Brain Cells May Attack Immune System

U.S. researchers say they have discovered brain cells called astrocytes radically change their shape and function after contact with anti-viral T-cells.

Astrocytes are normally star-shaped cells that provide nutrients to other types of brain cells, help form the blood-brain-barrier and control brain cell activity, the scientists said. But research conducted by scientists from the Board of Governors Gene Therapeutics Research Institute at Cedars-Sinai Medical Center shows when T cells attack an astrocyte infected with a virus, the projecting tentacles of the astrocyte withdraw and the cell changes to display a single, major protrusion extending toward the immune system’s T-cell.

The researchers say the new data suggest the astrocyte might be defending itself by engulfing the attacking T cells.

"Further studies into the cellular and molecular processes leading to these changes could have implications for understanding and treating brain infections, brain tumors and neurodegenerative disorders," said Dr. Pedro Lowenstein, director of the research institute and senior author of study.

The researchers said their findings could influence the treatment of AIDS, West Nile virus and other viral infections, brain cancer and autoimmune diseases.

The study appears in the online journal PLoS One.