ANTIGEN PRESENTATION DURING NUCLEIC ACID VACCINATION

核酸疫苗接种期间的抗原呈递

• 批准号: 2555254
• 负责人: Michael G Agadjanyan
• 金额: $ 23.87万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-30 至 1999-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2555254
• 关键词: AIDS vaccines; CD antigens; MHC class I antigen; active immunization; antigen presentation; antigen presenting cell; cell proliferation; cellular immunity; cytotoxic T lymphocyte; enzyme linked immunosorbent assay; flow cytometry; genetically modified animals; helper T lymphocyte; human immunodeficiency virus 1; humoral immunity; immunocytochemistry; laboratory mouse; muscle cells; mutant; polymerase chain reaction; site directed mutagenesis; vaccine development; vector vaccine

The overall goal of an immunization strategy is to induce specific immune responses which confer lifetime protection from the pathogen of interest. However, it is well known that the specific immune response required to provide such protection varies from one disease to the next. Nucleic acid immunization is a novel vaccination technique which induces antigen- specific immune responses. We have been interested in taking advantage of DNA vaccine technology to tailor immune responses according to the known correlates of protection for specific pathogens. As part of this effort, we developed expression cassettes for cell surface markers CD80 and CD86, two functionally related costimulatory molecules which play an important role in the induction of T cell-mediated immune responses. We co- immunized these expression plasmids along with plasmids DNA encoding for HIV-1 antigens and analyzed the magnitude of antigen-specific humoral and cellular immune responses. Although we did not see any significant change in the humoral response, we observed a dramatic increase in cytotoxic T lymphocyte (CTL) induction as well as T helper cell proliferation after the co-administration of CD86 genes. In contrast, co-immunization with a CD80 expression cassette resulted in a minor, but positive increase T helper cell or CTL responses. We have decided to ask a related question:can muscle be converted to a functional APC? For this experiment, we developed bone marrow chimeras, transferring bone marrow from beta-2 microglobulin (beta2m-/-) knockout mice into MHC identical C57BL/6J mice. These beta2m-/-mice lack expression of functional class I MHC molecules. The converse transfer was also performed. The chimerism was confirmed by flow cytometry, which showed more then 90% of peripheral blood cells class I positive in the beta2m+/+ -- more than beta2m-/- mice, with the beta2m -/- --more then beta2m+/+ mice showing less then 10% class I MHC expression. The functional absence of class I MHC molecules on the surface of APC in the beta2m -/- --more then beta2m+/+ mice let us ask whether we could functionally convert their muscle cells (which are class I MHC positive) into antigen presenting cells. Finally, using CD86/CD80 hybrid molecules we will identify in vivo functional region/s in the V- domains of human CD86 in enhancement of cellular immune responses to HIV envelop in mice. Different hybrids between CD80 and CD86 glycoproteins will be constructed using overlap PCR extension technique and they will be analyzed in vivo. The results will allow us to understand in general mechanism of antigen-presentation during DNA immunization, and specifically for construction of more powerful vaccine against AIDS.

免疫策略的总体目标是诱导特定的免疫。 提供对目标病原体的终生保护的应答。 然而，众所周知，所需的特异性免疫反应 提供的保护因疾病不同而不同。核酸 免疫是一种新的疫苗接种技术，它诱导抗原- 特定的免疫反应。我们一直有兴趣利用 DNA疫苗技术，根据已知的情况定制免疫反应 对特定病原体的保护的相关性。作为这一努力的一部分， 我们开发了细胞表面标记CD80和CD86的表达盒， 两个功能相关的共刺激分子发挥着重要的 在诱导T细胞介导的免疫反应中的作用。我们共同- 免疫这些表达载体和编码基因的DNA HIV-1抗原，并分析抗原特异性体液和 细胞免疫反应。尽管我们没有看到任何重大的变化 在体液反应中，我们观察到细胞毒性T细胞急剧增加 淋巴细胞(CTL)诱导及辅助性T细胞增殖 CD86基因的联合应用。相比之下，联合免疫与 CD80表达盒导致T细胞数量轻微增加，但呈正相关 辅助细胞或CTL反应。我们决定请一位相关的 问：肌肉可以转化为功能性的APC吗？为了这个 实验中，我们开发了骨髓嵌合体，将骨髓 从β-2微球蛋白(β2M-/-)基因敲除小鼠到MHC完全相同的小鼠 C57BL/6J小鼠。这些Beta2M-/-小鼠缺乏I类功能基因的表达 MHC分子。此外，还进行了反向转移。嵌合体 经流式细胞术证实，显示了90%以上的外周血细胞 在β2M+/+-小鼠中，血细胞I类阳性多于β2M-/-小鼠， 其中Beta2M-/-比Beta2M+/+小鼠表现出不到10%的等级 我的表情。第一类MHC分子在分子上的功能缺失 在Beta2m-/-比Beta2m+/+小鼠更多的APC表面让我们问 我们是否可以将他们的肌肉细胞(这是一类 I MHC阳性)转化为抗原提呈细胞。最后，使用CD86/CD80 杂化分子我们将在体内确定功能区/S在V- 人CD86结构域在增强HIV细胞免疫应答中的作用 笼罩在老鼠身上。CD80和CD86糖蛋白的不同杂交体 将使用重叠聚合酶链式反应延伸技术构建，它们将 在体内进行了分析。结果将使我们能够大体上了解 DNA免疫中的抗原提呈机制，以及 专门用于构建更强大的艾滋病疫苗。

项目成果

CD80 (B7-1) and CD86 (B7-2) are functionally equivalent in the initiation and maintenance of CD4+ T-cell proliferation after activation with suboptimal doses of PHA.

• DOI: 10.1089/10445490252925404
• 发表时间: 2002-03
• 期刊: DNA and cell biology
• 影响因子: 3.1
• 作者: V. Vasilevko;A. Ghochikyan;M. Holterman;M. Agadjanyan

CD86 (B7-2) can function to drive MHC-restricted antigen-specific CTL responses in vivo.

CD86 (B7-2) 可在体内驱动 MHC 限制性抗原特异性 CTL 反应。

• 发表时间: 1999
• 期刊: Journal of immunology (Baltimore, Md. : 1950)
• 作者: Agadjanyan,MG;Kim,JJ;Trivedi,N;Wilson,DM;Monzavi-Karbassi,B;Morrison,LD;Nottingham,LK;Dentchev,T;Tsai,A;Dang,K;Chalian,AA;Maldonado,MA;Williams,WV;Weiner,DB
• 通讯作者: Weiner,DB