Abstract: Objective To construct and evaluate the in vitro models of blood-brain barrier (BBB)and to analyze their structural and functional characteristics. Methods Human microvascular endothelial cell line(hCMEC/D3), Uppsala 87 malignant glioma cell line(U87MG) and human brain vascular pericyte(HBVP) cell line were used to construct blood-brain barrier cell models. The models were divided into single-culture model, bi-culture (hCMEC/D3+U87MG or HBVP), no-contact co-culture model, semi-contact co-culture and full-contact co-culture model according to different cell types and cell locations. The permeability and tightness of the models as well as the expression of related proteins and genes were detected for comparing and analyzing the structural and functional characteristics of different models. Results Compared with the single-culture model and the bi-culture model, the permeability and compactness of the co-culture model decreased and the expression of BBB-related genes and proteins also increased(P＜0.05). In the co-culture models, full-contact co-culture model showed higher compactness(P＜0.01) and higher BBB-related protein and gene expression. Semi-contact and full-contact culture model had lower permeability(P＜0.05). Conclusions Full-contact co-culture model has better BBB-related properties and is more suitable for BBB research.

Key words: endothelial cell, astrocyte, pericyte, blood-brain barrier, co-culture