Topic 396 - Imaging for Cancer Immunotherapies-Moonshot

用荧光纳米金刚石（FND）标记的细胞的体内成像是在癌症免疫治疗期间监测免疫细胞的新方法。FND是无毒的，无限光稳定的纳米材料，很容易与抗体结合，并在近红外光谱区发射荧光。在这个I期SBIR中，我们将使用鼠黑色素瘤模型，并概述了一个计划，使用FND成像免疫抑制细胞群，因为它们在免疫治疗期间进入肿瘤微环境和外周组织。在目标1中，我们将50 nm FND与识别肿瘤相关巨噬细胞（TAM）、髓源性抑制细胞（MDSC）和调节性T细胞（T-reg）的抗体偶联。在目标2中，我们将制备TAM、MDSC和T-reg细胞，并使用商业荧光抗体通过流式细胞术对其进行表征。然后将使用TAM、MDSC和T-reg来验证我们的抗体-FND缀合物。在目标3中，我们将离体制备FND标记的TAM、MDSC和T-reg细胞，并在接受安慰剂或小鼠抗PD-L1抗体（程序性死亡配体1）抑制剂的荷黑色素瘤小鼠中荧光跟踪这些细胞群。我们还将进行平行研究，其中我们对通过尾静脉直接注射的抗体-FND缀合物进行成像。我们的研究结果将为预测免疫治疗的反应提供工具。

In vivo imaging of cells labeled with fluorescent nanodiamonds (FNDs) is a new way of monitoring immune cells during cancer immunotherapy. FNDs are non-toxic, infinitely photostable nanomaterials that are easily conjugated with antibodies, and emit fluorescence in the near infrared spectral region. In this Phase I SBIR, we will use a murine melanoma model and outline a plan to use FNDs for imaging immunosupressive cell populations as they enter the tumor microenvironment and peripheral tissues during immunotherapy. In Objective 1, we will conjugate 50 nm FNDs with antibodies that recognize tumor-associated macrophages (TAM), myeloid-derived suppressor cells (MDSC), and regulatory T cells (T-reg). In Objective 2, we will prepare TAM, MDSC and T-reg cells and characterize them by flow cytometry using commercial fluorescent antibodies. The TAM, MDSC and T-reg will then be used to validate our antibody-FND conjugates. In Objective 3, we will prepare FND-labeled TAM, MDSC and T-reg cells ex vivo and fluorescently track these cell populations in melanoma-bearing mice receiving placebo or mouse anti-PD-L1 antibody (programmed death ligand 1) inhibitor. We will also perform parallel studies where we image antibody-FND conjugates that are directly injected through the tail-vein. Our results will provide tools for predicting the response to immunotherapy.