CHRONIC VIRAL INFECTIONS--MOLECULAR BIOLOGY OF HUMAN JC VIRUS

我们的研究继续集中在分子之间的相互作用 神经胶质细胞及其嗜神经JC病毒的感染， 在人类大脑的脱髓鞘中，通常在免疫功能低下的 病人 我们目前的结果反映了我们基本方法的基础 完成我们的实验目标 最近我们确定， 由大鼠神经元ID序列和JC病毒共享的基因序列不 在神经胶质细胞中作为转录增强子起类似的作用，JCV是 高度活跃和ID不活跃。 然而，ID序列可以用作 如果将其置于已建立的细胞系中则为增强剂。 JCV序列和ID 序列具有控制转录的顺式作用元件， 对细胞环境的影响。 对JCV DNA的进一步研究显示， 位于复制下游的蛋白质结合位点的必要性 为了使病毒DNA合成发生在细胞中， 反式作用SV40 T蛋白。 在试图识别神经胶质细胞的蛋白质时， 可能与JCV蛋白相互作用的细胞，我们确实发现了一种潜在的 细胞onc基因，p53，这是独立的发育阶段， 人类胎儿脑，但与病毒感染功能无关。 对PML脑组织的进一步研究证实了使用 生物素化的DNA探针，以提供实验室诊断， JCV与PML病变的相关性，并显示出明显的优势 免疫细胞化学检测病毒抗原。 几个新 已经分离出JCV：一个来自诊断为两种疾病的PML患者， 临床上和实验室中使用分子技术和其他 猫头鹰猴的肿瘤 PML病毒分离株显示基因组变化 与野生型JCV相比。 猫头鹰猴JCV分离株使T 蛋白质，其结构不同于其他分离物。 这两 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.