Quantum Dots for NIR Fluorescence Imaging of Tumor Angiogenesis

用于肿瘤血管生成的近红外荧光成像的量子点

• 批准号: 7280020
• 负责人: XIAOYUAN CHEN
• 金额: $ 16.6万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-13 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7280020
• 关键词: Acute; Affinity; Animals; Antibodies; Apoptosis; Atherosclerosis; Binding; Biocompatible; Biocompatible Coated Materials; Biodistribution; Biological; Biological Assay; Bone Marrow; Cadmium; Cell Adhesion; Cell Adhesion Molecules; Cell Communication; Cell surface; Cells; Cellular biology; Chemicals; Chemistry; Chronic; Class; Classification; Clinic; Clinical; Compatible; DNA; Detection; Development; Diabetic Retinopathy; Disease; Drug Kinetics; Electronics; Endothelial Cells; Epithelium; Evaluation; Extracellular Matrix; Family; Fluorescence; Fluorescent Dyes; Goals; Heavy Metals; Hematology; Histology; Human; Image; Imagery; Immunofluorescence Immunologic; In Vitro; Integrin Binding; Integrins; Kidney; Kinetics; Label; Libraries; Ligands; Liver; Magnetic Resonance Imaging; Malignant Neoplasms; Medical; Methods; Modification; Molecular; Molecular Probes; Multimodal Imaging; Nanoconjugate; Neoplasm Metastasis; Object Attachment; Oligonucleotides; Operative Surgical Procedures; Optics; Particle Size; Pathway interactions; Peptide antibodies; Peptides; Performance; Permeability; Play; Positron-Emission Tomography; Preparation; Process; Property; Protein Overexpression; Proteins; Quantum Dots; RGD (sequence); Radioisotopes; Radiolabeled; Range; Rheumatoid Arthritis; Role; Science; Screening procedure; Semiconductors; Series; Serum; Solid Neoplasm; Spleen; Structure; Techniques; Technology; Testing; Therapeutic procedure; Time; Tissues; Toxic effect; Translating; Translations; Tumor Angiogenesis; Tumor-Associated Vasculature; Ultrasonography; Vascular Endothelial Growth Factors; Vascular remodeling; Water; Xenograft Model; adhesion receptor; analog; angiogenesis; base; cytotoxicity; extracellular; fluorescence imaging; imaging probe; in vivo; innovation; member; molecular imaging; monolayer; nanocrystal; nanoparticle; neoplastic; neoplastic cell; next generation; particle; peptidomimetics; radiotracer; receptor; restenosis; single photon emission computed tomography; success; surface coating; tumor; uptake

DESCRIPTION (provided by applicant): Our long-term objective is to develop appropriate probes for multimodality molecular imaging of tumor angiogenesis and metastasis. Intermediate objective of this application is to develop cyclic RGD peptide conjugated quantum dots (QDs) for near-infrared (NIR) fluorescence imaging of av¿3 integrin expression in vivo. Cell adhesion molecule av¿3 integrin plays a key role in angiogenesis related diseases including cancer, atherosclerosis, rheumatoid arthritis, restenosis and diabetic retinopathy. Inhibition of av¿3 integrin activity by mAbs, cyclic RGD peptide antagonists, and peptidomimetics has been shown to induce endothelial apoptosis, to inhibit angiogenesis, and to increase endothelial monolayer permeability. Suitably labeled RGD peptides and antibodies have also been developed by us and others for MRI, ultrasound, NIR fluorescence, and radionuclide (PET and SPECT) imaging of integrin expression in vivo. Recently we demonstrated for the first time that RGD peptide conjugated QDs are able to target the extracellular segment of integrin av¿3 in an xenograft model. However, the enthusiasm for further studies of these nanoconjugates is mitigated by the unfavorable in vivo kinetics and cadmium-based cytotoxicity of the traditional quantum dots. We propose here to develop the next generation of biocompatible QDs for NIR fluorescence imaging. These particles are ultra small with thin coating material and are not made of cadmium chalcogenide materials. This type of QDs are suitable for animal imaging studies and eventually human use. First, we will develop a small library of non-Cd based QDs and conjugate the new QDs with RGD peptide. The performance of the newly developed non-Cd QDs will be compared with traditional Cd-based QDs. Efforts will also be spent to reduce non-specific binding. Second, we will evaluate the integrin targeting efficacy of QD-RGD in vivo. We will also directly compare biologically modified QDs with traditional molecular imaging probes by labeling RGD peptide with fluorescent dyes. In order to fully characterize the biodistribution and pharmacokinetics of the QD-RGD conjugates, we will radiolabel the newly developed QD-RGD conjugates with Cu (t1/2 = 12.7 h) and 64 124 I (t1/2 = 4.2 d) for combined NIR fluorescence and PET imaging. Finally, both Cd and non-Cd based QD-RGD conjugates will be subjected to acute and chronic toxicity studies. We expect that the newly developed non-Cd QDs with little or no toxicity will be amenable for clinical translation. The success of this study with RGD peptide modification for integrin av¿3 can be extended to QD multiplexing to provide the real-time information about cell surface markers (indicating malignancy, tumor type, and potentially influencing therapeutic procedure). Such information will be crucial for fluorescence-guided surgery by sensitive, specific, and real-time intraoperative visualization of molecular features of normal and diseased processes. Fluorescent semiconductor nanocrystals (a.k.a. quantum dots) have evolved over the last two decades from pure electronic materials science to biological applications. Various coating techniques have been applied to make QDs biocompatible (water-soluble and biologically stable). Suitably conjugated QDs (through antibody, proteins, peptides or oligonucleotides) are most commonly used in cell biology applications, including DNA array technology, immunofluorescence assays. However, preparation of QDs for molecular imaging has, so far, been severely under-developed. In addition, cadmium based cytotoxicity further hampered the development of such nanoconstructs for in vivo applications. In this application we thrive to develop non- cadmium based ultra small QDs for tumor angiogenesis imaging. We will develop and characterize a library of QD-RGD conjugates, followed by in vitro and in vivo screening. The QDs with suitable imaging quality will be subjected to acute and chronic toxicity studies. The success of this approach will allow clinical translation of QD based probe for fluorescence imaging.

