Viruses on the Brain

Viral infections of the central nervous system may trigger cytokines that induce seizures.

By | May 1, 2013


DISSECTING SEIZURES: Mice that suffer seizures after viral infection have a greater number of macrophages (green) in the brain.COURTESY OF ROBERT FUJINAMThe paper
M.F. Cusick et al., “Infiltrating macrophages are key to the development of seizures following virus infection,” J Virol, 87:1849-60, 2013.

The matter
Of the approximately 2.2 million Americans affected by epilepsy, a third do not respond to current antiseizure treatments, and nearly three quarters of all cases have unknown causes. Though scientists have previously linked more than 100 species of viruses that infect the central nervous system (CNS) to patients suffering from recurring seizures, the significance of viral infections in epilepsy is still unclear.

The model
Researchers at the University of Utah School of Medicine, led by Robert Fujinami, had previously developed a mouse model that suffered from seizures after infection with a CNS-targeting virus. Though the mice could clear the infection, they often continued to have seizures. To dissect how the virus might spark recurring seizures during and long after infection, Fujinami and his team took a close look at the immune responses.

The match
Fujinami’s team found that during a viral brain infection, infiltrating macrophages produce high levels of a cytokine called interleukin 6 (IL-6), which, among other cytokines, had previously been linked to seizures in the mice. To understand the importance of these IL-6–spewing macrophages, the team used a drug to block them from the CNS, which resulted in the mice having fewer seizures. Though it’s still unclear how the virus triggers seizures after the infection, Fujinami and his team suspect that macrophages continue to swarm the CNS.

The aftermath
The results suggest that “the side effect of this powerful immune response is a disruption in brain function and the ensuing brain seizures,” says Thomas M. Petro of the University of Nebraska Medical Center, who was not involved in the study.


Add a Comment

Avatar of: You



Sign In with your LabX Media Group Passport to leave a comment

Not a member? Register Now!

LabX Media Group Passport Logo

Popular Now

  1. Sex Differences in the Brain
    Features Sex Differences in the Brain

    How male and female brains diverge is a hotly debated topic, but the study of model organisms points to differences that cannot be ignored.

  2. Brain Gain
    Features Brain Gain

    Young neurons in the adult human brain are likely critical to its function.

  3. DNA Repair Pioneers Win Nobel
    Daily News DNA Repair Pioneers Win Nobel

    Tomas Lindahl, Paul Modrich, and Aziz Sancar have won this year’s Nobel Prize in Chemistry for their work elucidating mechanisms of DNA repair.

  4. Antiparasite Drug Developers Win Nobel
    Daily News Antiparasite Drug Developers Win Nobel

    William Campbell, Satoshi Omura, and Youyou Tu have won this year’s Nobel Prize in Physiology or Medicine in recognition of their contributions to antiparasitic drug development.

Logos Biosystems
Logos Biosystems
Life Technologies