Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison, WI 53705, USA.
Currently at School of Medicine and Public Health, University of Wisconsin, Madison, WI 53705, USA.
Biol Open. 2022 Mar 15;11(3). doi: 10.1242/bio.058559. Epub 2022 Mar 9.
The inflammatory response is a vital defense mechanism against trauma and pathogen induced damage, but equally important is its appropriate resolution. In some instances of severe trauma or sustained infection, inappropriate and persistent activation of the immune response can occur, resulting in a dangerous systemic inflammatory response. Untreated, this systemic inflammatory response can lead to tissue damage, organ shutdown, and death. Replicating this condition in tractable model organisms can provide insight into the mechanisms involved in the induction, maintenance, and resolution of inflammation. To that end, we developed a non-invasive, inducible, and reversible model of systemic inflammation in zebrafish. Using the Gal4-EcR/UAS system activated by the ecdysone analog tebufenozide, we generated transgenic zebrafish that allow for chemically induced, ubiquitous secretion of the mature form of zebrafish interleukin-1β (Il-1βmat) in both larval and adult developmental stages. To ensure a robust immune response, we attached a strong signal peptide from the Gaussia princeps luciferase enzyme to promote active secretion of the cytokine. We observe a dose-dependent inflammatory response involving neutrophil expansion accompanied by tissue damage and reduced survival. Washout of tebufenozide permits inflammation resolution. We also establish the utility of this model for the identification of small molecule anti-inflammatory compounds by treatment with the immunosuppressant rapamycin. Taken together, these features make this model a valuable new tool that can aid in identifying potential new therapies while broadening our understanding of systemic inflammation, its impact on the immune system, and its resolution.
炎症反应是一种对抗创伤和病原体引起的损伤的重要防御机制，但同样重要的是它的适当解决。在某些严重创伤或持续感染的情况下，免疫反应可能会不适当地持续激活，导致危险的全身性炎症反应。如果不加治疗，这种全身性炎症反应会导致组织损伤、器官衰竭和死亡。在可处理的模式生物中复制这种情况，可以深入了解炎症的诱导、维持和解决所涉及的机制。为此，我们在斑马鱼中开发了一种非侵入性、可诱导和可逆转的全身性炎症模型。我们使用 Gal4-EcR/UAS 系统，该系统由蜕皮激素类似物 Tebufenozide 激活，生成了允许在幼虫和成年发育阶段化学诱导、广泛分泌成熟形式的斑马鱼白细胞介素-1β（Il-1βmat）的转基因斑马鱼。为了确保强烈的免疫反应，我们附着了来自 Gaussia princeps 荧光素酶的强信号肽，以促进细胞因子的主动分泌。我们观察到一种剂量依赖性的炎症反应，涉及中性粒细胞的扩张，伴有组织损伤和存活率降低。Tebufenozide 的冲洗允许炎症的解决。我们还通过用免疫抑制剂雷帕霉素治疗，证明了这种模型在鉴定小分子抗炎化合物方面的效用。综上所述，这些特征使该模型成为一种有价值的新工具，可以帮助确定潜在的新疗法，同时扩大我们对全身性炎症、其对免疫系统的影响及其解决的理解。
