Additional file 5: Figure S5. of The release and trans-synaptic transmission of Tau via exosomes

Uptake and transmission of TauCFP by neurons cultured in microfluidic chambers via exosomes derived from cultured neurons. (A) Nanoparticle tracking analysis of exosomes derived from primary neurons transfected with TauCFP. The size distribution peaks at ~90 nm, indicating the enrichment of exosomes in the preparations. (B) Uptake and transmission of exosomes containing TauCFP isolated as in (A) by neurons cultured in microfluidic chambers with long microgrooves (900 nm). The 1st order neurons at DIV25 were treated for 24 h with exosomes (20 μg) isolated from primary cortical neurons infected with adeno-virus expressing TauCFP, when the 2nd order neurons were at DIV11. Neurons were then fixed and stained for immunofluorescence microscopy with antibodies against MAP2 (red). Arrows denote TauCFP exosomes. Scale bar = 10 μm. Note that TauCFP exosomes were detected in the 2nd order neurons on the neuritic side, indicating their uptake by 1st order neurons on the somal side, transport across the microgrooves, and synaptic transmission to the neurons on the neuritic side. (PNG 157 kb)