Identification of the immunomodulatory mechanisms of nanocarrier-enhanced costimulation blockade in an allogeneic portal vein islet transplantation model

异体门静脉胰岛移植模型中纳米载体增强共刺激阻断的免疫调节机制的鉴定

• 批准号: 10494100
• 负责人: Evan A. Scott
• 金额: $ 18.98万
• 依托单位: NORTHWESTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-24 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10494100
• 关键词: Address; Adolescent; Allogenic; American; Amputation; Anti-Inflammatory Agents; Antigen-Presenting Cells; Antigens; Benchmarking; Biodistribution; Biological; Biological Assay; Blindness; Blood Glucose; CD8-Positive T-Lymphocytes; CD80 gene; CD8B1 gene; CTLA4 gene; CTLA4-Ig; Cell Cycle; Cells; Cessation of life; Chimeric Proteins; Clinical; Collaborations; Data; Disease; Drug Carriers; Encapsulated; Endocrine System Diseases; Engineering; Erythrocytes; Flow Cytometry; G1 Phase; Graft Survival; Heart; Histocompatibility Antigens; Hydrophobicity; Hypoglycemia; Immune; Immunoglobulins; Immunologics; Immunosuppression; Immunosuppressive Agents; Immunotherapy; Inflammatory; Injury; Insulin; Insulin-Dependent Diabetes Mellitus; Interleukin-2; Intestines; Islets of Langerhans Transplantation; Kidney; Kidney Failure; Liver; Major Histocompatibility Complex; Mediating; Methods; Mixed Lymphocyte Culture Test; Neuropathy; Patients; Peripheral Blood Lymphocyte; Polymers; Population; Portal vein structure; Production; Protocols documentation; Regimen; Regulation; Regulatory T-Lymphocyte; Rodent Model; Self Administration; Sirolimus; Specificity; Splenocyte; Structure of beta Cell of islet; Sulfides; T-Cell Proliferation; T-Lymphocyte; TNFRSF5 gene; Testis; Therapeutic; Therapeutic immunosuppression; Toxic effect; Transplantation; Up-Regulation; Work; alternative treatment; anti-CTLA4; base; clinically relevant; cost; drug efficacy; ethylene glycol; experience; immunoregulation; improved; in vivo; islet; liver transplantation; mTOR Inhibitor; mTOR inhibition; monocyte; mouse model; nanocarrier; nanomaterials; nanoscale; novel; post-transplant; prevent; propylene; side effect; standard of care; subcutaneous; transplant model; uptake

PROJECT SUMMARY Dysregulation of blood glucose due to T1D leads to both short term consequences such as hypoglycemia induced injury and death, and long-term complications including amputation, blindness, kidney failure, and neuropathy. Islet transplantation has the potential to provide biologic glycemic regulation for all T1D patients, effectively curing the disease. However, this promising therapy is plagued by the requirement for ineffective immunosuppressive therapies. Currently, only 50 to 70% of grafts remain viable at 5 years post-transplantation, largely due to the immunosuppressive therapy causing toxicity and failing to fully protect the graft. Currently, a costly cocktail of immunosuppressive drugs is given in a rarely successful attempt to provide broad immune coverage with side effect mitigation. Thus, a need exists for simpler, lower cost, and more effective alternatives to these immunosuppressive regimens that can maintain islet transplant survival without off-target side-effects. The objective of this proposal is to mechanistically understand how repurposing a single component of these immunosuppressive cocktails, rapamycin, using engineered nanoscale drug carriers can provide sustained islet protection. Vesicular polymeric nanocarriers (i.e. polymersomes, PS) encapsulating rapamycin (rPS) were found to uniquely change the cellular biodistribution of rapamycin to avoid side-effects and significantly improve efficacy. Importantly, rapamycin normally has a wide cellular biodistribution and functions by directly inhibiting T cell proliferation, but rPS completely avoids T cells and instead switches the immunosuppressive mechanism to a selective and potent costimulation blockade of antigen presenting cells (APCs). This novel cell-selective nanocarrier-enhanced costimulation blockade was characterized by an upregulation of CD8+ regulatory T cells and double positive CD4+CD8+ T cells, achieving sustained normoglycemia in a rigorous fully major histocompatibility complex (MHC) mismatched allogenic intraportal (liver) islet transplantation mouse model. Here, this proposal will investigate and benchmark the immunological mechanism of rPS against the clinically relevant therapeutic belatacept, a CTLA4-IgG fusion protein that induces costimulation blockade via an alternative method: the blocking of CD80/86 coreceptors on APCs. The following aims will be achieved: Aim 1: Determine whether rPS induces general immunosuppression or antigen-specific tolerance. It is currently not known whether rPS induce antigen-specific or general systemic immunosuppression. A novel ex vivo mixed lymphocyte reaction assay and in vivo dual antigen-specific / non-specific islet transplantation will address this question. Aim 2: Compare the immunomodulatory mechanisms of costimulation blockade induced by rPS vs. CTLA4-IgG for enhanced allogenic islet graft survival. High parameter flow cytometry using T-distributed Stochastic Neighbor Embedding (tSNE) analysis and assessment of long-term graft survival following fully-MHC mismatch islet transplantation will be performed.

