Lymphatic delivery of immunotherapy to prevent irAEs

随着高等脊椎动物从海洋进化为陆地居民，以及陆地抗原(Ag)暴露的增加， 适应性免疫系统从一个集中的系统演变成一个依赖于区域排水的系统。 淋巴结节(DLN)，允许对多个AGs的免疫反应，同时保持中枢耐受。尽管 LNS启动免疫反应对系统免疫/耐受、检查点阻断的重要性 免疫疗法(CBI)是通过静脉给药的，通常无法到达作为DLN的部位 功能失调的T细胞启动与肿瘤耐受性有关(TAG)。当系统地给药时， 这些疗法以一种不分青红皂白和全系统的方式起作用，往往违反自我容忍和领先 严重免疫相关不良事件(IrAEs)。 我们假设，在不同的淋巴分水岭内对DLN进行区域性免疫治疗将 (一)增强系统免疫力或耐受性；及(二)与系统免疫系统相比，大大减少免疫不良反应 送货。我们假设的科学依据来自我们在临床前、原位乳房(4T1)和黑色素瘤(B16F10)癌症转移研究中的数据。我们表明，αCTLA-4单独或通过淋巴传递 与α结合使用时，PD-1(I)可改善抗肿瘤反应，(Ii)可产生与 全身或静脉注射。给药，和/或(Iii)改善这些非免疫原性肿瘤的远处转移 模特们。利用微针阵列设备和近红外荧光进行临床前和临床研究 淋巴成像显示了将药物专门输送到区域淋巴结的技术能力。然而， 还没有临床前的证据表明淋巴输送将缓解irAEs，因为缺乏一种 易感小鼠模型。在进一步研究淋巴输送或转化为癌症之前 对于患者，需要证明减少irAEs的好处。由于irAEs限制了αCTLA-4/αPD-1的联合治疗，而毒性更大的激动剂α4-1BB CBIS，淋巴输送可以提供实质性的 需要取得突破，扩大CBIS的使用，以治疗更多处于疾病早期的癌症患者。 在NCI临床和转化性探索/发育R21(PAR-20-292)项目中，我们建议使用 Foxp3-DTR小鼠短暂性Treg耗竭模型的建立 静脉注射。和淋巴输送的CBIS。我们的具体目标是(1)描述免疫后果 由静脉注射产生。αCTLA-4/αPD-1和α4-1BB在非荷瘤C57BL/6和C57BL/6中的淋巴传递 BALB/C株Foxp3-DTR小鼠与TO(2)抗肿瘤免疫和免疫读数的比较 静脉注射的后果。4T1和B16F10荷瘤动物的CBIS淋巴传递。 在实践中，临床观察的irAEs被认为是CBI反应的早期指标。如果成功，我们将 将使irAEs与抗肿瘤免疫脱钩，并通过改变我们提供的方式来改进癌症治疗 免疫调节疗法。

As higher vertebrates evolved from the sea into land dwellers and terrestrial antigen (Ag) exposure increased, the adaptive immune system evolved from a centralized system to one dependent upon regional draining lymph nodes (dLNs) that allow immune responses to multiple Ags while preserving central tolerance. Despite the importance of LNs initiating immune responses for systemic immunity/tolerance, checkpoint blockade immunotherapies (CBIs) are administered intravenously, often failing to reach the dLNs that are the sites of dysfunctional T cell priming responsible for tolerance to tumor Ags (tAgs). When administered systemically, these therapies act in an Ag-indiscriminate and system-wide fashion often breaching self-tolerance and leading to severe immune related adverse events (irAEs). We hypothesize that regional delivery of immunotherapies within the distinct lymphatic watersheds to dLNs will (i) enhance systemic immunity or tolerance and (ii) substantially reduce irAEs when compared to systemic delivery. Scientific justification for our hypothesis comes from our data in preclinical, orthotopic breast (4T1) and melanoma (B16F10) studies of cancer metastases. We show that lymphatic delivery of αCTLA-4 alone or in combination with αPD-1 (i) improves anti-tumor responses, (ii) results in complete responses not seen with systemic or i.v. administration, and/or (iii) ameliorates distant metastases in these otherwise non-immunogenic models. Preclinical and clinical studies using microneedle array devices and near-infrared fluorescence lymphatic imaging shows the technical ability to deliver drug specifically to regional lymph nodes. However, there has been no preclinical demonstration that lymphatic delivery will alleviate irAEs, due to the lack of a susceptible mouse model. Before further study of lymphatic delivery can be made or translated into cancer patients, the benefit of reduced irAEs needs to be demonstrated. Because irAEs limit combinational αCTLA-4/αPD-1 therapy and the more toxic, agonist α4-1BB CBIs, lymphatic delivery could provide a substantial breakthrough needed expand the use of CBIs to treat more cancer patients at earlier stages of disease. In this NCI Clinical and Translational Exploratory/Developmental R21 (PAR-20-292) project, we propose to use a well-characterized Foxp3-DTR mouse model of transient Treg depletion to provide a readout of irAEs from i.v. and lymphatically delivered CBIs. Our specific aims are to (1) characterize immunological consequences resulting from i.v. and lymphatic delivery of αCTLA-4/αPD-1 and α4-1BB in non-tumor bearing, C57BL/6 and Balb/C strains of Foxp3-DTR mice and to (2) compare anti-tumor immunity and readouts of immunological consequences from i.v. and lymphatic delivery of CBIs in 4T1 and B16F10 tumor bearing animals. In practice, clinical observations of irAEs are associated as early indication of CBI response. If successful, we will decouple irAEs from anti-tumor immunity and improve cancer treatments by changing the way we deliver immune modifying therapeutics.