Publication News

The Hedgehog pathway maintains a physiological brain-defense system during neuroinflammation

Co-first authors: Jorge Ivan Alvarez (Postdoctoral Fellow) and Aurore Dodelet-Devillers (Graduated Student)


One of the pathological hallmarks of MS is the inability of the blood-brain-barrier (BBB) to restrict and control the passage of immune cells into the brain. This results in extensive and recurrent central nervous system (CNS) damage that leads to repetitive and  chronic clinical handicap. In an article recently published in Science, a team of researchers led by Dr Alexander Prat and postgraduate fellow Jorge Alvarez at the CHUM Research Centre (CRCHUM) identified mechanisms that promote BBB integrity and  revent the incursion of the immune system into the brain.

In this study, Prat and Alvarez show that astrocytes play a key role in secreting Sonic hedgehog (Shh), a protein that is involved in how the brain is organized, and that endothelial cells express Hh receptors, which together promote proper BBB formation and integrity during embryonic development and adulthood. Using in vitro and in vivo experimental settings, Dr Prat and his team also demonstrated that the Hh pathway plays a critical role in decreasing the adhesion and migration of immune cells into the brain. Thus, the Hh pathway provides a barrier-promoting effect and an endogenous anti-inflammatory balance to CNS-directed immune attacks.

Click Here to view Publication: The Hedgehog Pathway Promotes Blood-Brain Barrier Integrity and CNS Immune Quiescence