EPSTEIN BARR VIRUS LATENCY

爱泼斯坦-巴尔病毒是一种人类疱疹病毒，可潜伏感染和 体外永生化人B淋巴细胞。这种病毒在中国持续了一生 在体内，并可在免疫抑制的个体中引起淋巴瘤。 尽管在体外对感染和潜伏期进行了广泛的研究， 对体内的潜伏感染知之甚少。这项建议的目的是 是描述体内EB病毒潜伏感染的特征以及如何 这种潜伏期受到免疫抑制的干扰。 我们已经开发出一种高度敏感的EBV DNA聚合酶链式反应检测方法，它可以 美国将在多达5x10/7的未感染细胞中检测单个基因组。我们 已经使用这种检测方法来测量病毒感染细胞的频率 健康个体的外周血液，并证明 这些细胞的表型(CD23-B细胞)与 在体外，EBV感染的淋巴母细胞。我们打算进一步刻画 细胞的表面表型(激活的与静止的、记忆 VS处女，成熟VS BL/生发中心样，BI VS B2)。这 信息将识别体内EB病毒潜伏期的靶细胞(S)，并 用于制定协议，以丰富携带有 病毒，然后可以使用RNA聚合酶链式反应检测病毒基因的表达。 我们假设健康个体中的感染细胞将是 休息并表达一组有限的潜在基因，以避免 免疫监控。在免疫抑制时，这些细胞的频率 然而，不应该改变类似于典型EBV淋巴母细胞的细胞， 通常处于免疫监视和潜在的前驱体 免疫母细胞性淋巴瘤，现在将被检测到。这些研究将是 与新医院的移植股合作进行 英格兰医疗中心的长期目标是发现潜力 发生EBV淋巴瘤的免疫抑制患者的危险因素。

Epstein-Barr virus is a human herpesvirus that can latently infect and immortalize human B lymphocytes in vitro. The virus persists for life in vivo and can give rise to lymphoma in immunosuppressed individuals. Although infection and latency have been studied extensively in vitro, little is known about latent infection in vivo. The aim of this proposal is to characterize latent infection by Epstein-Barr virus in vivo and how that latency is perturbed by immunosuppression. We have developed a highly sensitive DNA PCR assay for EBV which allows us to detect a single genome in as many as 5x10/7 uninfected cells. We have used this assay to measure the frequency of virus infected cells in the peripheral blood of healthy individuals and to demonstrate that the phenotype of these cells is uniquely different (CD23- B cells) from that of in vitro, EBV infected lymphoblasts. We intend to further characterize the cell surface phenotype of the cells (activated vs. resting, memory vs. virgin, mature vs. BL/germinal center like, Bi vs. B2). This information will identify target cell(s) for EBV latency in vivo and be used to develop protocols for enriching cell populations that carry the virus, which can then be tested for viral gene expression using RNA PCR. We hypothesize that the infected cells in healthy individuals will be resting and expressing a limited set of latent genes, so as to avoid immunosurveillance. Upon immunosuppression the frequency of these cells should not change, however, cells resembling typical EBV lymphoblasts, normally under immunosurveillance and potential precursors for immunoblastic lymphoma, will now be detected. These studies will be carried out in collaboration with the transplantation unit at the New England Medical Center with the long term goal of identifying potential risk factors in immunosuppressed patients who develop EBV lymphoma.