Journal article

The blood-CSF barrier explained: When development is not immaturity

Pia A Johansson, Katarzyna M Dziegielewska, Shane A Liddelow, Norman R Saunders

BIOESSAYS | WILEY | Published : 2008


It is often suggested that during development the brain barriers are immature. This argument stems from teleological interpretations and experimental observations of the high protein concentrations in fetal cerebrospinal fluid (CSF) and decreases in apparent permeability of passive markers during development. We argue that the developmental blood-CSF barrier restricts the passage of lipid-insoluble molecules by the same mechanism as in the adult (tight junctions) rendering the paracellular pathway an unlikely route of entry. Instead, we suggest that both protein and passive markers are transferred across the epithelium through a transcellular route. We propose that changes in volume of distr..

View full abstract