First published online November 8, 2006
Journal of Cell Science 119, 2201e (2006)
© The Company of Biologists Limited
Prion protein mans the barrier
Prion diseases such as Creutzfeld-Jacob disease involve the conversion of prion protein (PrPC) to its pathogenic isoform PrPSc. PrPC a glycosylphosphatidylinositol-anchored protein is highly expressed in brain and several other tissues, but its physiological function is unclear. Now, Sylvie Cazaubon and co-authors report that PrPC localizes to intercellular junctions between brain endothelial cells and regulates the trans-endothelial migration of immune cells (see p. 4632). Brain endothelial cells form the blood-brain barrier, which stops circulating immune cells and pathogens entering the brain. The authors show that PrPC is expressed by vascular endothelium in the brain and is present in lipid raft microdomains at endothelial cell-cell junctions in brain endothelial cells from several species. This localization, they report, probably depends on homophilic interactions between PrPC molecules on adjacent cells. They also reveal that antibodies to PrPC block the migration of monocytes through human brain endothelial cells in vitro. Thus, the authors conclude, a previously unsuspected physiological role for PrPC could be to modulate immune responses in the brain by controlling monocyte entry.
Related articles in JCS:
- Tyrosine phosphorylation of p145met mediated by EGFR and Src is required for serum-independent survival of human bladder carcinoma cells
- Natsumi Yamamoto, Gunay Mammadova, Robert X.-D. Song, Yasuo Fukami, and Ken-ichi Sato
JCS 2006 119: 4623-4633.
[Abstract]
[Full Text]