DCs dramatically alters IL-12 production thereby preventing INF-γ (and other Th1-associated) responses in LF 9. Moreover, using global protein expression profiling comparisons between Mf-exposed or unexposed human mDCs, mf significantly downregulated the mammalian target of rapamycin (mTOR) and the eukaryotic initiation factor (eIF) 2, eIF4 and p70S6K. Interestingly, live mf produce and secrete homologues of human FKBP1 (cyclophilin) a negative regulator of mTOR signaling. The effect of chronicity of infection per se on the T cell response to filarial infection has been studied by an exhaustive comparison of gene expression between cells purified from those with lifelong filarial infection and those expatriates with relatively acute infection. Using gene expression profiling, we were able to show that longstanding filarial infection (based on global gene expression ex vivo) showed a markedly down-regulated pattern of gene expression most notably in CD8+ cells but also in CD4+cells/ In a study that has taken advantage of cells cryopreserved from well characterized individuals from the Cook Islands where W. bancrofti is endemic, we have utilized multiparameter flow to demonstrate not only a diminished number of central memory cells (CD4+CCR7+CD127+CD27+CD45RA-) in chronically infected patients but also an increase number of revertant memory cells (CD3+ CD45RA+CCR7-CD127+CD122+) suggesting that chronicity in helminth infection (like in chronic viral infection) may predispose to memory cell dysfunction. Because chronic filarial (and other helminth) infections may alter immune reactivity to other (non-parasite) antigens and because these alterations may have profound implications for the clinical outcome of these non-filarial infections, collaborative studies in India, Mali, and Ecuador have shown that the presence of active filarial infection and/or chronic intestinal helminth infection very clearly blunts the Type 1 (and Th17) response to non-filarial antigens in the context of co-infection. Over the past four years, we have focused on the influence of pre-existing helminth infections on Mycobacterium tuberculosis (Mtb), malaria, and HIV. As a first step in examining the interaction between Mtb and filarial infection and based on the epidemiology of filarial/Mtb coinfection, an in vitro system of co infection was established and used to demonstrate that pre-exposure of human DCs and macrophages to live filarial parasites induces immunoregulatory phenotypes that alters mycobacterial entry and replication (Chatterjee, unpublished). Concurrently, we developed an in vivo model in which we rendered mice microfilaremic and then infected them (by aerosol) with virulent Mtb. Our data very clearly suggests that microfilaremia induces alternative activation of macrophages in the lung but fails to alter the growth or clearance of Mtb; microarray data from the lungs of these mice suggest a generalized modulation of interferon-gamma and IFN-γ regulated pathways (Chatterjee, Talaat, unpublished). Human studies ex vivo focusing more on latent tuberculosis in filarial-infected and -uninfected individuals have demonstrated that filarial infections: 1) modulate TLR expression and function in response to Mtb antigens 12; 2) markedly alter the Mtb-specific Th1/Th17 responses so important in maintaining latency through the concerted actions of CTLA-4 and PD-1 2; and 3) induce a population of Tregs that modulate Th17 responses in patients with latent Mtb infection 13. We have now extended these studies by developing multiparameter flow cytometric approaches to identify Mtb-specific stem cell memory (SCM) CD4+ and CD8+ T cells and are exploring the relationship between chronic filarial antigen exposure and the alteration in Mtb-specific memory In studies in Mali that have combined clinical and immunological aspects of malaria and filarial co-infection, our immunologically-focused studies have explored the bystander effects of pre-existing filarial infections on the response to malarial antigens longitudinally (before, during, and following the malarial transmission season). In two studies performed in different sites two years apart, we have shown quite conclusively that the presence of filarial infection modulates the innate (TLR-mediated) response to malarial antigens; more importantly, however, we have shown that filarial infection modulates malaria-specific Type 1 cytokine responses in an IL-10 dependent manner in a filaria/malaria co-infected population. We have identified the cell populations regulating the malaria-specific pro-inflammatory cytokine pathways in the co-filarial/malaria co-infected populations, and we have also demonstrated that filarial infections prevent almost completely the induction of malaria-specific polyfunctional T cells. Furthermore, we have demonstrated the pivotal role played by IRF-1 in the modulation of the malaria-specific Th1/Th17 responses.

