YAP Dependent Induction of CD47-Enriched Extracellular Vesicles Inhibit Dendritic Cells Activation and Ameliorate Hepatic Ischemia-Reperfusion Injury

Hepatic ischemia-reperfusion injury (IRI) is a major cause of liver damage during liver transplantation and hepatectomy, and its amelioration is an urgent unmet clinical need. Excess inflammatory response and oxidative stress contributes to the injury and Yes-associated protein (YAP) in the Hippo signaling pathway has been proved participating in it. In this study, using hepatocyte-specific YAP knockout (YAP-HKO) by crossing Yapflox/flox mice with Alb-Cre mice, we surprisingly noticed in the serum of these mice, the amount of serum extracellular vesicles (EVs) decreased after IRI. Then we found that YAP from hepatocytes regulate EVs secretion through F-actin by increasing membrane formation, as well as inhibiting the fusion of multivesicular body (MVB) and lysosomes. We further explored the essential element of YAP-induced EVs by mass spectrometry, and noticed CD47 was one of the target that highly expressed on hepatocyte-derived EVs in YAP-dependent manner. In addition, we found that CD47+ EVs can inhibit dendritic cells (DCs) activation and inflammatory responses via binding to CD172α on the surface of DCs. Finally, we isolated CD47+ EVs in IRI model and found IRI being ameliorated after treatment, suggesting that CD47+ EVs could be a potential therapeutic strategy for the treating hepatic IRI. Our data showed that CD47-enriched EVs were released in a YAP dependent manner by hepatocytes, which could inhibit DCs activation and contribute to the amelioration of hepatic IRI. Funding Statement: National Key RD the China Postdoctoral Science Foundation, Grant/Award Number: 2020M672980; the National 13th Five-Year Science and Technology Plan Major Projects of China, Grant/Award Number: 2017ZX10203205-006-001; National Natural Science Foundation of China, Grant/Award Number: 81702393, 81770648, 81670601, 81570593, 81802897, 81802897, 81900886; Key Scientific and Technological Projects of Guangdong Province, China, Grant/Award Number: 2015B020226004, 2015A030312013, 2017A030311034; Guangdong Natural Science Foundation, China, Grant/Award Number: 2017A030310373; Science and Technology Planning Project of Guangdong Province, China, Grant/Award Number:2017B030314027, 2017B020209004, 20169013, 2017A020215178; Science and Technology Planning Project of Guangzhou, China, Grant/Award Number: 2014Y2-00200, 2014Y2-00544, 201607010024, 201604020001, 201508020262, 201400000001-3 2017. Declaration of Interests: The authors have declared no conflict of interest. Ethics Approval Statement: The study protocol was approved by the Clinical Ethics Review Board of the Third Affiliated Hospital of Sun Yat- sen University. Informed consent was obtained according to the Declaration of Helsinki. All animal studies were approved and monitored by the animal experimental ethics committee of the Third Affiliated hospital of Sun-Yat Sen University.