[Isolation and biological characteristics of exosomes derived from periodontal ligament stem cells].

Purpose: To isolate and identify exosomes derived from periodontal ligament stem cells (PDLSCs) collected by ultracentrifugation.

Methods: Using the limiting dilution technique, human PDLSCs were isolated and expanded. The cell culture supernatant of PDLSCs was collected. Exosomes were collected and purified with a ultracentrifugation method. Biological characteristics of exosomes derived from PDLSCs were measured by transmission electron microscopy (TEM), Western blot and nanosight tracing analysis (NTA).

Results: Exosomes could be successfully isolated from the supernatant of PDLSCs by a ultracentrifugation method. Under TEM, the PDLSC-derived exosomes exhibited elliptic or saucer-like shape and the central area had lower electron density than the circum area. The PDLSC-derived exosomes could express the common surface adhesion molecules CD9, CD63, CD81 and TSG101. NTA results showed that the collected exosomes had a size around (119±12.1) nm and an approximate concentration of (3.80±0.39)×10 particles/mL.

Conclusions: Exosomes derived from PDLSCs can be collected by a ultracentrifugation method, which expresses common membrane proteins and morphological characteristics of exosomes.