Fig. 1.

Schematic of MSNPs delivery system. a Design of RSV loaded MSNPs with peptide bind PLA-coating. b An in vitro BBB model with RBECs cultured on semi-permeable membranes of Transwell chamber with the microglia cells grown on the bottom of the well. MSNPs with covalently attached LDL ligands are recognized and internalized by LDL receptors of RBECs. PMA or LPS stimulations activate the inflammatory response of microglia to release reactive species. c PMA or LPS stimulated microglia produce superoxide or nitric oxide which can accelerate the degradation of PLA and accelerate RSV release to control the oxidative stress