Bacterial vector vaccine: Her-2/neu expressing tumors

描述（由申请人提供）：Advaxis将开发一种针对人HER-2/neu蛋白的新型单核细胞增生李斯特菌疫苗，这将是一种安全有效的治疗性疫苗，用于治疗HER-2/neu过表达的乳腺癌。乳腺癌是女性中最常见的癌症类型，是一种复杂的疾病，没有单一的病原体或事件。有几种肿瘤相关抗原与乳腺癌有关。其中，HER-2/neu癌基因产物特别令人感兴趣，因为它在大约三分之一的乳腺腺癌中过表达，并与转移性疾病和不良预后相关。单核增生李斯特菌是一种兼性细胞内细菌，在许多抗原呈递细胞的细胞质中感染和增殖，已被确定为治疗性疫苗载体。这些载体已被证明在许多疾病模型（如艾滋病毒感染和癌症）中增强细胞介导的免疫反应是强有力的。我们建议采用一种新的方法来产生基于单核细胞增生乳杆菌的疫苗，以对抗内源性表达的人类基因HER-2/新肿瘤相关抗原。我们建议在符合FDA指南的载体中这样做，因为它不会包含任何抗生素抗性基因。我们将在2个FVB乳腺癌小鼠模型中展示肿瘤控制。此外，我们将证明这些疫苗诱导特异性CD8+ T细胞对HER-2/ new抗原的反应。具体而言，该I期计划将产生不含抗生素抗性基因的减毒重组单核增生乳杆菌疫苗载体，并将分泌可检测水平的LmDA(-)-LLO-HER-2/neu融合蛋白。将产生五种不同的含有人HER-2/neu基因片段的构建体，每种构建体含有p185人HER-2/neu细胞外或细胞内结构域的不同片段(LmDA(-)- llo - eci, LmDA(-)- llo - ec2, LmDA(-)- llo - ec3, LmDA（-)- LLO-IC1, LmDA(-)- llo - ic2）。此外，我们建议证明这些构建体在HLA-A2转基因小鼠中诱导HER-2/ new特异性CD8+ T细胞反应的能力。这项工作将证明以单核细胞原乳杆菌为基础的疫苗的效用，从而为进一步开发可用于人类的乳腺癌治疗方法奠定基础。

DESCRIPTION (provided by applicant): Advaxis will develop a novel Listeria monocytogenes based vaccine against the human HER-2/neu protein that will be a safe and effective therapeutic vaccine for the treatment of HER-2/neu overexpressing breast carcinomas. Breast cancer, the most common type of cancer in women, is a complex disease with no single causative agent or event. There are several tumor-associated antigens associated with breast cancer. Of these, the HER-2/neu oncogene product is of particular interest because it is overexpressed in approximately one-third of breast adenocarcinomas and is associated with metastatic disease and poor prognosis. Listeria monocytogenes, a facultative intracellular bacterium that infects and proliferates in the cytoplasm of a number of antigen presenting cells has been identified as a therapeutic vaccine vector. These vectors have proven to be powerful in boosting cell mediated immune responses in a number of disease models such as HIV infection and cancer. We propose to take the novel approach of generating L. monocytogenes-based vaccines against the endogenously expressed human gene, the HER-2/neu tumor associated-antigen. We propose to do this in a vector that meets FDA guidelines in that it will not contain any antibiotic resistance genes. We will demonstrate tumor control in 2 FVB mouse models for breast cancer. Furthermore, we will demonstrate that these vaccines induce specific CD8+ T cell responses against the HER-2/neu antigen. Specifically, this Phase I proposal will generate attenuated recombinant L. monocytogenes vaccine vectors that contain no antibiotic resistance genes and will secrete detectable levels of LLO-HER-2/neu fusion proteins (LmDA(-)-LLO-HER-2/neu). Five different constructs containing the Human HER-2/neu gene fragments will be generated, each one containing a different fragment of the p185 human HER-2/neu extracellular or intracellular domain (LmDA(-)-LLO-ECI, LmDA(-)-LLO-EC2, LmDA(-)-LLO-EC3, LmDA(-)- LLO-IC1, LmDA(-)-LLO-IC2). Additionally, we propose to demonstrate the ability of each of these constructs to induce a HER-2/neu specific CD8+ T cell response in the HLA-A2 transgenic mice. This work will demonstrate the utility of the L. monocytogenes-based vaccines, thus setting the stage for further development of a breast cancer therapeutic that can be used in humans.