Trauma hemorrhage (TH) and subsequent sepsis are well known to frequently result in severe organ damage. Although macrophage-activating lipopeptide-2 (MALP-2) has been described to exert beneficial effects on organ damage, and further clinical course after both isolated trauma and sepsis, little is known about the impact of MALP-2 in a clinically realistic two-hit scenario of TH and subsequent sepsis. As the liver represents a key organ for the posttraumatic immune response and development of complications, the effects of MALP-2 on the posttraumatic hepatic immunologic response and tissue damage were investigated in a murine “two-hit” model. In C57BL/6 mice, blood pressure-controlled (35 ± 5 mm Hg) TH was induced. Cecal ligation and puncture (CLP) was performed 48 h after TH. Mice were divided into two control groups (control 1, TH and laparotomy without CLP; control 2, TH and CLP) and three experimental groups (TH + CLP) treated with MALP-2 at different timepoints (ETH, end of TH; ECLP, end of CLP; 6CLP, 6 h after CLP). The observation time lasted for 168 h after induction of TH. Kupffer cells (KC) were isolated and cultured, and MPO activity was analyzed. Cell culture supernatants were taken for cytokine analysis (TNF-α, IL-6, MCP-1, GM-CSF, IL-10). Histological analysis was performed using the Hepatic Injury Severity Scoring (HISS). Statistical evaluation was carried out using SPSS (version 24.0.0; IBM, Armonk, NY, USA). MPO activity of control 1 group was lowest compared with all the other groups (p < 0.01). MPO activity of control 2 group was significantly higher than that in all experimental groups (ETH (p < 0.01), ECLP (p < 0.01), and 6CLP (p = 0.03)). Within the experimental groups, MPO activity was significantly reduced in the ETH (p = 0.04) and the ECLP (p < 0.01) groups compared with the 6CLP group. Moreover, ETH was also associated with the most pronounced reduction of cytokine expression by KC (p < 0.05). HISS revealed the largest damage in the group control 2. TH and subsequent sepsis lead to a distinct immunologic reaction in the liver with an increase of cytokine expression of KC and pronounced infiltration of granulocytes with associated severe tissue damage. MALP application decreases the hepatic immune response and liver damage, with the most pronounced effects if applied at the end of TH.

众所周知，创伤性出血 (TH) 和随后的败血症经常导致严重的器官损伤。尽管巨噬细胞活化脂肽 2 (MALP-2) 已被描述为对器官损伤以及孤立的创伤和脓毒症后的进一步临床过程产生有益影响，但关于 MALP-2 在临床上现实的双重治疗中的影响知之甚少。 TH 和随后的败血症的打击情景。由于肝脏是创伤后免疫反应和并发症发展的关键器官，因此在小鼠“二次打击”模型中研究了 MALP-2 对创伤后肝脏免疫反应和组织损伤的影响。在 C57BL/6 小鼠中，诱导了血压控制 (35 ± 5 mm Hg) TH。在 TH 后 48 小时进行盲肠结扎和穿刺 (CLP)。将小鼠分为两个对照组（对照组1，无 CLP 的 TH 和剖腹手术；对照 2，TH 和 CLP）和三个实验组（TH + CLP）在不同时间点（ETH，TH 结束；ECLP，CLP 结束；6CLP，CLP 后 6 小时）用 MALP-2 处理。TH诱导后观察时间持续168小时。分离和培养枯否细胞（KC），分析MPO活性。取细胞培养上清液进行细胞因子分析（TNF-α、IL-6、MCP-1、GM-CSF、IL-10）。使用肝损伤严重程度评分（HISS）进行组织学分析。使用 SPSS（版本 24.0.0；IBM，Armonk，NY，USA）进行统计评估。与其他所有组相比，对照组 1 组的 MPO 活性最低（CLP 后 6 小时）。TH诱导后观察时间持续168小时。分离和培养枯否细胞（KC），分析MPO活性。取细胞培养上清液进行细胞因子分析（TNF-α、IL-6、MCP-1、GM-CSF、IL-10）。使用肝损伤严重程度评分（HISS）进行组织学分析。使用 SPSS（版本 24.0.0；IBM，Armonk，NY，USA）进行统计评估。与其他所有组相比，对照组 1 组的 MPO 活性最低（CLP 后 6 小时）。TH诱导后观察时间持续168小时。分离和培养枯否细胞（KC），分析MPO活性。取细胞培养上清液进行细胞因子分析（TNF-α、IL-6、MCP-1、GM-CSF、IL-10）。使用肝损伤严重程度评分（HISS）进行组织学分析。使用 SPSS（版本 24.0.0；IBM，Armonk，NY，USA）进行统计评估。与其他所有组相比，对照组 1 组的 MPO 活性最低（使用 SPSS（版本 24.0.0；IBM，Armonk，NY，USA）进行统计评估。与其他所有组相比，对照组 1 组的 MPO 活性最低（使用 SPSS（版本 24.0.0；IBM，Armonk，NY，USA）进行统计评估。与其他所有组相比，对照组 1 组的 MPO 活性最低（p  < 0.01)。对照组2的MPO活性显着高于所有实验组（ETH（p  < 0.01）、ECLP（p  < 0.01）和6CLP（p  = 0.03））。 在实验组内，与 6CLP 组相比， ETH ( p  = 0.04) 和 ECLP ( p < 0.01) 组的 MPO 活性显着降低。此外，ETH 还与 KC 最显着降低细胞因子表达有关（p < 0.05)。HISS 揭示了对照组 2 中最大的损伤。TH 和随后的败血症导致肝脏中出现明显的免疫反应，KC 的细胞因子表达增加，粒细胞明显浸润并伴有严重的组织损伤。MALP 应用可降低肝脏免疫反应和肝损伤，如果在 TH 结束时应用，效果最明显。