Figure 1.

Exosomes secreted from HG-treated Schwann cells suppress axonal growth. A, B) Exosomes isolated by differential ultracentrifugation from the supernatant of HG-treated Schwann cells had an average particle size of ∼100 nm (A) and exhibited exosomal marker proteins of Alix, CD63, and Hsp70 measured by Western blot analysis (B). C) Microfluidic device showing the cell body and axonal compartments. When they were cultured in the cell body compartment, DRG neurons extend their axons into the axonal compartment by crossing microgrooves. D) Quantitative data of axonal length when HG exosomes at concentrations of 1 × 10⁷ and 1 × 10⁸ particles/ml were added into both cell body and axonal compartments. E, F) Representative immunofluorescent images (E) and quantitative data (F) of axonal length when HG exosomes at concentrations of 1 × 10⁷ and 1 × 10⁸ particles/ml were added to the axonal compartment alone show that HG exosomes reduced axonal lengths (n = 6 chambers/3 individual experiments/group). Scale bars, 100 μm. *P < 0.05.