Choroid Plexus Epithelial Cells is an important cell type in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Choroid plexus epithelial cells (CPECs) are specialized ependymal cells that form the blood-cerebrospinal fluid barrier (BCSFB) and produce cerebrospinal fluid. They represent a critical interface between the peripheral circulation and the central nervous system.
| Property |
Value |
| Location |
Choroid plexus (lateral, third, fourth ventricles) |
| Marker Genes |
TTR (transthyretin), AQP1 (aquaporin 1), KCNQ1, SLC12A2 (NKCC1) |
| Developmental Origin |
Neuroectoderm, roof plate |
| Key Functions |
CSF production, BCSFB, molecular filtration |
The choroid plexus consists of:
- Epithelial cells: Cuboidal cells with microvilli and cilia
- Capillary endothelium: Fenestrated capillaries
- Stromal tissue: Connective tissue core
Unlike the BBB, the BCSFB has:
- Tight junctions between epithelial cells
- Fenestrated capillaries (leaky)
- Epithelial barrier is the main constraint
- High mitochondrial density for active transport
CPECs produce CSF via:
- Active transport: Ion pumps (Na+/K+ ATPase, NKCC1)
- Aquaporin 1: Water transport
- Secretory vesicles: Protein and peptide secretion
- Daily production: ~500 mL/day in adults
- Tight junctions restrict paracellular flow
- Selective transporters allow essential molecules
- Efflux pumps remove waste products
- Drug permeability differs from BBB
CPECs express:
- Transthyretin (TTR): T4 transport
- Transferrin receptor: Iron transport
- Organic anion transporters: Drug clearance
- Various channels: Ion homeostasis
Choroid plexus changes in AD:
- CSF secretion decline: Reduced production with age/disease
- Barrier dysfunction: Increased permeability
- Amyloid clearance: CPECs participate in Aβ clearance via LRP2
- Tau transport: May release tau into CSF
- Atrophy: Choroid plexus volume changes
- CSF composition changes: Altered protein content
- Barrier dysfunction: Increased permeability
- Iron regulation: Altered iron handling
- CSF hypersecretion: Sometimes observed
- Barrier changes: Altered BCSFB permeability
- Immune cell trafficking: Potential entry point
- Impaired CSF dynamics: Absorption rather than production issue
- Choroid plexus function: Often normal in NPH
- Transthyretin: Decreased in AD
- Apolipoprotein J: Changed in neurodegeneration
- Secreted factors: Reflect choroid plexus health
- Choroid plexus volume: Enlarged in some conditions
- Signal changes: On MRI reflect dysfunction
- Choroid plexus as alternative delivery route
- Targeting CPECs for CNS drug delivery
- BCSFB modulation for therapy
- Protecting choroid plexus function
- Enhancing CSF production when deficient
- Repairing BCSFB damage
The study of Choroid Plexus Epithelial Cells has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
- Strazielle & Ghersi-Egea, Physiology of blood-brain interfaces in relation to brain disposition of drug (2013)
- Serot et al., Choroid plexus, aging, and Alzheimer's disease (2012)
- Marques et al., The choroid plexus as a pathogenic doorway in sporadic Parkinson's disease (2017)