Hyaluronic Acid Based Nanoparticles for Targeted Image-Guided Tumor Surgery

描述（由申请人提供）：该提案的总体目标是开发新型荧光造影剂，其可以在术中增强肿瘤，以指导手术肿瘤切除。该提案中使用的纳米颗粒将来自对透明质酸（HLA）的修饰。这些纳米颗粒具有捕获近红外（NIR）荧光染料的能力。在包埋时，这些NIR荧光染料被猝灭。此外，HLA是细胞表面受体CD 44的配体，并被透明质酸酶降解。理想地，透明质酸酶对基于HLA的纳米颗粒的特异性降解将释放再次发荧光的游离染料。透明质酸酶和CD 44在多种肿瘤中过表达，包括浸润性导管癌，这是在本提案中研究的。基于HLA的纳米颗粒将包括一类新的纳米颗粒生物传感器，可以特异性地识别患病细胞。一个关键的创新步骤是，这些近红外生物传感器可以很容易地检测到新的图像引导手术仪器，以提供实时图像引导肿瘤状态。实际上，已经设计了一种图像引导的手术系统，其用定向激发光束激发NIR荧光团。近红外发射光谱检测和CCD检测器在一个开销多摄像机检测器。NIR生物传感器和术中成像的结合解决了一个关键的公共卫生问题，即在第一次手术期间无法精确完成手术切除，这可能导致肿瘤复发率高。复发性肿瘤可降低患者预后，改变治疗方案，并且除了对医疗保健系统的额外手术的总体成本之外，还具有严重的心理后果。整合高度创新的技术，以改善接受肿瘤切除的患者的福利，有四个目标：（1）通过改变HLA分子量、引入交联化学和用聚乙烯包覆纳米颗粒来优化NIR染料的负载和NIR染料的胶体性质。（乙二醇），（2）确定荧光激活和CD 44靶向的机制，（3）进行体内肿瘤对比研究，包括图像引导手术功效，和（4）药物的总体安全性评价，包括详细的生物分布研究、体外炎症和免疫系统激活以及血液药代动力学。所有体内研究均在啮齿类动物中进行;荷人乳腺肿瘤异种移植物的小鼠、健康小鼠和大鼠。据推测，图像引导的肿瘤切除将减少复发性疾病，而纳米颗粒包埋染料将特异性增强肿瘤及其边缘，从而导致与对照相比更敏感的癌症检测。

DESCRIPTION (provided by applicant): The overarching goal of this proposal is to develop novel fluorescence contrast agents that can enhance tumors intraoperatively to guide surgical tumor removal. Nanoparticles used in this proposal will be derived from modifications to hyaluronic acid (HLA). These nanoparticles have the ability entrap near infrared (NIR) fluorescent dyes. Upon entrapment, these NIR fluorescent dyes are quenched. In addition, HLA is a ligand for the cell surface receptor CD44 and is degraded by hyaluronidases. Ideally, specific degradation of HLA-based nanoparticles by hyaluronidases will release free dye that is again fluorescent. Both hyaluronidases and CD44 are overexpressed in a variety of tumors, including invasive ductal carcinoma, which is investigated in this proposal. The HLA-based nanoparticles would comprise a new class of nanoparticle biosensors that specifically identify diseased cells. A key innovative step is that these NIR biosensors can be readily detected by new image-guided surgical instrumentation to provide real-time image-guidance on tumor status. Indeed, an image-guided surgery system has been designed that excites NIR fluorophores with a directed excitation beam. NIR emission is detected spectrally and by CCD detectors in an overhead multicamera detector. The combination of NIR biosensors and intraoperative imaging addresses a key public health concern, the inability to exact complete surgical removal during the first surgery, which can result in a high rate of recurrent tumors. Recurrent tumors, can decrease patient prognosis, change therapeutic regimens, and have severe psychological consequences in addition to the overall costs of additional surgery to health care system. The integration of highly innovative technology to improve patient welfare for those undergoing tumor removal is addressed in four aims: (1) optimize the loading of NIR dye and colloidal properties of NIR dyes through modifying HLA molecular weight, introducing crosslinking chemistry, and coating nanoparticles with poly(ethylene glycol), (2) determine the mechanism for fluorescence activation and CD44 targeting, (3) perform in vivo tumor contrast studies, including image-guided surgery efficacy, and (4) an overall safety evaluation of the agents that includes detailed biodistribution studies, inflammatory and immune system activation in vitro, and blood pharmacokinetics. All in vivo studies will be performed in rodents; mice bearing human breast tumor xenografts, healthy mice, and rats. It's hypothesized that image-guided tumor removal will decrease recurrent disease, while nanoparticle entrapped dye will specifically enhance tumors and their margins resulting in more sensitive cancer detection compared to controls.