Pathogenesis of progressive multifocal leukoencephalopathy--revisited
Martyn K White1, Kamel Khalili
1Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA.
The Journal of Infectious Diseases
|January 14, 2011
Summary
Progressive multifocal leukoencephalopathy (PML) is a rare brain disease caused by the JC virus. This review examines unclear aspects of PML pathogenesis, including viral latency and reactivation in immunosuppressed individuals.
Area of Science:
- Neurovirology
- Immunology
- Central Nervous System Disorders
Background:
- Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the central nervous system.
- The JC virus, the etiological agent of PML, is widespread in the human population.
- PML is often associated with immunosuppression, including HIV/AIDS and immunomodulatory drug use.
Purpose of the Study:
- To review and examine the current understanding of PML pathogenesis.
- To address critical unanswered questions regarding JC virus latency, reactivation, and transmission.
Main Methods:
- This is a review article, synthesizing existing scientific literature and evidence.
- It revisits established hypotheses and examines available data on PML pathogenesis.
Main Results:
- JC virus is ubiquitous, but PML is rare, suggesting a critical role for host immune status.
- A widely accepted hypothesis posits childhood primary infection, latency, and reactivation under immunosuppression.
- Key aspects of PML pathogenesis, including latency mechanisms, sites, viral variants, and transmission, remain unclear.
Conclusions:
- Understanding the molecular basis of JC virus latency and reactivation is crucial for comprehending PML development.
- Further research is needed to elucidate the complete lifecycle of JC virus and its transmission routes.
- Clarifying these aspects is essential for developing effective strategies to prevent and treat PML.
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