期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2016
卷号：113
期号：23
页码：E3240-E3249
DOI：10.1073/pnas.1521453113
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Resolution of inflammation has emerged as an active process in immunobiology, with cells of the mononuclear phagocyte system being critical in mediating efferocytosis and wound debridement and bridging the gap between innate and adaptive immunity. Here we investigated the roles of cytochrome P450 (CYP)-derived epoxy-oxylipins in a well-characterized model of sterile resolving peritonitis in the mouse. Epoxy-oxylipins were produced in a biphasic manner during the peaks of acute (4 h) and resolution phases (24–48 h) of the response. The epoxygenase inhibitor SKF525A (epoxI) given at 24 h selectively inhibited arachidonic acid- and linoleic acid-derived CYP450-epoxy-oxlipins and resulted in a dramatic influx in monocytes. The epoxI-recruited monocytes were strongly GR1+, Ly6chi, CCR2hi, CCL2hi, and CX3CR1lo. In addition, expression of F4/80 and the recruitment of T cells, B cells, and dendritic cells were suppressed. sEH (Ephx2)−/− mice, which have elevated epoxy-oxylipins, demonstrated opposing effects to epoxI-treated mice: reduced Ly6chi monocytes and elevated F4/80hi macrophages and B, T, and dendritic cells. Ly6chi and Ly6clo monocytes, resident macrophages, and recruited dendritic cells all showed a dramatic change in their resolution signature following in vivo epoxI treatment. Markers of macrophage differentiation CD11b, MerTK, and CD103 were reduced, and monocyte-derived macrophages and resident macrophages ex vivo showed greatly impaired phagocytosis of zymosan and efferocytosis of apoptotic thymocytes following epoxI treatment. These findings demonstrate that epoxy-oxylipins have a critical role in monocyte lineage recruitment and activity to promote inflammatory resolution and represent a previously unidentified internal regulatory system governing the establishment of adaptive immunity.
