[Comparison of methods for isolating exosomes derived from laryngocarcinoma Hep-2 cells].

Objective: To provide a reference about choosing the methods of isolating exosomes derived from tumor cells including laryngocarcinima Hep-2 cells by comparing advantages and defects of two methods of isolation and extraction exosomes.

Method: Previously, laryngocarcinoma Hep-2 cells were cultivated massively, then the cells were processed with hot shock in 42 degrees C for 1 h. Sucrose density gradient centrifugation ultrafiltration (method 1): cells culture supernatant 90 ml was gathered, the supernatant was clarified through a 3/0.8 μm small filter to remove impurities and fragments which in larger diameter. Then the filtering fluid was concentrated and purified through sucrose density gradient centrifugation and ultrafiltration, the concentrated fluid was obtained. Exosome Isolation Kit (method 2): cells culture supernatant 4 ml was gathered, the solutions of the kit were added into the supernatant in proper sequence, then filtered by the special column, the concentrated fluid was obtained. Both products are observed by high resolution transmission electron microscopy.

Result: Both methods could isolate and extract exosomes feasibly. In single high power view of transmission electron microscopy, exosomes of method 1 disperse better, but lower density, and more impurity in background, exosomes of method 2 arrange closer, higher density, and less impurity.

Conclusion: Exosome isolation Kit require less supernatant, cost less time, process procedure briefly, harvest higher yield. It may become a new option of isolating exosomes derived from Laryngocarcinoma Hep-2 cells.