Developing Multimodal Multiplexed ImmunoPET-Raman Probes to Guide Immunotherapies

项目摘要/摘要： PD-1/PD-L1轴的抑制剂已经成功地用于多种疾病。然而，只有很小的子集 的患者对这些方案有反应，并确定可能从这些疗法中受益的患者仍然存在 很有挑战性。目前的临床标准依赖于未能准确预测PD-L1的组织病理学，因为 患者之间的空间和时间异质性。此外，仅对患者进行PD-L1筛查并不是 由于实验室间PD-L1检测的显著差异而预测治疗反应的必要性 同时检测多个免疫标记物。这建立了我们的科学前提，即一个紧急的 需要能够检测PD-L1和其他标志物的准确的非侵入性诊断工具 在体内直接参与免疫调节。而免疫PET(正电子发射断层扫描)成像 改变了我们在体内检测单一免疫标记物的能力，PET无法实现多路传输 因为放射性核素之间的信号无法区分。如果没有多路传输的能力，患者将 接受多次放射性示踪剂剂量和重复辐射暴露。此外，动态变化在 治疗期间的免疫标记物将被遗漏，因为顺序剂量不同的放射性示踪剂将需要 &gt；两次剂量之间的等待时间为1周，以允许放射性示踪剂的衰变。我们的目标是解决 目前方法的局限性，并使体内PD-L1和CD8+T细胞的多重检测成为可能 一种创新的纳米探针，免疫活性金纳米颗粒(IGNS)。拉曼抗体标记免疫球蛋白 记者，和89Zr放射性示踪剂协同结合了免疫PET和表面增强的优点 拉曼光谱(SERS)。SERS是一种光学技术，它利用近红外光来增强分子的振动 拉曼报告器的信号，可实现适用于多路复用的窄光谱特征。我们的方法是 独一无二，因为临床可翻译的免疫球蛋白无缝结合了深度分辨的全身成像 PET具有表面增强拉曼散射的高分辨率和多路复用能力，能够同时检测两者 体内免疫标记物具有高度的特异性。在体内检测这两种免疫标记物很重要，因为 PD-L1和CD8在治疗过程中和治疗后都发生了动态变化，而这些变化不是静态的 测量受体或通过单一生物标志物成像。而免疫标记物的检测与免疫球蛋白相关 对于许多疾病，我们将使用乳腺癌(BC)的小鼠模型，因为PD-L1和CD8是免疫标记物 在BC治疗反应中起关键作用。免疫球蛋白将在原位BC小鼠体内同时检测PD-L1和CD8 模型(目标1)，监测对免疫疗法的反应(目标2)，并在临床相关的人性化中进行验证 小鼠(目标3)。IGNS是一个可推广的平台，最终我们的策略可以映射到其他疾病上 包括感染和自身免疫，其中PD-L1和CD8生物标记物也发挥关键作用。此外，igns 也可以通过抗体靶向许多其他生物标记物，促进多发性硬化的治疗反应 目前的临床病理方法无法达到前所未有的精确度。

Project Summary/Abstract: Inhibitors of the PD-1/PD-L1 axis has been successful across multiple diseases. However, only a small subset of patients respond to these regimen and identifying patients likely to benefit from these therapies remains challenging. Current clinical standard relies on histopathology that fail to accurately predict PD-L1 due to spatial and temporal heterogeneities among patients. Further, screening patients for PD-L1 alone is not predictive of treatment response due to significant variabilities in PD-L1 assays across labs necessitating simultaneous detection of multiple immunomarkers. This establishes our scientific premise that an urgent need exists for accurate noninvasive diagnostic tools that enables detection of both PD-L1 and other markers involved in immune modulation directly in vivo. Whereas ImmunoPET (positron emission tomography) imaging has transformed our ability to detect single immunomarkers in vivo, multiplexing cannot be achieved with PET as signal between radionuclides cannot be distinguished. Without the ability to multiplex, patients would undergo multiple radiotracer dosing and repeated radiation exposure. Further, dynamic changes in immunomarkers during treatment would be missed as sequential dosing of different radiotracers would require >1 week wait time between doses to allow for decay of the radiotracers. Our objective is to address the limitations of current approaches and enable multiplexed detection of both PD-L1 and CD8+ T cells in vivo with an innovative nanoprobe, immunoactive gold nanoparticles (IGNs). IGNs labeled with antibodies, Raman reporters, and 89Zr radiotracers synergistically integrates the merits of immunoPET with surface-enhanced Raman spectroscopy (SERS). SERS, an optical technique, uses near-infrared light to enhance the vibrational signal of Raman reporters enabling narrow spectral features amenable for multiplexing. Our approach is unique because clinically-translatable IGNs seamlessly combine the depth-resolved whole body imaging of PET with the high resolution and multiplexing ability of SERS enabling simultaneous detection of both immunomarkers in vivo with high specificity. Detection of both immunomarkers in vivo is important because dynamic changes occur in both PD-L1 and CD8 during and after treatment that are not captured by static measure of receptors or by single biomarker imaging. Whereas immunomarker detection with IGNs is relevant to many diseases, we will use mouse models of breast cancer (BC) since PD-L1 and CD8 immunomarkers play a critical role in BC treatment response. IGNs will detect both PD-L1 and CD8 in orthotopic BC mouse models (Aim 1), monitor response to immunotherapies (Aim 2), and validate in clinically-relevant humanized mice (Aim 3). IGNs is a generalizable platform and ultimately our strategy can be mapped onto other diseases including infection and autoimmunity where PD-L1 and CD8 biomarkers also play a key role. Further, IGNs can also be targeted to a number of other biomarkers via antibodies facilitating treatment response in multiple disorders with unprecedented accuracy not achievable with current clinicopathological approaches.