淋巴丝虫病患者的免疫反应的特点是无法增殖或产生与响应寄生虫抗原的 1 型反应（IL 2 和 IFN γ）相关的细胞因子。这种寄生虫特异性无反应性在很大程度上是由 IL 10 介导的，而 TGF β 和 CTLA-4 则发挥较小的调节作用。 IL-10 超家族的其他成员（IL-19 和 IL-24）现已显示在专利 LF 中上调，这是由 IL-10 本身驱动的过程。 LF 中寄生虫特异性反应的调节机制仍然是一个主要的研究问题。 使用多参数流式细胞术，这种抗原特异性调节被证明与产生适应性 Treg 的 IL-10 扩增有关，并改变了寄生虫特异性中枢和效应记忆 T 细胞群的发育4。我们已经证明，这些 Tregs 影响效应 T 细胞和抗原呈递细胞 (APC)，但通过效应 T 细胞间接改变 APC 功能（Metenou 等人提交）。最近，我们利用丝虫感染背景下 nTreg 的蛋白表达谱（通过 LC/MS/MS）鉴定了 nTreg 分泌的另外 2 种分子（WISP3 和 PSG-1），它们以接触独立的方式抑制 T 细胞增殖和效应 T 细胞产生 IFN−γ。 丝虫感染不仅被证明可以调节 T 细胞反应，而且还被证明会导致严重的单核细胞功能障碍（查看此处），这种功能障碍可以通过抗丝虫化疗的有效治疗来逆转。随后我们发现 LF 诱导了免疫调节单核细胞群，这些单核细胞似乎与人类替代激活的巨噬细胞相似。此外，LF 与 CCR1 低循环髓样 DC 的扩增相关 6 表明髓样细胞群可能在丝虫特异性 T 细胞功能的调节中具有重要意义。最近在 LF 中发现了非经典 (CD16hi) 单核细胞亚群的扩增。此外，我们已经表明，在人类单核细胞群体中，主要的 2 个亚群（CD14+CD16- 和 CD14+CD16lo）对微丝蚴 (Mf) 7 具有明显不同的反应，后者优先产生调节性细胞因子 IL-10。 使用人类单核细胞衍生的树突状细胞 (DC)，我们探索了寄生虫产物改变人类 APC 功能的机制。之前已经表明，mf 衍生的可溶性产物直接干扰 TLR3 和 TLR4 信号通路，接下来我们能够证明寄生虫产物深刻调节 DC 响应抗原或 TLR 激动剂产生 IL-12、CCL10 和 CCL11 8 的能力。 通过使用沉默重要转录因子的方法，我们能够证明寄生虫诱导的 DC 中 IRF-1 的减少会显着改变 IL-12 的产生，从而阻止 LF 9 中的 INF-γ（和其他 Th1 相关）反应。此外，使用 Mf 暴露或未暴露的人类 mDC 之间的全局蛋白表达谱比较，mf 显着下调雷帕霉素的哺乳动物靶点 (mTOR) 和真核起始因子 (eIF) 2、eIF4 和 p70S6K。有趣的是，活体 mf 产生并分泌人类 FKBP1（亲环蛋白）的同源物，它是 mTOR 信号传导的负调节因子。 通过对从终生丝虫感染者和相对急性感染的外籍人士中纯化的细胞之间的基因表达进行详尽比较，研究了慢性感染本身对 T 细胞对丝虫感染反应的影响。使用基因表达谱，我们能够证明长期丝虫感染（基于离体整体基因表达）显示出基因表达显着下调的模式，最显着的是在 CD8+ 细胞中，但也在 CD4+ 细胞中/ 在一项研究中，我们利用来自库克群岛（班克罗夫氏菌流行）的特征明确的个体冷冻保存的细胞，我们利用多参数流来证明，慢性感染患者的中央记忆细胞（CD4+CCR7+CD127+CD27+CD45RA-）数量不仅减少，而且回复记忆细胞（CD3+）数量增加 CD45RA+CCR7-CD127+CD122+）表明慢性蠕虫感染（如慢性病毒感染）可能容易导致记忆细胞功能障碍。 由于慢性丝虫（和其他蠕虫）感染可能会改变对其他（非寄生虫）抗原的免疫反应性，并且这些改变可能对这些非丝虫感染的临床结果产生深远的影响，印度、马里和厄瓜多尔的合作研究表明，活动性丝虫感染和/或慢性肠道蠕虫感染的存在非常明显地削弱了 1 型（和 Th17）对丝虫感染的反应。 共同感染情况下的非丝虫抗原。 在过去的四年里，我们一直关注现有蠕虫感染对结核分枝杆菌 (Mtb)、疟疾和艾滋病毒的影响。 作为检查 Mtb 和丝虫感染之间相互作用的第一步，并根据丝虫/Mtb 双重感染的流行病学，建立了共感染的体外系统，并用于证明人类 DC 和巨噬细胞预先暴露于活丝虫寄生虫会诱导改变分枝杆菌进入和复制的免疫调节表型（Chatterjee， 未发表）。 同时，我们开发了一种体内模型，在该模型中，我们使小鼠产生微丝菌血症，然后用有毒的结核分枝杆菌（通过气溶胶）感染它们。我们的数据非常清楚地表明，微丝丝血症会诱导肺部巨噬细胞的替代激活，但无法改变结核分枝杆菌的生长或清除；来自这些小鼠肺部的微阵列数据表明干扰素-γ 和 IFN-γ 调节途径的普遍调节（Chatterjee，Talaat，未发表）。 离体人体研究更多地关注丝虫感染和未感染个体的潜伏性结核病，已经证明丝虫感染： 1) 调节 TLR 表达和功能以响应 Mtb 抗原 12； 2) 通过 CTLA-4 和 PD-1 的协同作用，显着改变 Mtb 特异性 Th1/Th17 反应，这对于维持潜伏期非常重要2； 3) 诱导调节潜伏 Mtb 感染患者的 Th17 反应的 Tregs 群体 13。我们现在通过开发多参数流式细胞术方法扩展了这些研究，以识别 Mtb 特异性干细胞记忆 (SCM) CD4+ 和 CD8+ T 细胞，并正在探索慢性丝虫抗原暴露与 Mtb 特异性记忆改变之间的关系 在马里的研究中，结合了疟疾和丝虫混合感染的临床和免疫学方面，我们以免疫学为重点的研究纵向（疟疾传播季节之前、期间和之后）探索了先前存在的丝虫感染对疟疾抗原反应的旁观者影响。 在相隔两年在不同地点进行的两项研究中，我们非常明确地表明，丝虫感染的存在可以调节对疟疾抗原的先天（TLR 介导的）反应。然而，更重要的是，我们已经表明，丝虫感染在丝虫/疟疾共同感染人群中以 IL-10 依赖性方式调节疟疾特异性 1 型细胞因子反应。 我们已经确定了在共丝虫/疟疾共同感染群体中调节疟疾特异性促炎细胞因子途径的细胞群，并且我们还证明丝虫感染几乎完全阻止了疟疾特异性多功能T细胞的诱导。 此外，我们还证明了 IRF-1 在调节疟疾特异性 Th1/Th17 反应中发挥的关键作用。