HIV-1 Gene Products/Targeted/MHC II Antigen Presentation

该项目目标是开发一种全球应用的人类HIV-1基因(DNA)疫苗， 将包括有效疫苗的以下要素：(1)与超型人相结合的HIV-1序列 淋巴细胞抗原(HLA)，代表全球人口的大多数。(2)HIV-1序列 这代表了全球艾滋病毒-1基因型别和所有主要分支的人口。(3)一种疫苗， 刺激免疫系统的所有手臂，并激发对艾滋病毒挑战的免疫记忆。 研究设计是基于DNA疫苗嵌合体和选定的HIV-1 T细胞表位序列 插入溶酶体相关膜蛋白(LAMP)的管腔结构域，并靶向于 含有主要组织相容性II类(MHC II)蛋白的抗原提呈细胞(ARC)的细胞器 用于将抗原表位呈递给CD4+T细胞并激活免疫记忆。目标锁定 已知MHC II隔室的内源性抗原刺激T细胞和B细胞反应，并 免疫记忆。通过对所有HIV-1基因组序列进行计算机建模来进行表位选择 选择在A到D分支中保守的、包含多个、主要是 与HLA超类型等位基因结合的重叠的非序列多肽序列(热点)。这些超类型 表示在其结合槽中具有细微差异的一组HLA等位基因 占人类人口的很大比例。所选序列对T细胞激活的验证数据为 用编码MHC II靶向的DNA构建物免疫人类白细胞抗原转基因小鼠 跨表位重叠多肽的序列测定及表位特异性T细胞反应分析 热点序列。选定的HIV-1序列与人类免疫反应的进一步相关性将是 与其他研究人员合作进行ELISpot分析体外T细胞对 各主要分支HIV-1感染患者白细胞的部分肽序列。此外， 所选表位序列的生物学作用将用小鼠黄热病病毒模型进行分析 (YFV)挑战检测系统。LAMP/HIV表位嵌合体免疫的保护作用 通过用含有相同HIV序列的YFV攻击免疫动物进行检测。 相关性：该项目提出了应用新技术来开发有效的 HIV-1疫苗适用于全球人群和所有主要的HIV-1分支，并能够诱导免疫 记忆。

The objective of this project is to develop a human HIV-1 genetic (DNA) vaccine for global application that will include the following elements of an effective vaccine: (1) HIV-1 sequences that bind to supertype human lymphocyte antigens (HLA) that represent the majority of global human populations. (2) HIV-1 sequences that represent the global population of HIV-1 genotypes and all the major clades. (3) A vaccine that stimulates all arms of the immune system and elicits immune memory to HIV challenge. The research design is based on DNA vaccine chimeras with selected HIV-1 T cell epitope sequences inserted into the luminal domain of the lysosome-associated membrane protein (LAMP) and targeted to organelles of antigen presenting cells (ARC) that contain major histocompatability class II (MHC II) proteins for presentation of antigen epitopes to CD4+ T-cells and activation of immune memory. Targeting of endogenous antigens to the MHC II compartment is known to stimulate both T- and B-cell responses and immune memory. Epitope selection is conducted by computer modeling of all HIV-1 genome sequences with algorithms that select protein sequences that are conserved in clades A to D and contain multiple, mostly overlapping, nonameric peptide sequences (hotspots) that bind to HLA supertype alleles. These supertypes represent groups of HLA alleles that have subtle differences in their binding grooves and are present in a large proportion of the human population. Validaton of T-cell activation by the selected sequences is conducted by immunizing HLA transgenic mice with DNA constructs encoding the MHC II- targeted sequences and analyzing epitope-specific T-cell responses with overlapping peptides spanning the epitope hotspot sequences. Further correlation of the selected HIV-1 sequences to human immune responses will be in collaboration with other investigators to carry out ELISpot analysis of the ex vivo T-cell responses to the selected peptide sequences of leucocytes of patients infected by HIV-1 of all major clades. Additionally, the biological role of the selected epitope sequences will be analyzed with a mouse model yellow fever virus (YFV) challenge assay system. The protective effect of immunization with the LAMP/HIV epitope chimera will be assayed by challenging the immunized animal with YFV containing the same HIV sequence. Relevance: This project proposes the application of novel technologies to the development of an effective HIV-1 vaccine applicable to global populations and all major HIV-1 clades, and capable of eliciting immune memory.