WASHINGTON, Sept. 3 (UPI) -- A new study sheds light on the disease bacterial meningitis, an often deadly swelling of the brain from bacterial infection.
Scientists at the University of California-San Diego discovered how strep bacteria are able to penetrate the defensive membrane -- called the "blood-brain" barrier -- around the brain, and how the resulting infection provoked acute swelling.
"We believe our ongoing studies ... will help uncover basic biologic principles that will lead to improved therapies for meningitis and other central nervous system infections," said lead author Kelly Doran.
The researchers showed how infection by Group B Streptococcus -- the leading cause of bacterial meningitis in human infants -- ordinarily triggers an aggressive counterattack by the body's immune system.
But in cases where meningitis develops, the researchers found that a capsule-like coating around the bacteria helps camouflage it, foiling immune detection.
Then, as concentrations of bacteria around the brain rise, a bacterial toxin degrades the cells of the blood-brain barrier. This provokes an extreme immune response, flooding the area in and around the brain with white blood cells. But it's too late. The amount of white cells added to inflammation from the bacteria causes unnatural swelling, and, at worst, death.
