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Review
. 2016 Dec;100(12):2601-2610.
doi: 10.1097/TP.0000000000001411.

Innate Immune Regulations and Liver Ischemia-Reperfusion Injury

Affiliations
Review

Innate Immune Regulations and Liver Ischemia-Reperfusion Injury

Ling Lu et al. Transplantation. 2016 Dec.

Abstract

Liver ischemia reperfusion activates innate immune system to drive the full development of inflammatory hepatocellular injury. Damage-associated molecular patterns (DAMPs) stimulate myeloid and dendritic cells via pattern recognition receptors (PRRs) to initiate the immune response. Complex intracellular signaling network transduces inflammatory signaling to regulate both innate immune cell activation and parenchymal cell death. Recent studies have revealed that DAMPs may trigger not only proinflammatory but also immune regulatory responses by activating different PRRs or distinctive intracellular signaling pathways or in special cell populations. Additionally, tissue injury milieu activates PRR-independent receptors which also regulate inflammatory disease processes. Thus, the innate immune mechanism of liver ischemia-reperfusion injury involves diverse molecular and cellular interactions, subjected to both endogenous and exogenous regulation in different cells. A better understanding of these complicated regulatory pathways/network is imperative for us in designing safe and effective therapeutic strategy to ameliorate liver ischemia-reperfusion injury in patients.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Fig. 1
Fig. 1
Innate immune activation and regulation - A multi-cellular and -molecular interaction network. Liver innate immune activation involves multiple cells, including Kupffer cells/macrophages, neutrophils, dendritic cells, as well as hepatocytes. Initial hepatocellular damages due to ischemia result in releases of extracellular HMGB1, histone/DNA and ATP. These DAMPs stimulate different cells via TLR4/MD2, RAGE (by HMGB1) and TLR9, NLRP3 (by histone/DNA, ATP) to activate (+) or inhibit (−) liver inflammatory immune responses, leading to productions of cytokines/chemokines, ROSs, DAMPs (HMGB1, ATP) and cytotoxic molecules, including NETs by neutrophils. The proinflammatory milieu recruits and activate more innate and adaptive immune cells into inflamed livers and causes further hepatocellular damages; while immune regulatory milieu, such as IL-10, inhibits inflammation. Hepatocytes actively secrete HMGB1 upon TLR4 stimulation or IR stress. Resident and infiltrating DCs/macrophages respond to DAMPs differently. Rather than proinflammatory activation, resident DCs/macrophages produce IL-10 to inhibit tissue inflammation. Cells also upregulate CD24/Siglec, purinergic receptors (P1/P2) and CD39/CD73 upon inflammatory stimulation, which play immune regulatory roles in liver inflammation. CD39/CD73 converts ATP into adenosine, which binds to P1 receptors to facilitate M2 macrophage activation.

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References

    1. Thaiss CA, Levy M, Itav S, Elinav E. Integration of Innate Immune Signaling. Trends Immunol. 2016;37(2):84–101. - PubMed
    1. Wu HS, Zhang JX, Wang L, Tian Y, Wang H, Rotstein O. Toll-like receptor 4 involvement in hepatic ischemia/reperfusion injury in mice. Hepatobiliary Pancreat Dis Int. 2004;3(2):250–253. - PubMed
    1. Zhai Y, Shen XD, O’Connell R, et al. Cutting edge: TLR4 activation mediates liver ischemia/reperfusion inflammatory response via IFN regulatory factor 3-dependent MyD88-independent pathway. J Immunol. 2004;173(12):7115–7119. - PubMed
    1. Ellett JD, Evans ZP, Atkinson C, Schmidt MG, Schnellmann RG, Chavin KD. Toll-like receptor 4 is a key mediator of murine steatotic liver warm ischemia/reperfusion injury. Liver Transpl. 2009;15(9):1101–1109. - PMC - PubMed
    1. Gehrau RC, Mas VR, Dumur CI, et al. Donor Hepatic Steatosis Induce Exacerbated Ischemia-Reperfusion Injury Through Activation of Innate Immune Response Molecular Pathways. Transplantation. 2015;99(12):2523–2533. - PMC - PubMed