TREATMENT OF AUTOIMMUNITY WITH REGULATORY T LYMPHOCYTES

描述（由申请人提供）：促炎性Th1和Th17 t淋巴细胞协调许多器官特异性自身免疫性疾病，如多发性硬化症（MS）和I型糖尿病。这些细胞的病理活性可由不同形式的调节性T淋巴细胞（Treg）调节，其中最显著的是表达Foxp3转录因子的Treg。因此，Foxp3+ Treg的过继免疫疗法在自身免疫性疾病的选择性治疗中具有前景。我们的实验室特别专注于Foxp3+ Treg的治疗应用，Foxp3+ Treg是由TGF-2调节幼稚T淋巴细胞产生的。我们证明了这些“诱导Treg”（iTreg）的细胞特性不同于直接分离的内源性Treg（天然Treg， nTreg）。尽管如此，iTreg和nTreg在治疗一种模型自身免疫性疾病，实验性过敏性脑脊髓炎（EAE）方面同样有效，并且通过相似的机制起作用。在本论文中，我们将阐述iTreg的独特生物学特性，并为其临床转化为细胞免疫治疗药物奠定基础。在初步研究中，我们证明了在过继性转移后，大部分的iTreg，而不是nTreg，失去了Foxp3的表达。iTreg和nTreg之间的一个关键区别在于它们的自我特异性程度。自我特异性会影响t细胞的稳态，我们假设也会影响t细胞的存活和功能。在Aim 1中，我们将研究TCR特异性在iTreg存活、Foxp3保存和治疗活性中的作用。我们的初步数据表明，iTreg和nTreg一样，都是高效的，以il -10依赖的方式预防和治疗EAE，并催化额外的自身抗原特异性Treg（感染耐受）的发展。在Aim 2中，我们将确定iTreg如何通过将病理性免疫反应转变为调节性反应来诱导免疫耐受，以及IL-10在其中的具体作用。我们进一步证明，TLR配体显著提高了治疗转移iTreg中Foxp3表达的保存和存活。我们假设通过APC或直接进入iTreg的TLR激活可促进iTreg的存活和活性。在Aim 3中，我们将确定先天免疫途径如何改变iTreg的治疗活性，并探讨TLR激动剂在iTreg诱导和免疫治疗中的可能辅助作用。这些研究将提供新的见解，了解iTreg如何在治疗转移后调节免疫，以及它们如何在功能上优化到最大的效力和疗效，并将促进iTreg免疫治疗的临床转化。公共卫生相关性：当免疫系统不能识别个体自身的细胞和组织并攻击它们时，疾病就会发展。效应t淋巴细胞是免疫系统中的一类细胞，在协调自身免疫反应和介导组织损伤中起关键作用。该提案的目标是利用一种不同类型的T淋巴细胞，即能够特异性抑制效应T淋巴细胞功能的调节性T淋巴细胞，促进自身免疫性疾病的新细胞疗法的发展。

DESCRIPTION (provided by applicant): Pro-inflammatory Th1 and Th17 T-lymphocytes orchestrate many organ-specific autoimmune diseases, such as multiple sclerosis (MS) and type I diabetes. The pathologic activity of these cells can be modulated by different forms of regulatory T lymphocytes (Treg), most prominently Treg expressing the Foxp3 transcription factor. Adoptive immunotherapy with Foxp3+ Treg therefore holds promise in the selective treatment of autoimmune conditions. Our laboratory has specifically focused on the therapeutic application of Foxp3+ Treg that are generated by conditioning naove T lymphocytes with TGF-2. We demonstrated that the cellular properties of these "induced Treg" (iTreg) differ from those of directly isolated endogenous Treg (natural Treg, nTreg). Despite this, iTreg and nTreg are equivalently potent in treating a model autoimmune disease, experimental allergic encephalomyelitis (EAE), and operate through similar mechanisms. In this proposal, we will address the unique biology of iTreg, and lay a foundation for their clinical translation into a cellular immunotherapeutic. In preliminary studies we demonstrated that a large proportion of iTreg, but not nTreg, lose Foxp3 expression after adoptive transfer. One key difference between iTreg and nTreg is in their extent of self-specificity. Self-specificity will impact T-cell homeostasis, and we hypothesize will also influence iTreg survival and function. In Aim 1, we will study the role of TCR specificity in iTreg survival, Foxp3 preservation, and therapeutic activity. Our preliminary data shows that iTreg, like nTreg, are highly potent, operate to prevent and treat EAE in an IL-10-dependent manner, and catalyze the development of additional autoantigen-specific Treg (infectious tolerance). In Aim 2, we will determine how iTreg induce immune tolerance by diverting a pathologic immune response into a regulatory response, and the specific role of IL-10 in this. We have further demonstrated that TLR ligands dramatically enhance the preservation of Foxp3 expression in and survival of therapeutically transferred iTreg. We hypothesize that TLR activation, either through APC or directly into iTreg, promotes the survival and activity of iTreg. In Aim 3, we will identify how innate immune pathways alter iTreg therapeutic activity, and probe a possible adjunct role for TLR agonists in iTreg induction and immunotherapy. These studies will provide new insights into how iTreg modulate immunity after therapeutic transfer and how they may be functionally optimized to maximum potency and efficacy, and will facilitate the clinical translation of iTreg immunotherapy PUBLIC HEALTH RELEVANCE: diseases develop when the immune system fails to recognize an individual's own cells and tissues as self, and attacks them. Effector T-lymphocytes, a class of cells within the immune system, are critically involved in orchestrating autoimmune responses and mediating tissue damage. This proposal's goal is to promote the development of new cellular therapies for autoimmune diseases using a different class of T lymphocytes, called regulatory T lymphocytes that are able to specifically suppress effector T lymphocyte functions.