Dna Immunogens

DNA免疫原

• 批准号: 6534942
• 负责人: Jack Ragheb
• 金额: --
• 依托单位: NATIONAL EYE INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6534942
• 关键词: AIDS vaccines; HIV envelope protein; autoimmune disorder; autoimmunity; genetic manipulation; human immunodeficiency virus; laboratory mouse; laboratory rat; microorganism immunology; nonhuman therapy evaluation; oral tolerance; retinoid binding proteins; transfection /expression vector; uveitis; vaccine development; vector vaccine

DNA Immunogens A. DNA Based Induction of Autoimmune Disease In the last several years it has been demonstrated that bacterial DNA itself is a potent adjuvant and that it can be used as a vaccine to induce immune responses (to protein antigens encoded by the DNA) that are sufficient to confer protective immunity against a number of pathogens. These observations suggest that so called DNA vaccines could also be used to induce autoimmune disease in various animal models. One advantage of this previously untested approach is that it allows for the rapid screening of candidate immunogens (in their DNA form) by circumventing the need to isolate protein. This is particularly advantageous when it is very difficult to obtain sufficient quantities of purified human proteins to use as immunogens. As a first test of this approach we are attempting to establish a DNA vaccine based model of experimental autoimmune uveitis. To date we have shown in rodents that a DNA vaccine encoding human IRBP administered via the SQ, ID, or IM routes elicits a good immune response to the encoded antigen and that the immunized rats, but interestingly not the mice, develop disease. We are presently working to improve the responses that we?ve obtained in rats and extend them to the mouse. Investigations into the basis of the dichotomy between immune response and disease pathogenesis in the mouse should lend further insight into the variables that are responsible for disease penetrance. B. HIV Vaccine Not long ago, HIV infection was an important cause of morbidity and mortality in the United States. The advent of highly active anti-retroviral therapy (HAART) is entirely responsible for the decline in HIV associated disease in this country. However, there is already evidence that viral resistance to HAART has emerged, suggesting that we may see a return of AIDS. It is clear that the long term solution to HIV infection must include the development of an effective vaccine. For safety reasons, efforts to develop a vaccine have focused on using the recombinant protein subunit components of the virus. However, HIV is a heavily glycosylated virus and the complex carbohydrate structures that are present on its surface are likely to mask important epitopes. Along with investigators at the University of Pennsylvania, we are exploring an alternative strategy to generate immune responses against HIV associated carbohydrate antigens. Our collaborator has identified short peptide sequences that elicit humoral immune responses that strongly cross react with certain carbohydrates. To test whether such anti-carbohydrate responses can enhance an anti-HIV immune response, we are genetically engineering these so called peptide mimetope sequences into the HIV envelope gene and using gene therapy vectors to introduce the encoded altered HIV envelope protein into mouse B cells. The immune response to the altered HIV envelope can then be assessed after transfer of the transduced B cells to a syngenic host. To date we have generated peptide mimetope containing HIV envelope constructs and are in the process of introducing them into mouse B cells.

DNA免疫剂A.在过去几年中，基于DNA的自身免疫性疾病的诱导症表明，细菌DNA本身是一种有效的辅助剂，可以用作疫苗来诱导免疫反应（对DNA编码的蛋白质抗原）（由DNA编码），足以赋予抗pathogementotecongotenotemengemengementy的保护性免疫。这些观察结果表明，在各种动物模型中，所谓的DNA疫苗也可以用来诱导自身免疫性疾病。这种以前未经测试的方法的优点是，它可以通过规避分离蛋白质的需求来快速筛选候选免疫原（以其DNA形式）。当很难获得足够数量的纯化人蛋白来用作免疫原子时，这尤其有利。作为这种方法的第一个测试，我们正在尝试建立基于DNA疫苗的实验自身免疫性葡萄膜炎模型。迄今为止，我们已经在啮齿动物中表明，通过SQ，ID或IM路线施用人IRBP的DNA疫苗会引起对编码抗原的良好免疫反应，并且免疫性大鼠，但有趣的不是小鼠，但不是小鼠发展疾病。目前，我们正在努力改善我们在大鼠中获得的反应并将其扩展到鼠标。对小鼠免疫反应和疾病发病机理之间二分法的研究应进一步深入了解导致疾病渗透率的变量。 B.艾滋病毒疫苗不久前，艾滋病毒感染是美国发病率和死亡率的重要原因。高度活跃的抗逆转录病毒疗法（HAART）的出现完全是该国艾滋病毒相关疾病下降的原因。但是，已经有证据表明对Haa​​rt的病毒抵抗已经出现，这表明我们可能会看到艾滋病的回归。显然，艾滋病毒感染的长期解决方案必须包括开发有效的疫苗。出于安全原因，开发疫苗的努力专注于使用该病毒的重组蛋白亚基成分。然而，HIV是一种严重的糖基化病毒，其表面上存在的复杂碳水化合物结构可能掩盖了重要的表位。与宾夕法尼亚大学的研究人员一起，我们正在探索一种针对HIV相关碳水化合物抗原的免疫反应的替代策略。我们的合作者已经确定了短肽序列，这些肽序列引起了与某些碳水化合物反应强烈反应的体液免疫反应。为了测试这种抗碳水化合物反应是否可以增强抗HIV免疫反应，我们在遗传上将这些所谓的肽Mimetope序列在HIV包膜基因中进行了研究，并使用基因治疗载体将所编码的改变的HIV HIV HIV蛋白质引入小鼠B细胞中。然后可以评估转导的B细胞向合成宿主转移后，可以评估对改变的HIV包膜的免疫反应。迄今为止，我们已经生成了含有HIV包膜构建体的肽模拟物，并且正在将其引入小鼠B细胞中。