Poliovirus Induces Apoptosis in the Mouse Central Nervous System

JOURNAL OF VIROLOGY, 1999 · DOI: · Published: July 1, 1999

Simple Explanation

Poliovirus (PV) is the cause of paralytic poliomyelitis, resulting from the destruction of motoneurons due to PV replication. The study investigates if PV-induced central nervous system (CNS) injury is linked to apoptosis using mice. The study used transgenic mice expressing the human PV receptor, infected intracerebrally with neurovirulent PV-1 Mahoney strain or a paralytogenic dose of the attenuated PV-1 Sabin strain. The study found DNA fragmentation in CNS tissue from paralyzed mice, viral antigens and DNA fragmentation colocalized in neurons, and morphological changes characteristic of apoptosis in motoneurons.

Study Duration

5 Days

Participants

Transgenic and non-transgenic mice

Evidence Level

Not specified

Key Findings

1
PV infection causes cleavage of DNA into nucleosomes in the mouse CNS, indicating apoptosis.
2
Apoptosis, as detected by ELISA, coincided with maximal virus growth in the spinal cord and brain stem and with the onset of paralysis.
3
The attenuated PV-1 Sabin strain can kill cells of the CNS by an apoptotic process, similar to the neurovirulent strain of PV-1.

Research Summary

This study demonstrates that poliovirus (PV) infection in mice leads to apoptosis in the central nervous system (CNS), contributing to the paralysis observed in poliomyelitis. Both neurovirulent and attenuated strains of PV can induce apoptosis in the CNS, with the extent of apoptosis correlating with viral replication levels. Apoptosis occurs not only in infected neurons but also in neighboring uninfected cells, suggesting both direct and indirect mechanisms of cell death contribute to CNS injury.

Practical Implications

Understanding Poliovirus Pathogenesis

The study provides insights into the mechanisms by which poliovirus causes damage to the central nervous system, specifically highlighting the role of apoptosis.

Developing Targeted Therapies

Identifying apoptosis as a key factor in poliovirus-induced paralysis could lead to the development of therapeutic strategies aimed at modulating or preventing apoptosis to reduce neuronal damage.

Improving Vaccine Strategies

The findings suggest that even attenuated poliovirus strains can induce apoptosis under certain conditions, which may have implications for the development and use of poliovirus vaccines.

Study Limitations

1
The study is limited by the use of a mouse model, which may not fully replicate the pathogenesis of poliomyelitis in humans.
2
The mechanisms by which PV induces apoptosis in non-neuronal cells require further investigation.
3
The study does not address the potential for long-term effects of PV-induced apoptosis in the CNS.

Your Feedback

Was this summary helpful?

Back to Immunology