ABSTRACT
@#[Abstract] Objective: To investigate the influences of human lung adenocarcinoma PC-9 cells on tight junction proteins of blood brain barrier (BBB) under CXCR4/SDF-1 axis by establishing a model of BBB in vitro. Methods: The immortalized mouse brain microvascular endothelial Bends cells were used to establish a model of BBB in vitro by monolayer culture; Subsequently, transendothelial electric resistance (TEER) and fluorescein sodium permeability experiment were used to detect the function of in vitro BBB model and observe the effect of PC-9 cells on the function of BBB model, respectively. Western blotting was used to detect the effect of PC-9 cells on function of BBB model and expressions of endothelial tight junction proteins under the treatment of single or combined AMD3100 and SDF-1 (1 μg/ml AMD3100,100 ng/ml SDF-1, AMD3100+SDF-1). Transwell assay was used to detect the influence of CXCR4/SDF-1 axis on the ability of PC-9 cells transmigrating the cell layer of BBB model. Results: Monolayer culture of Bends cells can form tightly connected BBB withhighTEER,which reached (182.13±5.19) Ω.cm2 at the 96 h; in the meanwhile, fluorescein sodium permeability experiment showed that BBB had significantly lower permeability than that of control group ([40.31±2.43]% vs [150.10±3.17]%, P<0.05). The TEER of BBB decreased to (46.7±4.35) Ω·cm2 after coculture with PC-9 cells for 24 h, and at the same time the sodium fluorescein permeability of BBB significantly increased than that of pre-treatment ([136.32±4.93]% vs [50.24±6.21]%, P<0.05). PC-9 cells up-regulated the expressions of tight junction proteins of Bends cells under the treatment of AMD3100 (P<0.05). The number of PC-9 cells transmigrating the BBB inAMD3100 treatment group was significantly lower than that of CON group (43±2 vs 81±2, P<0.05). Conclusion: AMD3100 can reduce the ability of PC-9 cells destroying the tight junction of the BBB model established in vitro by Bends cells.