Non-invasive approaches for drug delivery to the brain based on the receptor mediated transport

The blood brain barrier (BBB) is a physical and biochemical barrier that prevents entry of toxic compounds into brain for preserving homeostasis. However, the BBB also strictly limits influx of most therapeutic agents into the brain. One promising method for overcoming this problem to deliver drugs is receptor mediated transport (RMT) system, which employs the vesicular trafficking machinery to transport substrates across the BBB endothelium in a noninvasive manner. The conjugates of drug or drug-loaded vector linked with appropriate ligands specifically binds to the endogenous targeting receptor on the surface of the endothelial cells. Then drugs could enter the cell body by means of transcytosis and eventual releasing into the brain parenchyma. Over the past 20years, there have been significant developments of RMT targeting strategies. Here, we will review the recent advance of various promising RMT systems and discuss the capability of these approaches for drug delivery to the brain.