CHRONIC VIRAL INFECTIONS--MOLECULAR BIOLOGY OF HUMAN JC VIRUS

我们继续研究JC病毒和人类神经胶质细胞的分子病理学， 细胞培养，最近，与人脑组织切片， 患有进行性多灶性白质脑病（PML）的感染患者。 实验的重点是在细胞内水平描述的性质， 病毒在CNS中持续存在，PML的发病机制为脱髓鞘 疾病，以及病毒和细胞的一般调节机制， 基因参与。 我们的成果包括解决最大的问题， 与JC合作提出，即宿主和组织限制， 在培养物中生长至原代人胎儿神经胶质细胞。 我们已经建立了 使用突变体的人胎儿星形胶质细胞的永生化系 SV40转化基因。 这些细胞能够产生感染性JCV 并使我们能够检查CV DNA复制的动力学和T 蛋白质合成 我们还发现，SV40 T蛋白在 人神经胶质细胞与神经胶质细胞蛋白p53复合并稳定 细胞中的这种蛋白质。 JCV T蛋白似乎不与 与p53蛋白，也许是由于确认之间的差异， SV40和JCV的T蛋白。 这种差异的其他证据来自 从我们的实验表明，烷基化的半胱氨酸残基的JCV T蛋白是必需的，以解决免疫沉淀的T 蛋白质的变性凝胶电泳。 这是没有必要的， SV40的T蛋白或相关的人BK病毒。 研究 石蜡包埋或冷冻的PML患者脑组织显示， 使用原位杂交检测JCV DNA的存在，并与 使用免疫细胞化学试验检测病毒衣壳抗原。 这些 研究还表明，少突胶质细胞是 PML斑块中JCV基因表达但存在奇异星形胶质细胞 显示JCV DNA和衣壳抗原。 后一个发现问题的作用 JC病毒在恶性胶质瘤发病中的作用 这是其他人建议的一般人群。

Our studies continue on the molecular pathology of JC virus and human glial cells in culture, and more recently, with human brain tissue sections from infected patients wth progressive multifocal leukoencephalopathy (PML). Experiments have focues at the intracellular level describing the nature of viral persistance in the CNS, pathogenesis of PML as a demyelinating disease, and the mechanisms of generic regulation of the viral and cellular genes involved. Our results include solving the biggest problems that working with JC has presented, namely the host and tissue restriction for growth to primary human fetal glial cells in culture. We have estalbished an immortalized line of human fetal astroglial cells using a mutant transforming gene of SV40. These cells are able to produce infectious JCV and have allowed us to examine the kinetics of CV DNA replication and T protein synthesis. We have also found that the SV40 T protein made in human glial cells complexes with a glial cell protein, p53, and stablizes this protein in the cell. The JCV T protein does not appear to complex with the p53 protein, perhaps due to confirmational differences between the T proteins of SV40 and JCV. Additional evidence for such differences came from our experiments suggesting alkylation of cycteine residues of the JCV T protein was necessary in order to resolve the immunoprecipitated T protein using denaturing gel electrophoresis. This was not necessary for either the T proteins of SV40 or the related human BK virus. Studies of paraffin embedded or fozen brain tissue from PML patients showed the presence of JCV DNA using in situ hyridization and correlated with the detection of viral capsid antigen using immunocytochemical tests. These studies also revealed that aligodendroglian cells are the main target for JCV gene expression but that bizarre astrocyctes present in PML plaques showed JCV DNA and capsid antigen. This latter finding questions role the of JC virus may have in the pathogenesis of malignant gliomas in the general population that has been suggested by others.