SV40 Pathogenesis of Human Infections

描述（由申请人提供）：有说服力的证据表明，SV40目前正在人类中引起感染。美国医学研究所最近得出结论：“生物学证据表明，在自然条件下，SV40暴露可能导致人类癌症”，并建议“进一步研究SV40在人类中的传播性”。与SV40相关的特定人类肿瘤类型包括非霍奇金淋巴瘤。本提案的目的是评估SV40在人类中的发病机制和传播性，并确定病毒大t抗原（T-ag）羧基(C)末端的可变结构域在病毒发病过程中是否具有重要的功能。具体目的如下：(1)确定SV40感染在目标人群（器官移植受者）中的流行、传播和发病率。我们将对成年移植患者外周血和尿液中SV40的存在进行前瞻性评估。SV40菌株将被表征，并确定病毒基因组在人类组织和恶性肿瘤中的状态和表达。将建立SV40感染与疾病（包括全身性淋巴瘤的发展）之间的临床和病理相关性。(2)确定SV40菌株变异对人外周血单核细胞（PBMCs）病毒复制和b细胞淋巴细胞永生化的影响。将测试不同SV40菌株在pbmc亚群中的复制潜力以及在B淋巴细胞中的永生化能力。病毒DNA在永生化b细胞中的状态和表达将被确定。在受感染的pbmc中，将监测病毒调控区域的变化。(3)鉴定c端T-ag互作细胞蛋白。从人类恶性肿瘤中提取的SV40 T-ag将用于酵母双杂交系统筛选人类淋巴细胞cDNA文库；识别T-ag c端结构域的相互作用蛋白(s)将被表征；将比较与野生型和突变型T-ags的相互作用。该计划解决了我们在人类SV40感染的传播和发病机制方面的重要知识空白。这将揭示SV40菌株对人类的致病作用是否不同，以及c端T-ag结构域在这些过程中可能发挥的作用。这一新信息将有助于更好地理解SV40人类感染的生物学，并可能为SV40参与人类恶性肿瘤的机制提供见解。

DESCRIPTION (provided by applicant): Persuasive evidence now indicates that SV40 is causing infections in the human population today. The Institute of Medicine recently concluded "the biological evidence is of moderate strength that SV40 exposure could lead to cancer in humans under natural conditions" and recommended "further study of the transmissibility of SV40 in humans". Specific human tumor types associated with SV40 include non-Hodgkin's lymphoma. The goals of this proposal are to evaluate the pathogenesis and transmissibility of SV40 in humans and to determine if the variable domain at the carboxy (C) terminus of the viral large T-antigen (T-ag), is functionally important in viral pathogenesis. The specific aims are the following: (1) Determine the prevalence, transmission, and morbidity of SV40 infections in a target human population (organ transplant recipients). We will evaluate prospectively the presence of SV40 in peripheral blood cells and in urine among adult transplant patients. SV40 strains will be characterized and the state and expression of the viral genome in human tissues and malignancies determined. Clinical and pathological correlations will be established between SV40 infections and disease, including the development of systemic lymphomas. (2) Determine the influence of SV40 strain variation on viral replication in human peripheral blood mononuclear cells (PBMCs) and on immortalization of B-cell lymphocytes. Different SV40 strains will be tested for replication potential in subsets of PBMCs and for immortalization ability in B lymphocytes. The state and expression of viral DNA in immortalized B-cells will be determined. Viral regulatory region changes will be monitored in infected PBMCs. (3) Identify C-terminal T-ag interactive cellular proteins. An SV40 T-ag derived from human malignancies will be used to screen a human lymphocyte cDNA library using the yeast two-hybrid system; interactive protein(s) that recognize the C-terminal domain of T-ag will be characterized; interactions with wild-type and mutant T-ags will be compared. This program addresses important gaps in our knowledge concerning the transmission and pathogenesis of SV40 infections in humans. It will reveal if SV40 strains vary in pathogenic effects in humans and the possible role of the C-terminal T-ag domain in those processes. This new information will allow better understanding of the biology of SV40 human infections and may provide insights into the mechanisms of SV40 involvement in human malignancies.