Self-assembling protoviral nanoparticles

自组装原病毒纳米颗粒

基本信息

批准号：
10262281
负责人：
Nadya Tarasova
金额：
$ 7.59万
依托单位：
DIVISION OF BASIC SCIENCES - NCI
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10262281
关键词：
Adopted Agreement Antineoplastic Agents Asthma Attention Biological Biological Availability Bombesin Receptor CC chemokine receptor 3 CXCR4 Receptors CXCR4 gene Cell Surface Receptors Cell fusion Cell membrane Cells Development Disease Drug Delivery Systems Effectiveness Encapsulated FOLH1 gene Fluorescence Generations Geometry Goals Hepatotoxicity Heterogeneity Hydrophobicity Image Ligands Liver Luteinizing Hormone Mammary Neoplasms Mediating Metastatic Neoplasm to the Lung Methods Molecular Molecular Conformation Mus Pathogenesis Peptide Receptor Peptides Permeability Pharmaceutical Preparations Play Polyethylene Glycols Prostatic Neoplasms Receptor Signaling Reproducibility Role Signal Transduction Structure Surface Properties System Testing Therapeutic Uses Toxic effect Treatment Cost Tumor Tissue Ultracentrifugation Virus Virus-like particle alpha helix aqueous base clinical application design drug development human model improved inhibitor/antagonist light scattering mouse model nanomolar nanoparticle neoplastic cell overexpression particle prevent prostate cancer cell receptor self assembly systemic toxicity tomography tumor uptake virus development

项目摘要

Significant efforts have been devoted to the development of nanoparticular delivering systems targeting tumors. However, clinical applications of nanoparticles is hampered by insufficient size homogeneity, difficulties in reproducible synthesis and manufacturing, frequent high uptake in the liver, systemic toxicity of the carriers (particularly for inorganic nanoparticles) and insufficient selectivity for tumor cells. We have recently discovered the ability of properly modified transmembrane peptides to assemble into remarkably uniform spherical nanoparticles with innate biological activity. Self-assembly is driven by a structural transition of the peptide that adopts predominantly a beta-hairpin conformation in aqueous solutions, but folds into an alpha-helix upon spontaneous fusion with cell membrane. Alpha-helical peptide interferes with proper assembly of the target receptor and inhibits its function. The best characterized antagonist inhibits signaling through CXCR4 inhibitor with IC50=100 nM. Addition of polyethylene glycol (PEG) chains of up to 27 monomeric units stabilizes nanoparticles and prevents their super-aggregation without interfering with biological activity. Longer PEG chains diminish efficient fusion of nanoparticles with the cell membrane and reduce anti-receptor activity.The peptide self-assembles with such high efficiency that critical self-assembly concentration (CAC) could not be determined by traditional methods, such as dynamic light scattering, ultracentrifugation or viscosimetry. We have developed a new method of CAC determination based on Microscale Thermophoresis. The determined CAC is in nanomolar range for all peptides tested, in good agreement with observed high precision of self-assembly and stability of the nanoparticles. Nanoparticles efficiently encapsulate poorly soluble hydrophobic drugs, thus providing a unique delivery system with dual anti-tumor activity. Even empty nanoparticles effectively inhibit lung metastasis in a mouse model of human breast tumor, due to their ability to inhibit CXCR4 receptor signaling. We have now developed nanoparticles that fuse with cells in receptor-mediated manner, similar to viruses. Conjugates of self-assembling peptide to ligands of receptors overexpressed on prostate tumors resulted in nanoparticles that fuse more effectively with cells expressing corresponding receptor. Self-assembling virus-like particles with intrinsic biological activity present a new paradigm in anti-cancer drug development. We have now generated fully synthetic self-assembling nanoparticles that fuse with cells in receptor-mediated manner, like natural viruses. Synthetic particles were designed to fuse with cells through three receptors over expressed on prostate tumor cells: gastrin-releasing peptide receptor, luteinizing hormone releasing peptide receptor and prostate-specific membrane antigen. All three synthetic virus-like particles have been shown to fuse with cells very selectively: blocking the corresponding receptor with its ligand completely prevents cell fusion. Fluorescence tomography studies in mice have demonstrated that new fully synthetic virus-like particles localize to prostate tumors with high efficiency and selectivity. The particles are promising agents for both imaging and therapy of prostate tumors. We have also developed recently self-assembling antagonists of CCR3 receptor that plays a critical role in pathogenesis of asthma. The compounds are promising agents for the treatment of the disease.

大量努力致力于开发针对肿瘤的纳米关节输送系统。然而，纳米颗粒的临床应用受到尺寸不足的同质性，可重复的合成和制造的困难，肝脏（尤其是对无机纳米颗粒的全身性毒性）的频繁吸收，对肿瘤细胞的选择性不足。最近，我们发现了正确修饰的跨膜肽的能力，可以将具有先天生物学活性的球形纳米颗粒组装成非常均匀的球形纳米颗粒。自组装是由肽的结构过渡驱动的，该肽主要在水溶液中采用β发质构象，但与细胞膜自发融合后折叠成α-螺旋。 α-螺旋肽会干扰目标受体的适当组装并抑制其功能。最佳特征拮抗剂可以通过IC50 = 100 nm的CXCR4抑制剂抑制信号传导。高达27个单体单元的聚乙烯乙二醇（PEG）链稳定纳米颗粒并防止其超级聚集，而不会干扰生物学活性。较长的PEG链降低了纳米颗粒与细胞膜的有效融合，并降低抗受体活性。具有高效率的肽自我组装，以至于无法通过传统方法（例如动态光散射，超耐渗漏或粘液液）来确定关键自组装浓度（CAC）。我们已经开发了一种基于微观嗜热的新方法的CAC测定方法。确定的CAC在所有测试的肽的纳摩尔范围内，与观察到的纳米颗粒的自组装和稳定性的高精度非常吻合。纳米颗粒有效地封装了溶解度较差的疏水性药物，从而提供了具有双重抗肿瘤活性的独特递送系统。即使是空的纳米颗粒，由于它们能够抑制CXCR4受体信号传导的能力，因此在人类乳腺肿瘤的小鼠模型中也有效抑制了肺转移。现在，我们已经开发了与病毒相似的受体介导方式与细胞融合的纳米颗粒。自组装肽与前列腺肿瘤过表达的受体配体的结合物导致纳米颗粒与表达相应受体的细胞更有效地融合。具有内在生物学活性的自组装类型的病毒样颗粒具有抗癌药物开发的新范式。现在，我们已经产生了完全合成的自组装纳米颗粒，这些纳米颗粒以受体介导的方式（如天然病毒）与细胞融合在一起。设计的合成颗粒是通过在前列腺肿瘤细胞上表达的三个受体与细胞融合的：胃蛋白释放肽受体，黄体生成激素释放的肽受体和前列腺特异性膜抗原。所有三个合成病毒样颗粒都非常有选择地与细胞融合：与其配体阻断相应的受体完全防止了细胞融合。在小鼠中进行的荧光断层扫描研究表明，新的完全合成病毒样颗粒将效率高的前列腺肿瘤定位为前列腺肿瘤。这些颗粒是前列腺肿瘤成像和治疗的有希望的药物。我们还开发了CCR3受体的近来自组装拮抗剂，在哮喘的发病机理中起着至关重要的作用。这些化合物是治疗疾病的有前途的药物。