Manipulating microenvironment and vasculature to enhance T cell infiltration into tumors

肿瘤中CD8 T细胞(TCD8)的存在是患者生存的一个积极的预后指标，但 TCD8在许多肿瘤中的表达很差。虽然这可能是肿瘤内不良的后果 除了扩散，也只有很小一部分过继转移的TCD8或CAR-T进入 肿瘤。我们已发表的初步数据表明，归巢受体配体(HRL)在肿瘤上的表达 血管系统是次优的，TCD8进入肿瘤可以通过解除免疫抑制而增强。 我们的工作还提出了一个正反馈模型，在该模型中，肿瘤内的效应器活动来自新进入的 TCD8是维持HRL表达和维持新出现的效应物进入所必需的。工作由以下人员进行 其他人则认为，促血管生成因子如血管内皮生长因子可能会以多种方式限制TCD8的渗透 机制，包括无序的血管结构，干扰内皮细胞的细胞因子信号 诱导HRL上调，抑制瘤内免疫。然而，这些不同的方面如何 TCD8效应分子是否直接进入肿瘤，对血管生成的影响还有待确定。还有还有 对先天免疫细胞和瘤内抗原在增加TCD8进入中的作用知之甚少 效应器。这个多PI R01应用程序是两个研究人员之间的合作，具有互补性 专业知识。恩格哈德实验室已经确定：基于归巢受体(HR)的TCD8效应器亚群 表达模式；HRL在肿瘤血管上的表达模式；以及介导的HR/HRL对 TCD8效应分子在肿瘤中的迁移。凯利实验室一直专注于开发工具和使用工程技术 研究血管内皮细胞在疾病中作用的方法。利用噬菌体展示技术，他们识别出 Hornerin，一种新的非血管内皮生长因子诱导蛋白，在肿瘤血管上过表达。霍纳林击倒领先 血管正常化和血流灌注增加，而不丢失血管。霍纳林可能是一个理想的选择 分子衰减，以促进血管正常化，而不产生混杂的多效性效应 在抑制血管内皮生长因子的情况下观察。这两位调查人员将使用这些新颖的工具和专业知识来理解 肿瘤内抗原、肿瘤血管和肿瘤如何调节TCD8直接进入肿瘤 微环境。目标1将确定肿瘤内免疫调节机制对HRL的影响 肿瘤血管和外源性TCD8效应分子运输的表达。目标2将确定 促血管生成因子和肿瘤血管归一化对肿瘤血管HRL表达的影响 外源性TCD8效应器贩运。目的3将确定先天免疫细胞和肿瘤内抗原在 促进TCD8效应分子向肿瘤转移。总体而言，这项工作将阐明限制迁移的因素 肿瘤特异性T细胞在接种疫苗或过继转移后进入肿瘤，并提出增强 它们的渗透和随后的治疗效果。此信息可与ACTIVE一起使用 疫苗接种或以过继转移为基础的免疫疗法，以在更广泛的范围内提高其效力 癌症患者。

The presence of CD8 T cells (TCD8) in tumors is a positive prognostic indicator of patient survival, but representation of TCD8 in many tumors is poor. While this could be a consequence of poor intratumoral proliferation, it is also the case that only a very small fraction of adoptively transferred TCD8 or CAR-T enter tumors. Our published and preliminary data indicates that homing receptor ligand (HRL) expression on tumor vasculature is suboptimal and that entry of TCD8 into tumors can be enhanced by relief of immunosuppression. Our work also suggests a positive feedback model in which intratumoral effector activity from newly entering TCD8 is needed to maintain HRL expression and sustain entry of newly arising effectors. Work conducted by others has suggested that pro-angiogenic factors such as VEGF may limit TCD8 infiltration by multiple mechanisms, including disorganized vascular structure, interference with cytokine signaling in endothelial cells to induce HRL upregulation, and suppression of intratumoral immunity. However, how these different aspects of angiogenesis influence direct TCD8 effector entry into tumors remains to be determined. There is also still little understanding of the roles that innate immune cells and intratumoral Ag play in augmenting entry of TCD8 effectors. This multi-PI R01 application is a collaboration between two investigators with complementary expertise. The Engelhard lab has identified: subpopulations of TCD8 effectors based on homing receptor (HR) expression pattern; the patterns of HRL expression on tumor vasculature; and the HR/HRL pairs that mediate TCD8 effector migration into tumors. The Kelly lab has focused on developing tools and using engineering approaches to study the role of the endothelium in disease. Using phage display technology, they identified hornerin, a novel non-VEGF induced protein overexpressed on tumor vasculature. Hornerin knockdown leads to vessel normalization and increased perfusion without loss of blood vessels. Hornerin may be an ideal molecule to attenuate in order to promote vessel normalization without the confounding pleiotropic effects observed when inhibiting VEGF. These two investigators will use these novel tools and expertise to understand how the direct entry of TCD8 into tumors is regulated by intratumoral Ag, tumor vasculature, and tumor microenvironment. Aim 1 will determine the impact of intratumoral immunoregulatory mechanisms on HRL expression on tumor vasculature and on exogenous TCD8 effector trafficking. Aim 2 will determine the impact of pro-angiogenic factors and tumor vessel normalization on HRL expression on tumor vasculature and on exogenous TCD8 effector trafficking. Aim 3 will determine the role of innate immune cells and intratumoral Ag in promoting TCD8 effector trafficking into tumors. Overall, this work will illuminate factors that limit the migration of tumor-specific T cells into tumors after vaccination or adoptive transfer, and suggest approaches to enhance their infiltration and subsequent therapeutic efficacy. This information may be used in conjunction with active vaccination or adoptive transfer-based immunotherapies to enhance their efficacy in a broader spectrum of cancer patients.