Hu Wanbin, van Steijn Leonie, Li Chen, Verbeek Fons J, Cao Lu, Merks Roeland M H, Spaink Herman P
Institute of Biology, Leiden University, Leiden, Netherlands.
Mathematical Institute, Leiden University, Leiden, Netherlands.
Front Cell Dev Biol. 2021 Feb 15;9:624571. doi: 10.3389/fcell.2021.624571. eCollection 2021.
Toll-like receptor (TLR) signaling via myeloid differentiation factor 88 protein (MyD88) has been indicated to be involved in the response to wounding. It remains unknown whether the putative role of MyD88 in wounding responses is due to a control of leukocyte cell migration. The aim of this study was to explore whether TLR2 and MyD88 are involved in modulating neutrophil and macrophage cell migration behavior upon zebrafish larval tail wounding. Live cell imaging of tail-wounded larvae was performed in and mutants and their corresponding wild type siblings. In order to visualize cell migration following tissue damage, we constructed double transgenic lines with fluorescent markers for macrophages and neutrophils in all mutant and sibling zebrafish lines. Three days post fertilization (dpf), tail-wounded larvae were studied using confocal laser scanning microscopy (CLSM) to quantify the number of recruited cells at the wounding area. We found that in both and groups the recruited neutrophil and macrophage numbers are decreased compared to their wild type sibling controls. Through analyses of neutrophil and macrophage migration patterns, we demonstrated that both and control the migration direction of distant neutrophils upon wounding. Furthermore, in both the and the mutants, macrophages migrated more slowly toward the wound edge. Taken together, our findings show that and are involved in responses to tail wounding by regulating the behavior and speed of leukocyte migration .
通过髓样分化因子88蛋白（MyD88）的Toll样受体（TLR）信号传导已被表明参与对伤口的反应。MyD88在伤口反应中的假定作用是否归因于对白细胞迁移的控制仍不清楚。本研究的目的是探讨TLR2和MyD88是否参与调节斑马鱼幼体尾部受伤后中性粒细胞和巨噬细胞的迁移行为。在MyD88和TLR2突变体及其相应的野生型同胞中对尾部受伤的幼体进行活细胞成像。为了可视化组织损伤后的细胞迁移，我们在所有突变体和同胞斑马鱼品系中构建了带有巨噬细胞和中性粒细胞荧光标记的双转基因品系。受精后三天（dpf），使用共聚焦激光扫描显微镜（CLSM）研究尾部受伤的幼体，以量化伤口区域募集细胞的数量。我们发现，与野生型同胞对照相比，MyD88和TLR2组中募集的中性粒细胞和巨噬细胞数量均减少。通过对中性粒细胞和巨噬细胞迁移模式的分析，我们证明MyD88和TLR2均控制受伤后远处中性粒细胞的迁移方向。此外，在MyD88和TLR2突变体中，巨噬细胞向伤口边缘迁移的速度都更慢。综上所述，我们的研究结果表明，MyD88和TLR2通过调节白细胞迁移的行为和速度参与对尾部伤口的反应。
