Brain Bug

Bacterial meningitis is life-threatening. Caused by infection of the brain coverings (meninges) with bacteria, such as E.coli, it's especially deadly in infants. Using mice, researchers investigate how cells in the meninges respond to E.coli infection soon after birth. Upon infection, single nucleus RNA sequencing revealed macrophages, fibroblasts and endothelial cells, which line blood vessels, significantly changed their gene activity. Endothelial cells increased the activity of TLR4, a signalling protein. In mice lacking TLR4, the response to infection was weakened. Next, the team dissected different layers of the meninges – the dura (pictured, top left) and leptomeninges (top right, bottom) – to image cell junction (green, red) and blood-brain barrier proteins (pink). Infection caused proteins normally found at cell junctions in leptomeninges endothelial cells to redistribute elsewhere and leptomeninges capillaries to become disorganised and leaky. This provides insights into how the meninges blood vessel network responds to infection.

Written by Lux Fatimathas

Lux Fatimathas

Writer

Having pursued science through a career in research, communications and publishing, she is currently a writer and editor for a healthcare marketing agency and also juggles freelance science writing.

• Image from work by Jie Wang, Amir Rattner and Jeremy Nathans
• Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
• Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)
• Published in eLife, June 2023