Immune tolerance in the therapy of rheumatoid arthritis

描述（由申请人提供）：关于类风湿关节炎（RA）的免疫耐受诱导和维持的同步临床和机制研究的已发表数据很少。了解诱导耐受的机制至关重要，因为一旦目前使用的治疗方法控制了最初的症状性免疫激活，该方法可能有效地维持疾病控制。我们最近完成了一项由美国国立卫生研究院（nih）赞助的安慰剂对照II期试验，研究RA患者对dnaJP1的粘膜耐受性。dnaJP1是一种热休克蛋白衍生的肽，我们之前发现它是RA中T细胞介导的炎症的一个贡献者。dnaJP1治疗导致可检测的临床疗效，这与体外反应dnaJP1的T细胞产生促炎细胞因子TNFa的显著减少有关。产生假设的初步研究表明，表位特异性治疗影响T细胞谱系承诺，导致从促炎（TH-1和TH-17）到调节功能的变化。这在预先用羟氯喹（HCQ）治疗的患者中尤为明显。这些患者对dnaJP1治疗有较好的临床反应。HCQ预处理可以诱导一种新型的调节性T细胞（Treg），其存在是诱导耐受性所必需的。因此，本研究的假设是：i)表位特异性治疗对从TH-1/TH-17促炎T细胞（Teff）到Treg/耐受性细胞的梯度内T细胞谱系的相对代表性和功能有直接影响；ii) APC的变化是由HCQ治疗引起的，并且是一种新型调节性T细胞产生的前驱症状，这种T细胞通过PD-1的表达来识别；iii)治疗的效果最初是肽特异性的，随后影响先天和适应性免疫。目的是：i)证明治疗诱导具有调节功能的各种T细胞的出现：a)作为效应细胞的抑制因子，从而有利于免疫偏差；b)可以直接裂解同时在HLA上呈递dnaJP1的抗原呈递细胞（APC），并表达相应的配体（即表达PD-1配体结合PD-1 Treg）；ii)描述Teff从TH-1/TH-17到更耐受性表型的治疗诱导免疫偏差的性质和实体；iii)表征HCQ对耐受机制的“辅助”作用，特别关注HCQ诱导APC表型和功能的变化。特异性目标1：基于PD-1的共表达鉴定Treg亚群，表征其与dnaJP1免疫耐受的功能，并评估其对Teff和APC的抑制/调节活性。特异性目的2：表征Teff从促炎TH-1/TH-17到耐受性状态的免疫偏离的性质和机制。特异性目标3：研究治疗诱导的APC功能变化，特别关注HCQ在促进能够诱导和参与具有调节/抑制潜能的T细胞的膜表型表达中的“辅助”作用。我们的项目正在开发一种新的方法，直接解决对耐受性原的需求，作为目前使用的生物制剂的补充。这里提出的研究计划依赖于“从床边到实验台”的反向转化路线，是该项目的一个基本部分，因为它将从nih资助的II期试验中获得的独特样本收集中解剖和定义耐受性机制。这些研究有可能为人类免疫耐受的免疫学提供有价值的信息，也将有助于将基本的免疫学概念转化为设计更好的试验和预测治疗效果的新工具，以优化患者的护理方案。

DESCRIPTION (provided by applicant): There are few published data concerning the induction and maintenance of immune tolerance based on concurrent clinical and mechanistic studies in rheumatoid arthritis (RA). It is of critical importance to understand the mechanisms of the induction of tolerance because the approach may be effective in maintaining disease control once the initial, symptomatic immune activation has been controlled by currently used therapies. We have recently concluded a NIH-sponsored placebo-controlled pilot phase II trial of mucosal tolerization to dnaJP1 in RA. dnaJP1 is a heat shock protein-derived peptide we previously identified as a contributor of T cell-mediated inflammation in RA. dnaJP1 treatment led to detectable clinical efficacy, which correlated with a significant reduction in the production of pro-inflammatory cytokine TNFa by T cells in response to dnaJP1 in vitro. Hypothesis-generating preliminary studies suggest that epitope-specific therapy affects T cell lineage commitment, resulting in a change from a pro-inflammatory (TH-1 and TH-17) to regulatory function. This is particularly evident in patients pre-treated with hydroxychloroquine (HCQ). These patients had a better clinical response to the dnaJP1 treatment. Pre-treatment with HCQ may induce a novel type of regulatory T cells (Treg), whose presence is necessary for the induction of tolerance. Therefore the hypotheses for this study are: i) epitope-specific therapy has a direct effect on the relative representation and function of T cell lineages within the gradient comprised from TH-1/TH-17 pro-inflammatory effector T cells (Teff) to Treg/ tolerogenic cells; ii) changes in the APC are induced by treatment with HCQ and are prodromic to the generation of a novel type of regulatory T cells, which is identified by the expression of PD-1; iii) The effects of therapy are initially peptide-specific and subsequently affect both innate and adaptive immunity. The objectives are: i) To demonstrate that therapy induces the emergence of various types of T cells with regulatory function that: a) act as suppressors for effector cells, thus favoring an immune deviation; b) can directly lyse antigen presenting cells (APC) which at the same time present dnaJP1 on their HLA and express the appropriate ligands (i.e. express PD-1 ligands to bind PD-1 Treg); ii) To characterize the nature and entity of the therapy-induced immune deviation in Teff from TH-1/TH-17 to a more tolerogenic phenotype; iii) To characterize the "adjuvant" role that HCQ has on the mechanism of tolerization, with a specific focus on HCQ-induced changes in APC phenotype and function. Specific Aim 1: To identify sub-populations of Treg based on co-expression of PD-1, characterize their function in relationship to immune tolerization to dnaJP1, and evaluate their suppressor/regulatory activity on Teff as well as on APC. Specific Aim 2: To characterize the nature and mechanisms of the treatment-induced immune deviation of Teff from pro- inflammatory TH-1/TH-17 to a tolerogenic status. Specific Aim 3: To study treatment-induced changes in APC function, with a specific focus on the "adjuvant" role that HCQ may have in facilitating the expression of a membrane phenotype capable of inducing and engaging T cell with a regulatory/suppressor potential. Our program is developing a novel approach that directly addresses the need of a tolerogen as a complement to currently used biologics. The research plan proposed here relies on a "bedside back to bench" reverse translational itinerary and is a fundamental part of the project, as it will dissect and define the mechanisms of tolerance from a unique collection of samples already obtained from a NIH-funded Phase II trial. These studies have the potential to provide valuable information regarding the immunology of human immune tolerance and will also help translate basic immunology concepts into novel tools for designing better trials and predicting treatment efficacy to optimize a patient's care regimen.