Umbilical cord blood plasma-derived exosomes as a novel therapy to reverse liver fibrosis

BACKGROUND: Cirrhosis is a chronic liver disease whereby scar tissue replaces healthy liver parenchyma, leading to disruption of the liver architecture and hepatic dysfunction. Currently, there is no effective disease-modifying therapy for liver fibrosis. Recently, our group demonstrated that human umbilical cord blood (UCB) plasma possesses therapeutic effects in a rat model of acute liver failure. METHODS: In the current study, we tested whether exosomes (Exo) existed in UCB plasma and if they produced any antifibrotic benefits in a liver fibrosis model. RESULTS: Our results showed that UCB-Exo improved liver function and increased matrix metalloproteinase/tissue inhibitor of metalloproteinase degradation to reduce the degree of fibrosis. Moreover, UCB-Exo were found to suppress hepatic stellate cell (HSC) activity in vitro. These effects were associated with suppression of transforming growth factor-β/inhibitor of DNA binding 1 signaling. CONCLUSIONS: These results further support that UCB-Exo have antifibrotic effects in mice with liver fibrosis and activated HSCs and may herald a new cell-free antifibrotic therapy.