描述（由应用提供）：我们的长期目标是为肿瘤血管生成和转移的多模式分子成像开发适当的问题。该应用的中间目的是开发循环RGD肽共轭量子点（QD），以用于近红外（NIR）荧光成像3的av¿3整合素表达体内的近红外（NIR）荧光成像。细胞粘附分子AV¿3整联蛋白在血管生成相关疾病中起关键作用，包括癌症，动脉粥样硬化，类风湿关节炎，再狭窄和糖尿病性视网膜病。已证明通过单克隆抗体，环状RGD辣椒和肽仪抑制AV¿3整联蛋白活性可诱导内皮细胞凋亡，抑制血管生成并增加内皮单层通透性。我们和其他人也开发了适当标记的RGD Pepperides和抗体，用于MRI，超声，NIR荧光和放射性荧光（PET和SPECT）成像的体内表达成像。最近，我们首次证明了RGD Peppered QD能够在异种移植模型中靶向整联蛋白AV¿3的细胞外段。但是，传统量子点的体内动力学和基于镉的细胞毒性不利，可以减轻对这些纳米偶联物的进一步研究的热情。我们在这里建议开发下一代的生物相容性QD，以用于NIR荧光成像。这些颗粒是非常小的，具有薄涂层材料，不是由镉辣椒素材料制成的。这种类型的QD适用于动物成像研究，最终适用于人类使用。首先，我们将开发一个基于非CD的QD的小库，并将新QD与RGD Pepper结合在一起。新开发的非CD QD的性能将与传统的基于CD的QD进行比较。还将花费努力来减少非特异性结合。其次，我们将评估体内QD-RGD的整联蛋白靶向效率。我们还将通过将RGD胡椒粉用荧光染料标记，将生物修饰的QD与传统的分子成像问题进行比较。为了充分表征QD-RGD共轭物的生物分布和药代动力学，我们将与Cu（T1/2 = 12.7 H）和64 124 I（T1/2 = 4.2 D）的新开发的QD-RGD结合物进行组合的NIR荧光和宠物成像。最后，基于CD和非CD的QD-RGD结合物将接受急性和慢性毒性研究。我们预计，新开发的非CD QD很少或没有毒性，可以进行临床翻译。这项研究对整合素AV¿3的RGD胡椒修饰的成功可以扩展到QD多路复用，以提供有关细胞表面标记的实时信息（表明恶性，肿瘤类型和潜在影响治疗）。这种信息对于正常过程和解散过程的分子特征的敏感，特异性和实时术中可视化对荧光引导的手术至关重要。在过去的二十年中，从纯电子材料科学到生物学应用，荧光半导体纳米晶体（又称量子点）已经发展。已经应用了各种涂料技术来使QDS生物相容性（水溶性和生物学上稳定）。适当连接的QD（通过抗体，蛋白质，胡椒粉或寡核苷酸）最常用于细胞生物学应用中，包括DNA阵列技术，免疫荧光测定。然而，到目前为止，用于分子成像的QD的制备已经严重发育不足。此外，基于镉的细胞毒性进一步阻碍了用于体内应用的此类纳米结构的发展。在此应用中，我们蓬勃发展，开发非镉的超小QD进行肿瘤血管生成成像。我们将开发并表征QD-RGD共轭物的库，然后进行体外和体内筛选。具有合适成像质量的QD将接受急性和慢性毒性研究。这种方法的成功将允许基于QD的探针进行荧光成像的临床翻译。