SINGLE CHAIN HIV GP120-CD4 COMPLEX

描述：(改编自申请者摘要)HIV的约束力 囊膜糖蛋白gpl20与其细胞表面受体cd4结合，暴露出新的 “依赖于复合体”的gpl20表位，可引起中和抗体反应。 这些表位位于与7跨膜结合的gpl20结构域中。 跨越病毒进入所需的辅助受体。有证据表明依赖于复合体 我们早期的研究提供了表位可能是重要的疫苗靶点 结果表明：1)共价交联的gp120-CD4复合体可广泛诱导 中和针对艾滋病毒主要分离株的体液反应。根据这一规定， 含有构象改变的gpl20的“融合能力”免疫原 通过细胞表面受体结合，最近显示出广泛的诱导性 中和针对多种HIV分离株的体液反应 不同的基因分支。这些结果为疫苗的开发提供了依据 提高体液和细胞对复杂依赖的反应的策略 表位。我们的假设是，这可以通过构建 Gpl20与CD4共价连接的单链嵌合分子 通过多肽连接物。在这份申请中，我们提供了初步证据 表明这种复合体由编码的核苷酸序列表达 密码子优化的gpl20和可溶性CD4。为了评估我们的假设，我们 建议进一步开发和表征这些分子，并评估它们的 DNA疫苗和亚单位疫苗的免疫原性。这项工作 将以两个具体目标进行。第一个将包括制作和 表达可溶性单链CD4-gpl20的构建体的特性 M-向性体(R5)、双向性体(R5X4)和T-向性体(X4)的配合物 病毒。第二个目标是评估单链的免疫原性。 人CD4转基因小鼠体内的CD4-gpl20复合体。这项工作应该提供新的 对艾滋病毒疫苗具有重大实用和科学意义的数据 发展。

DESCRIPTION: (Adapted from Applicant's Abstract) The binding of the HIV envelope glycoprotein, gpl20, to its cell surface receptor, CD4, exposes novel "complex-dependent" gpl20 epitopes that elicit neutralizing antibody responses. These epitopes are situated in a gpl20 domain that binds 7 transmembrane spanning co-receptors needed for virus entry. Evidence that complex-dependent epitopes might be important vaccine targets was provided by our early studies showing: 1) that covalently crosslinked gp120-CD4 complexes elicit broadly neutralizing humoral responses against primary HIV isolates. In accordance, "fusion competent" immunogens containing gpl20 that is conformationally altered by cell surface receptor binding were recently shown to elicit broadly neutralizing humoral responses against a wide variety of HIV isolates from different genetic clades. These results warrant the development of vaccine strategies to raise humoral and cellular responses against complex dependent epitopes. Our hypothesis is that this can be accomplished by constructing single chain chimeric molecules comprised of gpl20 and CD4 covalently attached by a polypeptide linker. In this application, we provide preliminary evidence showing that such complexes are expressed from nucleotide sequences encoding codon-optimized gpl20 and soluble CD4. In order to evaluate our hypothesis, we propose to further develop and characterize these molecules, and evaluate their immunogenic properties in the contexts of DNA and subunit vaccines. The work will proceed with two specific aims. The first will include the production and characterization of constructs that express soluble, single-chain CD4-gpl20 complexes from M-tropic (R5), dual-tropic (R5X4) and T-tropic (X4) primary viruses. The second Aim will be to evaluate the immunogenicity of single chain CD4-gpl20 complexes in human CD4 transgenic mice. This work should provide new data with significant practical and scientific relevance to HIV vaccine development.