Mechanisms of action, optimization and application of Bregs

Bregs的作用机制、优化及应用

基本信息

批准号：
10585245
负责人：
JAMES FRANCIS MARKMANN
金额：
$ 63.77万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-01-01 至 2023-12-01
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10585245
关键词：
ARHGEF5 gene Adoptive Transfer Antibodies Antigen Presentation Antigen Targeting Antigens Area Autoimmunity B-Cell Activation B-Lymphocyte Subsets B-Lymphocytes Biological Assay Biological Markers Blood Bone Marrow Cell Communication Cell Therapy Cell Transplantation Cells Clinical Research Comparative Study Critical Pathways Data Development Endowment Engineering Environment Exhibits Experimental Models Flow Cytometry Funding Future Generations Goals Graft Rejection Graft Survival Hematologic Neoplasms Hypersensitivity IL2RA gene Immune response Immunosuppression In Vitro Innovative Therapy Interleukin-10 Investigation Islets of Langerhans Transplantation Kidney Transplantation Location Lymphocyte Malignant Neoplasms Medicine Messenger RNA Modeling Monitor Monoclonal Antibodies Mus Ovalbumin Pathway interactions Phenotype Population Process Property Refractory Regulatory T-Lymphocyte Rest Role Series Signal Induction Signal Pathway Signal Transduction Skin Skin Transplantation Specificity T cell response T-Cell Activation T-Cell Proliferation T-Lymphocyte TNF gene TNFRSF5 gene Technology Therapeutic Tissue Grafts Tissue Transplantation Tissues Toll-like receptors Transforming Growth Factor beta Translations Transplantation Transplantation Tolerance Vaccines Validation Work adaptive immune response adaptive immunity allograft rejection anti-CD20 arm chimeric antigen receptor chimeric antigen receptor T cells cytokine early phase clinical trial experimental study gene therapy humoral immunity deficiency immunoregulation in vivo innovation interest islet kidney allograft lipid nanoparticle liver allograft mRNA Expression novel organ transplant rejection pharmacologic premature prevent programmed cell death ligand 1 receptor response single-cell RNA sequencing standard of care stem cells transcriptomic profiling translational potential transplant model vaccine delivery vaccine development

项目摘要

PROJECT SUMMARY / ABSTRACT It has been suggested that the future of medicine rests in cell and gene therapy. While this assertion may be premature, it seems clear that these innovative therapies have extraordinary, paradigm shifting potential. For cell-based therapies, this is best exemplified by the powerful impact of chimeric antigen receptor (CAR) T cells in the treatment of hematological malignancies refractory to current standard of care (5). In the transplant realm, MSC’s, stem cell derived islets, and facilitator cells to promote bone marrow tolerance to renal grafts have shown encouraging results as cell-based therapeutics (6-8). In addition, numerous early phase clinical trials are underway exploring the potential of regulatory T cells (Tregs) to mitigate rejection of liver and kidney allografts (9, 10). More recently, CAR technology has been employed to generate CAR Tregs as more potent, off-the-shelf, donor antigen-specific regulatory populations (11). In the current proposal, we investigate the regulatory properties in the other arm of adaptive immunity to focus on the regulatory activities of B cells. After finding that B cells were required for tolerance in varied experimental transplant models and that B cells (or Bregs) isolated from mice tolerant to islets could adoptively transfer tolerance to otherwise untreated B cell deficient hosts, we sought to expand the tolerogenic Breg population ex vivo. In so doing, we made the unexpected observation that even naïve B cells stimulated ex vivo by Toll-like receptors (TLRs) manifested potent suppressive activity in MLRs and prevented graft rejection in vivo (12). With further study, we demonstrate that a variety of B cell activating signals induce Breg suppression and that, depending on the activating trigger, the mechanism of suppression in vivo varies. Our overarching hypothesis is that Breg suppression is executed through antigen presentation in the context of local immunoregulatory cytokine elaboration, such as TGF-ß and IL-10. Supporting this notion, we found that B cell specificity for the donor was essential to suppressive function, perhaps indicating cognate Breg-T cell/Treg communication (13, 14). Also noteworthy is our finding that clonal Breg populations with specificity for donor antigens exhibited the greatest suppressive potency in vitro and in vivo (13). Based on these findings, in Aim 3, we will conduct innovative studies to determine whether Bregs, imbued with donor specificity, through either transient or permanent expression of a donor-specific CAR, prevent allograft rejection. Furthermore, recent studies indicate that CAR can be delivered effectively in vivo using lipid nanoparticles (LNP) decorated with antibodies to target select cell populations, such as host B cells (15). The LNP approach developed for vaccine delivery also lends itself to parallel transfer and expression of mRNA payloads encoding suppressive molecules (IL-10, TGF-ß, etc.) to augment potency (16). Collectively, our proposed work will advance understanding of Breg mechanisms of differentiation and suppression, optimize Breg function and evaluate the potential of Bregs and CAR Bregs as cellular therapeutics.

项目概要/摘要有人认为医学的未来在于细胞和基因治疗，尽管这种说法可能还为时过早。很明显，这些创新疗法对于基于细胞的疗法具有非凡的、范式转变的潜力。嵌合抗原受体 (CAR) T 细胞在血液学治疗中的强大影响就是最好的例证。当前护理标准难治的恶性肿瘤 (5)。促进骨髓对肾移植物耐受的促进细胞已显示出令人鼓舞的结果此外，许多早期临床试验正在进行中，探索调节性 T 的潜力。细胞 (Treg) 来减轻肝脏和肾脏同种异体移植物的排斥反应 (9, 10) 最近，CAR 技术已得到应用。生成 CAR Tregs 作为更有效、现成的供体抗原特异性调节群体 (11)。在当前的提案中，我们研究了适应性免疫另一部分的监管特性，重点关注发现 B 细胞在各种实验性移植中具有耐受性所必需的。模型中，从对胰岛耐受的小鼠中分离出的 B 细胞（或 Bregs）可以过继地将耐受性转移到其他胰岛未处理的 B 细胞缺陷宿主，我们试图离体扩大耐受性 Breg 群体。出乎意料的观察结果是，即使是幼稚的 B 细胞在体外受到 Toll 样受体 (TLR) 刺激后也表现出有效的作用通过进一步研究，我们证明了多种 MLR 的抑制活性并可防止体内移植物排斥反应。 B 细胞激活信号会诱导 Breg 抑制，并且根据激活触发因素，Breg 抑制的机制我们的总体假设是 Breg 抑制是通过抗原呈递来执行的。在局部免疫调节细胞因子（例如 TGF-β 和 IL-10）的研究背景下，我们发现支持这一观点。 B 细胞对供体的特异性对于抑制功能至关重要，可能表明同源 Breg-T 细胞/Treg 同样值得注意的是我们发现克隆 Breg 群体对供体抗原具有特异性。在体外和体内表现出最大的抑制效力 (13) 基于这些发现，我们将在目标 3 中进行。创新研究，以确定充满捐助者特异性的 Bregs 是否通过暂时或永久的方式表达供体特异性 CAR 可以预防同种异体移植排斥。此外，最近的研究表明 CAR 可以被抑制。使用修饰有抗体的脂质纳米颗粒（LNP）有效地在体内递送以靶向选定的细胞群，例如宿主 B 细胞 (15) 为疫苗递送而开发的 LNP 方法也适用于并行转移和转移。表达编码抑制分子（IL-10、TGF-β 等）的 mRNA 有效负载以增强效力 (16)。我们提出的工作将推进 Breg 分化理解和抑制机制，优化 Breg 功能并评估 Bregs 和 CAR Bregs 作为细胞疗法的潜力。