Establishment of coculture model of blood-brain barrier in vitro for nanoparticle's transcytosis and toxicity evaluation / 药学学报

ABSTRACT

Aim A method of coculture of brain capillary endothelial cells (BCECs) and astrocytes of rats was used to evaluate nanoparticle' s blood-brain barrier (BBB) transcytosis and toxicity at the endothelial tight junction. Methods A lipophilic fluorescent probe, 6-coumarin, was incorporated in poly(ethyleneglycol)-poly (lactide) nanoparticle using double emulsion/solvent evaporation method. BCECs and astrocytes were firstly isolated from brain of newborn rats and characterized by their morphology and immunocytochemistry staining, separately. Subsequently, a coculture model with BCECs on the top of micro-porous membrane of cell culture insert and astrocytes on the bottom side was established. The permeability of 14C-labeled sucrose and nanoparticle were determined, separately. Results The meanweight-based diameter of 6-coumarin loaded nanoparticles was ( 102.4 ± 6.8) nm, with zeta potential of ( - 16.81 ± 1.05) mV. BCECs were positive for factor Ⅷ staining and glial fibrillary acidic protein was tight junction between BCECs in the coculture model could be visualized by both scanning electron microscopy and transmission electron microscopy. The unchanged paracellular transport of sucrose proved vivo situation for examination of the permeability of nanoparticle and toxicity evaluation.