肝臓由来エクソソームは補体活性化を阻害することにより肝虚血再灌流（IR）障害を軽減する

Exosomes are specialized secreted vesicles for intercellular communication and signaling pathways as specialized secreted vesicles. Multiple studies have suggested the potential roles of hepatocyte-derived exosomes as biomarkers of liver injury and facilitators of hepatocyte proliferation and liver regeneration.

By utilizing murine models of hepatic ischemia-reperfusion injury (IRI), we examined the impact of hepatocyte-derived exosomes on mitigating hepatic IRI.

Our experiments have demonstrated that significantly lower levels of alanine transaminase, aspartate transaminase, and lactate dehydrogenase in mice treated with hepatocyte-derived exosomes compared with mice treated with phosphate-buffered saline (PBS). Furthermore, hepatocyte-derived exosomes inhibited hepatocyte apoptosis, reduced levels of inflammatory cytokines, and suppressed the entry of inflammatory cells into the liver following hepatic IRI. Complement 3d (C3d) expression showed a notable decrease in exosome-treated mice compared with PBS-treated mice, suggesting that hepatocyte-derived exosomes effectively inhibited complement activation during hepatic IRI. Blocking the fusion of exosomes with cells using Annexin V weakened the protective effects of the exosomes against hepatic IRI.

Our findings highlight the ability of hepatocyte-derived exosomes to mitigate hepatic IRI by inhibiting complement activation. These results reveal a novel role for exosomes in blocking complement activation, suggesting a potential new therapeutic avenue for preventing hepatic IRI.