OBJECTIVE To describe the diagnosis and management of a 49-year-old woman with multiple sclerosis (MS) developing a progressive hemiparesis and expanding MRI lesion suspicious of progressive multifocal leukoencephalopathy (PML) 19 months after starting natalizumab. RESULTS Polyomavirus JC (JCV)-specific qPCR in CSF was repeatedly negative, but JCV-specific antibodies indicated intrathecal pro...

Genomic sequences of the human polyomaviruses, JC virus (JCV) and BK virus (BKV), and simian virus 40 (SV40) have been reported from several types of human brain tumors, but there have been no population-based seroepidemiologic studies to evaluate the association between polyomavirus infection and brain tumors. We conducted a case-control study, nested within a prospective cohort, to investigat...

BACKGROUND Propagation of poliovirus in monkey kidney cells led to the inadvertent contamination of poliovirus vaccines with simian virus 40 (SV40) between 1955 and 1963. Recent studies using polymerase chain reaction-based strategies have detected SV40 DNA in a large number of tumor types. The finding of SV40 DNA in tumors from individuals who are too young to have been exposed to SV40-contami...

Progressive multifocal leukoencephalopathy (PML) is a lytic infection of the central nervous system caused by the reactivation of John Cunningham Virus (JCV) in severely immunosuppressed patients. Occurrence of PML after solid organ transplantations, especially after liver transplantation, is rare. If a patient has poor prognostic factors such as atypical radiological involvements or high viral...

The effectiveness of nucleoside analogs in blocking viral multiplication was evaluated using an immortalized human neuroglial cell line capable of sustaining a persistent JCV infection, SVG-JC. Results from in situ DNA hybridization and hemagglutination assays performed on drug treated cultures were used as a measure of viral DNA replication and multiplication, respectively. Of the three drugs ...

Natalizumab is currently one of the best options for treatment of patients with Multiple Sclerosis who have failed traditional prior therapies. However, prolonged use, prior immunosuppressive therapy and anti-JCV antibody status have been associated with increased risk of developing progressive multifocal leukoencephalopathy (PML). The evaluation of these conditions has been used to estimate ri...

The complete genomes of three new Type 1 strains of JC virus (JCV) from urine have been analysed. These were subtype 1A, subtype 1B and Type 4 as assigned from a short typing fragment in the VP1 gene. They differ from Mad1 (subtype 1A) by less than 1.0% of the DNA sequence. Based on its complete genome, the JCV Type 4 strain falls into a Type 1 subgroup. Type 4, with several Type 3-like sites i...

JC virus (JCV) is a polyoma virus that commonly infects humans. We have found T antigen DNA sequences of JCV in the mucosa of normal human colons, colorectal cancers, colorectal cancer xenografts raised in nude mice, and in the human colon cancer cell line SW480. A larger number of viral copies is present in cancer cells than in non-neoplastic colon cells, and sequence microheterogeneity occurs...

We collected blood-fed, snow-melt mosquitoes (Culicidae: Culiseta and Aedes) to describe the feeding patterns of potential mosquito vectors of Jamestown Canyon virus (JCV, Bunyaviridae: Orthobunyavirus). JCV is an arthropod-borne, zoonotic virus with deer as the primary amplifying host in western alpine ecosystems. We collected mosquitoes from natural resting areas, fiber pots, and carbon-dioxi...

This study evaluated the relative occurrences of BK virus (BKV) and JC virus (JCV) infections in patients with chronic kidney disease (CKD). Urine samples were analysed from CKD patients and from 99 patients without CKD as a control. A total of 100 urine samples were analysed from the experimental (CKD patients) group and 99 from the control group. Following DNA extraction, polymerase chain rea...