QUANTITATIVE ANALYSIS OF IMMUNITY TO VIRAL IMMUNOGENS

病毒感染是老年人重要的病原体。免疫反应在保护个体免受致命病毒感染方面起着重要作用。有证据表明，老年啮齿动物和人类的T细胞功能都受到损害。我们的假设是饮食限制（DR）可以预防衰老引起的缺陷。因此，我们将利用新颖的定量分析，在相关的灵长类动物模型——恒河猴中检验这一假设。因此，我们将量化年轻、对照（老年）和饮食限制（DR）恒河猴对疫苗接种的细胞免疫反应。在过去五年的NIH支持下，我们通过定义主要组织相容性复合体（MHC）的等位基因和位点，并开发基于序列的恒河猴MHC I类和II类等位基因的MHC分型，增加了恒河猴作为非人类灵长类动物模型的价值，用于研究对重要人类病原体的免疫反应。我们还开发了分析病毒特异性细胞毒性T淋巴细胞（CTL）的技术，Altman博士开发了一种测定CTL前体频率的新技术。我们有独特的优势来测试关于衰老和DR对体内病毒感染的细胞免疫反应的影响的重要假设。因此，我们将使用这些新技术来分析免疫恒河猴的T细胞反应，以了解年龄和DR对病毒感染的细胞免疫反应的影响。核心提供的独特动物群代表了宝贵的动物资源，这将使我们能够测试有关衰老和DR在病毒感染中对灵长类免疫反应的作用的假设。在特异性目标I中，我们将描述CD8+ T细胞对猴免疫缺陷病毒（SIV）的反应，在10只健康的年轻MHC I类定义恒河猴中。这将导致至少4个新的免疫显性CTL表位的描述，这些表位与常见的恒河猴MHC I类分子结合。我们将利用这些表位在特异性Aim II中构建免疫原。在特异性靶II中，我们将定量CD8+ T细胞对CTL表位接种的反应。我们还将监测对乙型肝炎病毒（HBV）核心抗原的增殖和抗体反应。这将使我们能够评估衰老和DR对年轻、对照（老年）和受限动物的CD8、CD4和B细胞区室的影响。因此，在1、2和3组的对照和限制性动物队列中，我们将确定衰老是否会影响免疫反应，以及DR是否可以改变这一点。

Viral infections are important pathogens in the elderly. Immune response play a major role in protecting individuals from lethal infection with viruses. Evidence suggests that T cell function is compromised in both old rodents and humans. Our hypothesis is that dietary restriction (DR) can prevent the deficiencies induced by aging. We will, therefore, utilize novel, quantitative analyses to test this hypothesis in a relevant primate model, the rhesus macaque. Thus, we will quantitate the cellular immune response to vaccination in young, control (old) an dietary restricted (DR) rhesus macaques. Over the last five years of NIH support, we have increased the value of the rhesus macaque as a non-human primate model for studying the immune response to important human pathogens by defining the alleles and loci of the major histocompatibility complex (MHC) and developing sequence-based MHC typing of the rhesus-macaque MHC class I and II alleles. We have also developed technologies for the analysis of virus-specific cytotoxic T lymphocytes (CTLs) and Dr. Altman has developed a novel technology for determining CTL precursor frequencies. We are uniquely positioned to test important hypotheses concerning the effect of aging and DR on the cellular immune response to virus infection in vivo. We will, therefore, use these novel technologies for analyzing the T cell response in immunized rhesus macaques to understand the effects of age and DR on the cellular immune response to virus infection. The unique cohort of animals provided by the core represents an invaluable resource of animals that will allow us to test hypotheses concerning the role of aging and DR on the immune response of primates in virus infection. In Specific Aim I, we will describe the CD8+ T cell response to the simian immunodeficiency virus (SIV) in ten healthy, young MHC class I-defined rhesus macaques. This will result in the description of at least 4 new immunodominant CTL epitopes that bind to common rhesus MHC class I molecules. We will use these epitopes in the construction of immunogens in Specific Aim II. In Specific Aim II, we will quantitate the CD8+ T cell response to CTL epitope vaccination. We will also monitor the proliferative and antibody response to the hepatitis B virus (HBV) core antigen. This will allow us to assess the effect of aging and DR on the CD8, CD4 and B cell compartment in young, control (old) and restricted animals. In these control and restricted cohorts of animals in groups 1, 2 and 3 we will, therefore, determine whether aging can influence the immune response and whether DR can change this.