Innate immune responses to trauma

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Trauma can affect any individual at any location and at any time over a lifespan. The disruption of macrobarriers and microbarriers induces instant activation of innate immunity. The subsequent complex response, designed to limit further damage and induce healing, also represents a major driver of complications and fatal outcome after injury. This Review aims to provide basic concepts about the posttraumatic response and is focused on the interactive events of innate immunity at frequent sites of injury: the endothelium at large, and sites within the lungs, inside and outside the brain and at the gut barrier.

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Fig. 1: Protective and harmful innate immune responses to trauma.
Fig. 2: Activation of innate immune responses and endothelial dysfunction after trauma.
Fig. 3: Innate immune responses in the lungs following trauma.
Fig. 4: Cerebral and extracerebral challenges to the innate immune system.
Fig. 5: Trauma-induced breakdown of protective cell barriers in the gut.


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We thank R. Halbgebauer and D. McClellan for editorial assistance, and S. Denk for graphical support. Supported by the German Research Foundation (DFG CRC1149 and DFG EI866/5-1), the US National Institutes of Health (AI068730, AI030040) and the European Community’s Seventh Framework Programme (under grant agreement number 602699 (DIREKT)).

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All authors researched the data for the article, contributed to discussions of the content, wrote the text and reviewed or edited the article before submission.

Correspondence to Markus Huber-Lang.

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Competing interests

M.H.-L. and P.A.W. hold a patent on compositions and methods for the diagnosis and treatment of sepsis (US 7455837). J.D.L. is the founder of Amyndas Pharmaceuticals, which is developing complement inhibitors (including third-generation compstatin analogs such as AMY-101), and is the inventor of patents or patent applications that describe the use of complement inhibitors for therapeutic purposes, some of which are developed by Amyndas Pharmaceuticals. J.D.L. is also the inventor of the compstatin technology licensed to Apellis Pharmaceuticals (4(1MeW)7W/POT-4/APL-1 and PEGylated derivatives such as APL-2).

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