项目概要 T1D 引起的血糖失调会导致低血糖等短期后果 诱发损伤和死亡，以及长期并发症，包括截肢、失明、肾衰竭和 神经病。胰岛移植有潜力为所有 T1D 患者提供生物血糖调节， 有效治愈疾病。然而，这种有希望的疗法受到无效治疗的困扰。 免疫抑制疗法。目前，只有 50% 至 70% 的移植物在移植后 5 年后仍然存活， 主要是由于免疫抑制治疗引起毒性并且未能充分保护移植物。目前，一个 昂贵的免疫抑制药物混合物在提供广泛免疫的尝试中很少成功 覆盖并减轻副作用。因此，需要更简单、成本更低且更有效的替代方案 这些免疫抑制方案可以维持胰岛移植存活而不会产生脱靶副作用。 该提案的目标是机械地理解如何重新利用这些的单个组件 免疫抑制鸡尾酒，雷帕霉素，使用工程纳米级药物载体可以提供持续的胰岛 保护。发现了封装雷帕霉素（rPS）的囊泡聚合物纳米载体（即聚合物囊泡，PS） 独特地改变雷帕霉素的细胞生物分布，以避免副作用并显着改善 功效。重要的是，雷帕霉素通常具有广泛的细胞生物分布，并通过直接抑制 T细胞增殖，但rPS完全避开T细胞，而是切换免疫抑制机制 对抗原呈递细胞（APC）进行选择性和有效的共刺激阻断。这种新颖的细胞选择性 纳米载体增强的共刺激阻断的特点是 CD8+ 调节性 T 细胞上调 和双阳性 CD4+CD8+ T 细胞，在严格的完全专业中实现持续正常血糖 组织相容性复合体（MHC）不匹配的同种异体门静脉内（肝）胰岛移植小鼠模型。 在此，本提案将研究 rPS 的免疫学机制并与临床研究进行比较。 相关治疗贝拉西普，一种 CTLA4-IgG 融合蛋白，可通过 替代方法：阻断 APC 上的 CD80/86 辅助受体。将实现以下目标： 目标 1：确定 rPS 是否会诱导一般免疫抑制或抗原特异性耐受。目前是 尚不清楚 rPS 是否会诱导抗原特异性或全身性免疫抑制。一种新颖的离体混合 淋巴细胞反应测定和体内双抗原特异性/非特异性胰岛移植将解决这个问题 问题。 目标 2：比较 rPS 与 CTLA4-IgG 诱导的共刺激阻断的免疫调节机制 提高同种异体胰岛移植物的存活率。使用 T 分布随机邻域的高参数流式细胞术 完全 MHC 错配胰岛后长期移植物存活的嵌入 (tSNE) 分析和评估 将进行移植。