Related Experiment Video

Updated: Aug 5, 2026

Isolation of Brain-infiltrating Leukocytes
06:44

Isolation of Brain-infiltrating Leukocytes

Published on: June 13, 2011

19.9K

JC Polyomavirus Abundance and Distribution in Progressive Multifocal Leukoencephalopathy (PML) Brain Tissue

Keith A Wharton1, Catherine Quigley1, Marian Themeles1

  • 1Translational Pathology Laboratory, Biogen Inc., Cambridge, MA, United States of America.

Plos One
|May 19, 2016
PubMed

Insights

JC polyomavirus (JCV) can cause progressive multifocal leukoencephalopathy (PML). This study found JCV spreads along myelin sheaths, potentially explaining axonal destruction in PML patients.

Area of Science:

  • Neurovirology
  • Immunology
  • Neuropathology

Background:

  • JC polyomavirus (JCV) infection is common, but progressive multifocal leukoencephalopathy (PML) is rare, typically in immunosuppressed individuals.
  • PML is an emerging drug safety concern linked to immunomodulatory therapies, including efalizumab.

Purpose of the Study:

  • To investigate the relationship between JCV life cycle and PML pathology.
  • To analyze viral evolution and spread in PML brain tissue from an efalizumab-treated patient.

Main Methods:

  • Histopathology and quantitative genomic, proteomic, and molecular localization analyses of autopsy brain tissue.
  • Sequence analysis of regulatory DNA, VP1, VP2, and agnoprotein in lesional brain tissue.

Main Results:

  • Identified PML-associated mutations in JCV regulatory DNA, VP1, and agnoprotein, plus novel VP2 mutations, indicating viral evolution.
  • Observed a strong correlation between demyelination, axonal destruction, and JCV dispersion along white matter myelin sheaths.
  • Findings were consistent with a similar case in an immunocompromised rhesus macaque.

Conclusions:

  • JCV undergoes significant evolution within PML lesions.
  • Long-range spread of JCV and axonal destruction in PML may involve extracellular association with the white matter myelin sheath.

More Related Videos

Merkel Cell Polyomavirus Infection and Detection13:45

Merkel Cell Polyomavirus Infection and Detection

Published on: February 7, 2019

10.5K
Measurement of BK-polyomavirus Non-Coding Control Region Driven Transcriptional Activity Via Flow Cytometry11:54

Measurement of BK-polyomavirus Non-Coding Control Region Driven Transcriptional Activity Via Flow Cytometry

Published on: July 13, 2019

9.4K

Related Concept Videos

Viral Meningitis01:18

Viral Meningitis

Viral meningitis is the most common form of meningitis and is often referred to as aseptic meningitis to indicate the absence of bacterial involvement. It is generally milder than bacterial meningitis, with symptoms including fever, headache, stiff neck, drowsiness, nausea, photophobia, and vomiting. Rarely, more severe manifestations or death may occur. Common causative agents include enteroviruses, particularly coxsackie A and B viruses and echoviruses, all members of the Enterovirus genus...
Poliomyelitis01:17

Poliomyelitis

Poliomyelitis is caused by poliovirus, a small, non-enveloped, positive-sense RNA virus of the Picornaviridae family and Enterovirus genus. Transmission occurs primarily via the fecal-oral route, often through ingestion of contaminated water or food. The virus initially replicates in the oropharynx and intestinal mucosa, particularly in lymphoid tissues such as the tonsils, Peyer’s patches, and regional lymph nodes. Primary viremia follows, allowing dissemination throughout the body.In most...
Arboviral Encephalitis01:25

Arboviral Encephalitis

Arboviral encephalitis refers to brain inflammation caused by arthropod-borne viruses, particularly those transmitted through mosquito vectors. Among these, West Nile virus (WNV), a member of the Flaviviridae family, is a significant public health concern. WNV is an enveloped, positive-sense, single-stranded RNA virus. Human infection typically begins when an infected mosquito introduces the virus into the dermis during feeding. The primary transmission cycle involves birds as amplifying hosts...
Cytomegalovirus Disease01:27

Cytomegalovirus Disease

Cytomegalovirus (CMV) disease is caused by human cytomegalovirus, a double-stranded DNA virus of the Herpesviridae family. While primary CMV infection is often asymptomatic in immunocompetent individuals, the virus can cause severe disease in neonates and immunocompromised patients. CMV is the most common cause of congenital viral infection in the United States, and a major pathogen in solid organ and hematopoietic stem cell transplant recipients.CMV is transmitted via bodily fluids, sexual...
Encephalitis l: Introduction01:19

Encephalitis l: Introduction

Encephalitis is inflammation of the brain parenchyma, most often due to infections or autoimmune processes. It presents with neuropsychiatric features such as fever, altered mental status, behavioral changes, cognitive dysfunction, seizures, focal deficits, and sometimes autonomic instability. In some cases, the meninges are also involved, resulting in meningoencephalitis.Infectious CausesInfectious encephalitis is most commonly viral but can also result from bacterial, fungal, or parasitic...
Encephalitis ll: Pathophysiology01:26

Encephalitis ll: Pathophysiology

Encephalitis is inflammation of the brain parenchyma caused by direct viral invasion or immune-mediated mechanisms triggered by infections or tumors. Both processes lead to neuronal injury, disrupted neurotransmission, and diverse neurological symptoms, often with overlapping clinical and pathological features.Autoimmune EncephalitisIn autoimmune encephalitis, antibodies target neuronal antigens on cell surfaces, synapses, or within neurons. A key example is anti-NMDAR encephalitis, which can...