HIV-1 DNA VACCINES THAT TARGET AND ACTIVATE CD40

针对并激活 CD40 的 HIV-1 DNA 疫苗

• 批准号: 6374712
• 负责人: JEFFREY A LEDBETTER
• 金额: $ 23.15万
• 依托单位: PACIFIC NORTHWEST RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6374712
• 关键词: AIDS vaccines; CD40 molecule; HIV envelope protein gp120; HIV envelope protein gp160; HIV envelope protein gp41; MHC class II antigen; Macaca nemestrina; antibody formation; antibody neutralization test; antibody titering; antigen presenting cell; cellular immunity; cytokine receptors; cytotoxic T lymphocyte; enzyme linked immunosorbent assay; helper T lymphocyte; human immunodeficiency virus 1; human tissue; humoral immunity; neutralizing antibody; plasmids; receptor expression; vector vaccine; virus antigen; virus protein

HIV-1 DNA vaccines induce both humoral and cellular immune responses in experimental animals, suggesting their potential usefulness for immunization. However, further optimization of DNA vaccines is needed to induce protection against virulent HIV-1 isolates. We propose to utilize CD40 activation and targeting in an attempt to improve the ability of HIV-1 env DNA vaccines to generate strong cellular immunity and high titers of neutralizing antibodies. We will construct DNA vaccines encoding CD40 ligand (CD154) or a single chain Fv (scFv) specific for CD40, fused with DNA encoding portions of the HIV-1 env protein. After DNA vaccination, the expression of this fusion protein in vivo could result in both activation of the CD40 receptor and direction of HIV-1 env antigens into the endocytic pathway of CD40 positive antigen presenting cells (APC). Internalization of env antigens after binding the CD40 positive antigens presenting cells (APC). Internalization of env antigens after binding the CD40 receptor will enhance presentation of peptides to effective antibody production and generation of CD4+ helper T cell and CD8+CTL activity. We hypothesize that the combination of CD40 activation and presentation of viral peptides by MHC class II will lead to improved immune responses to viral antigens. This hypothesis will be tested by construction of anti-human CD40 scFv-env DNA vaccines, followed by testing in primates where the anti-human CD40 scFv and human CD154 retain CD40 binding and functional activity. Antibody responses towards HIV-1 env will be tested by epitope specific ELISA assays and viral neutralization assays.

HIV-1 DNA疫苗在实验动物中诱导体液免疫和细胞免疫应答，表明它们在免疫方面的潜在用途。然而，需要进一步优化DNA疫苗以诱导针对毒性HIV-1分离株的保护。我们建议利用CD 40活化和靶向，试图提高HIV-1 env DNA疫苗产生强细胞免疫和高滴度中和抗体的能力。我们将构建编码CD 40配体（CD 154）或CD 40特异性单链抗体（scFv）的DNA疫苗，与编码HIV-1 env蛋白部分的DNA融合。DNA疫苗接种后，该融合蛋白在体内的表达可导致CD 40受体的活化和HIV-1 env抗原进入CD 40阳性抗原呈递细胞（APC）的内吞途径。env抗原结合CD 40阳性抗原呈递细胞（APC）后的内化。结合CD 40受体后env抗原的内化将增强肽的呈递以有效产生抗体和产生CD 4+辅助T细胞和CD 8 +CTL活性。我们推测，CD 40活化和通过MHC II类呈递病毒肽的组合将导致对病毒抗原的免疫应答改善。将通过构建抗人CD 40 scFv-env DNA疫苗，然后在灵长类动物中进行测试，其中抗人CD 40 scFv和人CD 154保留CD 40结合和功能活性，来测试该假设。针对HIV-1 env的抗体应答将通过表位特异性ELISA测定和病毒中和测定进行检测。