Isolation and culture of human brain microvessel endothelial cells for the study of blood-brain barrier properties in vitro.

A simplified protocol for isolating brain microvessel endothelial cells (BMEC) from human cortex and culturing them on a thick collagen plug is described. This method results in the establishment of monolayers of BMEC that retain numerous properties indicative of the blood-brain barrier (BBB) phenotype, such as elevated transendothelial electrical resistance, attenuated paracellular flux of sucrose, peripheral actin filament distribution and asymmetric localization of the efflux peptide, P-glycoprotein, to the apical (luminal) BMEC surface. The novel 3-dimensional nature of this model system renders it ideally suitable for assaying such varied aspects of BBB physiology as solute transport, pathogen penetrance, leukocyte infiltration and tumor metastasis into the brain. Moreover, the fact that the system is derived from human brain allows for the study of pathogenetic mechanisms that may only be operative in humans.