Improved Tumor Targeting of Salmonella VNP20009 via Ice-llama Antibody Guidance

通过 Ice-llama 抗体指导改进沙门氏菌 VNP20009 的肿瘤靶向

基本信息

批准号：
8492399
负责人：
ANDREW HAYHURST
金额：
$ 19.9万
依托单位：
TEXAS BIOMEDICAL RESEARCH INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-04-01 至 2015-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8492399
关键词：
3-Dimensional Adverse effects Animal Model Antibiotics Antibodies Attenuated Bacteria Benchmarking Binding Bioluminescence Breast Cancer Cell Cancer Patient Cancer cell line Carcinoembryonic Antigen Cause of Death Cell Culture Techniques Cell surface Cells Cessation of life Colony-forming units Diagnosis Drug Delivery Systems Engineering Enzyme-Linked Immunosorbent Assay Equilibrium Fluorescence Microscopy Gastrointestinal Neoplasms Gene Fusion Genetic Goals Growth Heart Diseases Human Ice Immunohistochemistry In Situ In Vitro Link Llama Longitudinal Studies MCF7 cell Malignant Neoplasms Measurement Mediating Membrane Proteins Metastatic Melanoma Modeling Molecular Monitor Nanostructures Necrosis Organ Outcome Patients Plasmids Proteins Radio Resistance Salmonella Salmonella enterica Solutions Staging Surface System Therapeutic Time Tissue Harvesting Titrations Toxic effect Tumor Cell Invasion Tumor Markers Virus Woman Xenograft Model antigen binding base design improved in vivo luminescence malignant breast neoplasm mouse model neoplastic cell public health relevance research study tumor

项目摘要

DESCRIPTION (provided by applicant): ABSTRACT While Salmonella VNP 20009 (VNP) has shown promise in tumor targeting in animal models it is becoming apparent that regrowth of tumors is the outcome since the bacteria preferentially grow in the necrotic core and fail to reach the vital periphery. In human trials of metastatic melanoma patients, even targeting itself was very poor and no tumor regression was observed. We aim to improve the tumor targeting and tumor regressive ability of VNP by conferring upon it the successful recognition potential of antibody mediated tumor targeting. We had previously attempted to do this using the lpp-OmpA surface display platform and poorly soluble scFv antibodies but have since found out that the combination caused bacterial growth arrest and restricted the therapeutic potential of engineered VNP. We hypothesize that VNP displaying small and highly soluble anti- CEA single domain antibodies via the ice nucleation protein (INP) will show enhanced targeting of CEA positive tumors without inhibiting bacterial invasion or replication and will therefore be able to regress tumors more effectively than parental VNP. Our specific aims are to; 1, Engineer VNP to display anti-CEA sdAb without impeding replication, yet capable of binding immobilized CEA in vitro; 2, Demonstrate engineered VNP is capable of being internalized in MCF-7 cells and is also capable of homogenous targeting in three- dimensional spheroidal cell culture models; 3, Demonstrate improved in vivo tumor targeting of engineered VNP in a mouse model of breast cancer, elucidating intra-tumoral distribution and potential for complete tumor regression. The multifunctional capabilities of VNP including mobility and ability to carry large payloads are well balanced by the ability to visualize single bioluminescent cells and facile elimination of the bacteria by antibiotics. As such, the potential for VNP as a highly controllable yet versatile cancer therapeutic is enormous so long as we can improve targeting and regressive capacity.

描述（由申请人提供）：摘要虽然沙门氏菌 VNP 20009 (VNP) 在动物模型中显示出肿瘤靶向的前景，但越来越明显的是，肿瘤的再生是结果，因为细菌优先在坏死核心中生长，无法到达重要的外围。在转移性黑色素瘤患者的人体试验中，即使靶向本身也很差，并且没有观察到肿瘤消退。我们的目标是通过赋予VNP抗体介导的肿瘤靶向的成功识别潜力来提高VNP的肿瘤靶向和肿瘤消退能力。我们之前曾尝试使用 lpp-OmpA 表面展示平台和难溶性 scFv 抗体来做到这一点，但后来发现这种组合会导致细菌生长停滞并限制工程化 VNP 的治疗潜力。我们假设，通过冰核蛋白（INP）展示小且高度可溶的抗CEA单域抗体的VNP将显示出对CEA阳性肿瘤的增强靶向性，而不抑制细菌侵袭或复制，因此能够比亲本VNP更有效地消退肿瘤。我们的具体目标是； 1、工程化VNP以展示抗CEA sdAb而不妨碍复制，但能够在体外结合固定化的CEA； 2、证明工程化VNP能够内化于MCF-7细胞中，并且能够在三维球状细胞培养模型中同质靶向； 3、在乳腺癌小鼠模型中证明工程化 VNP 的体内肿瘤靶向性得到改善，阐明肿瘤内分布和肿瘤完全消退的潜力。 VNP 的多功能能力（包括机动性和运载大有效载荷的能力）非常出色通过可视化单个生物发光细胞的能力和通过抗生素轻松消除细菌的能力来平衡。因此，只要我们能够提高靶向和回归能力，VNP 作为一种高度可控且多功能的癌症治疗方法的潜力是巨大的。