Navigation Links
New insights into how brain responds to viral infection
Date:3/31/2009

March 31, 2009, New York, NYScientists at Columbia University Mailman School of Public Health have discovered that astrocytes, supportive cells in the brain that are not derived from an immune cell lineage, respond to a molecule that mimics a viral infection using cellular machinery similar to that used by classical immune cells in the blood. While scientists have been aware of the capacity of astrocytes to trigger an innate immune response when encountering a foreign agent, this work provides a new understanding of the complex mechanisms responsible for induction and regulation of inflammation in the brain and has significant implications for both the diagnosis and treatment of brain infections. The study is published as the cover article in the April 2009 issue of The FASEB Journal (http://www.fasebj.org).

In the course of trying to contain and neutralize a virus that has breached the protective barrier of the central nervous system, immune mediators secreted by astrocytes may injure other cells and tissues in the vicinity and cause additional life-threatening inflammation.

By defining the nature of inflammatory responses by brain astrocytes, this study has implications for both the diagnosis of chronic infections of the central nervous system, as well as the treatment of acute and chronic brain infections. Viral infections of the brain are associated with extremely high morbidity and mortality; in most cases, the specific microbial cause is unknown. Even when a viral cause is clear, the specific antiviral tools at our disposal remain limited. This work provides a means for implementation of a more general therapeutic approach to viral brain infections that may be effective across a wide range of viruses, or even where a virus is suspected but the offending agent cannot be identified.

"Studies such as this take us one step closer to understanding both the risk and benefit associated with antiviral immune response and may lead to new treatment strategies," said W. Ian Lipkin, MD, senior author of the paper, director of the Mailman School of Public Health's Center for Infection and Immunity, John Snow Professor of Epidemiology, and professor of Neurology and Pathology.

The researchers compared two methods of exposing a cell to this virus-like challengeone from outside the cell and the other by direct delivery into the cell's cytoplasm. By culturing the supportive cells known as astrocytes obtained from the brains of newborn mice and exposing them to a virus-like molecule (called Poly I:C) from the outside and the inside, the scientists were able to show for the first time the differences between extracellular and intracellular immune response in these supportive brain cells.

Depending on whether the virus-like challenge was introduced extracellularly or intracellularly, the astrocytes produced different levels of inflammatory mediators (cytokines). The researchers were also able to show that a sensor protein known as MDA-5 is critical for astrocytes to be able to recognize viral molecules appearing in a cell's cytoplasm, and when astrocytes were engineered to express dysfunctional MDA-5, this immune response was selectively blocked.

"These findings create an opportunity for targeted design of drugs that may help to curb infection-induced brain inflammation and restrict the extent of damage," said Joari De Miranda, MD, PhD, lead author of the paper and postdoctoral research scientist at the Mailman School of Public Health's Center for Infection and Immunity.

There are a number of diseases that this work can impact in terms of diagnosis and treatment: viral encephalitis; brain disorders associated with congenital viral infections; and neurological or neurodevelopmental disorders suspected of having an immune or inflammatory trigger, such as schizophrenia and autism. There also may be broader implications for the treatment of a wide range of immune-mediated neurologic diseases, such as multiple sclerosis and Parkinson's disease.


'/>"/>

Contact: Randee Sacks Levine
rs363@columbia.edu
212-305-8044
Columbia University's Mailman School of Public Health
Source:Eurekalert

Related medicine news :

1. Insights Give New Hope Against Cystic Fibrosis
2. New Research Released at Annual Society for Adolescent Medicine Meeting Provides Vital Insights into Adolescent Health Issues
3. United Spinal Association Report Reveals the Importance of Studying Multiple Sclerosis in Children: Developing New Insights into MS in Adults
4. Recovery Audit Contractor HealthDataInsights Licenses Milliman Care Guidelines(R)
5. New insights into growth factors role in brain development
6. Gene Insights May Improve Psoriasis Care
7. Researchers Gain Insights Into Aging in Mice
8. Analog Devices Healthcare Team Participates in MIT Forum on Medical Device Industry : ADI's healthcare technology experts Patrick O'Doherty and Tom O'Dwyer offer insights on trends impacting next-generation medical electronic systems.
9. HIV Vaccine Failure Still Brings Insights
10. Genetic Research Offers Insights Into Form of Malaria
11. New insights could lead to a better pneumococcal vaccine
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/7/2016)... , ... December 07, 2016 , ... One of two ... of the securement tape is painful for her. "This is why the co-inventor and ... heads," she said. , They then created a prototype of the patent-pending AV-AIR, a ...
(Date:12/7/2016)... ... OCTOBER XX, 2016 (PRWEB) (PRWEB) December 07, ... ... mystery. A new study entitled “Canine Filamentous Dermatitis Associated with Borrelia Infection” ... in dogs. The study was published in the prestigious Journal of Veterinary Science ...
(Date:12/7/2016)... , ... December 07, 2016 , ... Facial plastic surgeon, ... holiday season by donating a portion of proceeds to two local organizations: North Chicago ... Animal Control & Friends is a team of authorized and trained volunteers who ...
(Date:12/7/2016)... Dallas, TX (PRWEB) , ... December 07, 2016 ... ... a 2016 Top 20 Marketing Campaign Winner in the Folio: Marketing Awards competition. ... Awards recognize the year’s best in pioneering, inventive, and ultimately successful projects undertaken ...
(Date:12/7/2016)... ... December 07, 2016 , ... Gensuite is ... Awards under the Best New Product Launch category. Gensuite’s entry on their EZ ... , BOC Global Events & Training Group is a professional event and training ...
Breaking Medicine News(10 mins):
(Date:12/7/2016)... SAN DIEGO , Dec. 7, 2016   ... today announced that it has completed enrollment in the ... IP receptor agonist targeting the prostacyclin pathway for the ... approximately 60 patients at sites globally. "This ... and is evidence of our strategic focus on our ...
(Date:12/7/2016)... Dec. 7, 2016 Diplomat Pharmacy, Inc. (NYSE: DPLO) has ... Homecare Federation, At-Home IV Infusion Professional, BioRx, MedPro Rx, and XAS ... services, visit diplomat.is/specialty-infusion .  ... Diplomat Specialty Pharmacy (PRNewsFoto/Diplomat Pharmacy, Inc.) ... "As we continue to build on the ...
(Date:12/7/2016)... Kan. , Dec. 7, 2016   Rx Savings ... West Virginia and its Public Employees Insurance Agency ... members access to their innovative healthcare software, ultimately saving money ... with PEIA and provide its members with access to our ... or a more effective, affordable therapy can be found," says ...
Breaking Medicine Technology: