Comparison of Plasma- and Adipose Tissue-Derived Stromal Cell Extracellular Vesicles for Schwann Cell Proliferation and Cost-Effectiveness

BACKGROUND: Preparation of Extracellular vesicles (EVs) from cell cultures is labor-intensive. Plasma-derived EVs have demonstrated proliferative effects. The aim of this study was to compare the proliferative effect of plasma EVs on Schwann cells (SC) and to assess the cost structure of EVs derived from plasma versus Adipose tissue-derived stromal cells (AdSCs). METHODS: EVs isolated from rat platelet-rich plasma (PRP), platelet-poor plasma (PPP), and AdSC cell culture were assessed by quantity, size, and phenotypic markers. Both plasma-EVs in three dosages were added to primary rat SC cultures. As controls, SCs were incubated in standard growth medium, PRP, PPP or EVs derived from AdSCs and the proliferation rate, SC length-to-width ratio and increase in confluency was determined. Furthermore, the cost structure and working hours associated with EV preparation were calculated. RESULTS: EVs derived from AdSCs, PPP and PRP were about the same size with a significantly higher concentration of EVs found in plasma. After the addition of PRP, PPP, PRP-EVs, PPP-EVs, and AdSC-EV to SC cultures, only AdSC-EVs and PRP-EVs in highest concentration reached a significantly increased proliferation. Cost and labor analysis revealed that plasma-derived EVs could be obtained more efficiently, with reduced time and expense. CONCLUSIONS: Compared to AdSC-EVs, PRP-EVs were isolated at a significantly higher concentration with lower cost and reduced labor time. Given their autologous origin, PRP-EVs may serve as a promising option to increase proliferation of Schwann cells. The results of this study deliver preliminary insights, and further studies are needed to explore their full regenerative potential.