CHRONIC VIRAL INFECTIONS--MOLECULAR BIOLOGY OF HUMAN JC VIRUS

我们的研究继续集中在分子间的相互作用上 神经胶质细胞及其感染嗜神经性JC病毒 在人脑中脱髓鞘，通常在免疫功能受损 有耐心的。我们目前的结果反映了我们基本方法的基础 来完成我们的实验目标。最近我们已经确定， 大鼠神经元ID序列和JC病毒共享的基因序列不同 在神经胶质细胞中的功能类似于转录增强子，JCV是 高度活跃，身份不活跃。然而，ID序列可以用作 一种增强剂，如果放入已建立的细胞系中。JCV序列和ID 序列具有控制转录依赖的顺式作用元件 在蜂窝环境上。对JCV DNA的进一步研究揭示了 位于复制下游的蛋白质结合部位的必要性 病毒DNA合成的起源是为了在细胞中产生 反式SV40T蛋白。为了鉴定神经胶质细胞的蛋白质 可能与JCV蛋白相互作用的细胞，我们确实发现了潜在的 细胞癌基因p53，它不受发育阶段的影响 人胎脑，但在功能上与病毒感染无关。 对PML脑组织的进一步研究证实了使用PML的准确性 生物素化DNA探针提供实验室诊断 JCV与PML病变的相关性并显示出明显的优势 过度使用免疫细胞化学检测病毒抗原。几个新的 已分离出JCV：其中一例来自一名PML患者，诊断为两者都有 在临床和实验室中使用分子技术和其他 来自猫头鹰猴子的肿瘤。PML病毒分离株出现基因组变化 与野生型JCV进行比较。猫头鹰猴JCV分离物产生了T 在结构上与其他分离株不同的蛋白质。这两个都是 新的JCV毒株提供了该病毒基因改变的证据。

Our studies have continued to focus on the molecular interactions between glial cells and their infection with neurotropic JC virus which culminates in demyelination in the human brain, usually in the immunocompromised patient. Our current results reflect the foundation of our basic approach in accomplishing our experimental goals. Recently we have determined that gene sequences shared by a rat neuronal ID sequence and the JC virus do not function similarly as transcription enhancers in glial cells, JCV being highly active and ID inactive. The ID sequence, however, can function as an enhancer if placed in established cell lines. Both JCV sequences and ID sequence have cis acting elements which control transcription depending upon the cellular environment. Further study of the JCV DNA revealed a necessity of a protein binding site located downstream of the replication origin in order for viral DNA synthesis to occur in cells which produce a trans acting SV40 T protein. In attempts to identify proteins of glial cells which may interact with the JCV protein, we did find a potential cellular onc gene, p53, which is made independent of developmental stage in human fetal brain but not functionally associated with viral infection. Further studies of PML brain tissue confirmed the accuracy of using biotinylated DNA probes to provide a laboratory diagnosis of the association of JCV and lesions of PML and showed a significant advantage over using immunocytochemical detection of viral antigen. Several new isolations of JCV have been made: one from a PML patient diagnosed both clinically and in the laboratory using molecular techniques and the other from an owl monkey tumor. The PML virus isolate showed genomic changes compared with the wild type JCV. The owl monkey JCV isolate made a T protein which is structurally different from other isolates. Both of these new JCV strains provide evidence of genetic alteration of this virus.