NOVEL STRATEGIES FOR THE IMMUNOTHERAPY OF COLON CANCER

描述：(改编自申请人的摘要)总体目标是 构建和优化新型人CEA DNA疫苗 结肠癌的免疫治疗。调查人员将检验这一假设 外周T细胞对这些肿瘤自身抗原的耐受性可以克服 通过设计产生细胞溶解T细胞的有效佐剂加强DNA疫苗 表达MHC-I类复合体的CEA表位特异性淋巴细胞(CTL) 对结肠癌细胞的影响。重点将放在优化抗原处理和 在转基因CEA或双转基因小鼠模型中的表达 CEA和人类白细胞抗原A2.1Kb。他们的目标是使用这样的模型来优化疫苗。 通过抗体-细胞因子融合蛋白和研究基本概念，如 T细胞共刺激、肿瘤特异性CTL和T细胞产生的机制 记忆细胞和建立过继免疫疗法的原则。具体的 为实现这些目标而设计的目标是：1)构建最理想的人 首先包含整个CEA基因的CEA特异性DNA疫苗，然后 编码具有人类白细胞抗原A*0201锚基残基的特定CEA多肽的微型基因。 通过注射裸KNA或口服疫苗的方式交付疫苗 减毒鼠伤寒沙门氏菌或单核细胞增多性李斯特氏菌； 2)20S蛋白酶体中抗原加工的优化和递呈 使用整个CEA基因的泛素化版本，编码几个 CEA非肽组织为一串珠子或直接靶向 单一CEA或重复表位进入内质网；3)实现 非甲基化CpG二核苷酸基序或CD40的最佳佐剂作用 配体/三聚体共表达；4)确定抗体-IL-2是否融合 蛋白质可以有效地促进DNA疫苗实现最佳、长寿 肿瘤保护性免疫，以及根除既定的转移，以及 免疫学机制的确定与肿瘤的发生 肿瘤特异性CTL和T记忆细胞。这项提案的实现 目标应该导致设计有效的DNA疫苗，基于 合理的免疫学原则，最终可能导致 结肠癌的治疗。

DESCRIPTION: (Adapted from applicant's abstract) The overall objective is to construct and optimize novel human CEA-based DNA vaccines for the effective immunotherapy of colon carcinoma. The investigators will test the hypothesis that peripheral T cell tolerance to these tumor self-antigens can be overcome by DNA vaccines boosted by effective adjuvants designed to generate cytolytic T lymphocyte (CTLs) specific for CEA epitopes expressed as MHC class I complexes on colon carcinoma cells. Emphasis will be on optimizing antigen processing and presentation in mouse models either transgenic for CEA or double transgenic for CEA and HLA-A2.1Kb. Their aim is to use such models for optimization of vaccine by antibody-cytokine fusion proteins and to investigate basic concepts such as mechanisms of T cell co-stimulation, generation of tumor-specific CTLs and T memory cells and establish principles for adoptive immunotherapy. The specific aims designed to achieve these objectives are: 1) construction of optimal human CEA-specific DNA vaccines containing first the entire CEA gene and then minigenes encoding specific CEA peptides with HLA-A*0201 anchor residues. Delivery of the vaccines by injction of naked KNA or orally by galvage using attenuated strains of either Salmonella typhimurium or Listeria monocytogenes; 2) optimization of antigen processing in the 20S proteasome and presentation by using ubiquitinated versions of the entire CEA gene, minigenes encoding several CEA nonapeptides organized as as a string of beads or direct targeting of single CEA or repeat epitopes to the endoplasmic reticulum; 3) achievement of optimal adjuvanticity using either unmethylated CpG dinucleotide motifs or CD40 Ligand/Trimer co-expression; and 4) determination whether antibody-IL2 fusion proteins can effectively boost DNA vaccines to achieve optimal, long-lived tumor-protective immunity, as well as eradicate established metastases, and identification of immunological mechanisms involved in generating tumor-specific CTLs and T memory cells. The achievement of this proposal's objectives should lead to the design of effective DNA vaccines based on rational immunological principles that may ultimately lead to the improved treatment of colon cancer.