Fig. 3
From: Physiological and pathological consequences of exosomes at the blood–brain-barrier interface
Exos can cross the BBB interface using paracellular and transcellular pathways. Due to the existence of transferrin on the Exo surface, these nanoparticles can attach to the transferrin receptor (TFR) at the luminal surface of brain ECs, leading to the formation of clathrin-coated pits and Exo internalization. The internalized Exos are direct to lysosomal degradation where the released cargo can regulate specific signaling pathways inside the ECs or cross the endothelial barrier and exist through the abluminal surface. After the production of inflammatory cytokines and certain physiological conditions, Exos can cross the BBB via a paracellular route where the function of tight junctions is not abnormal. Reprinted with permission [1], Copyright 2021. Cell & Bioscience