Fig. 2.

Immunomodulatory screening of extracellular vesicles from adipose stromal/stem cells (ASCs) of different donors. EVs from the ASC supernatant were isolated via differential (ultra)-centrifugation. Resting BV-2 cells were primed for 3 h with 1 µg/ml LPS before addition of 8 EVs/cell (quantification by flow cytometry) for 24 h. The secretion of TNF-α was evaluated by ELISA in the cell-culture supernatant as an activation read-out for the LPS-stimulated microglia cells. (A) The TNF-α levels from all donors (n = 12) were compared. The donors were separated into (B) non-immunomodulatory (n = 6) and (C) immunomodulatory donors (n = 6). Statistics were calculated with the Mann Whitney U-Test. NC = negative control (D) Further characterization and functional analysis of EVs were carried out for the immunomodulatory EVs as shown in the scheme