Kindlin-3 negatively regulates the release of neutrophil extracellular traps

Abstract

Neutrophils fight infections by generating reactive oxygen species (ROS) and extracellular traps (NETs). However, how neutrophils modulate ROS/NET generation is mechanistically unclear. Kindlin-3, an essential integrin activator expressed in hematopoietic cells, is required to support integrin-mediated neutrophil recruitment during inflammation. Here, we report a novel role of kindlin-3 in regulating ROS/NET generation in neutrophils. When overexpressing kindlin-3 in neutrophil-like differentiated HL-60 cells (HL-60N), ROS/NET generation from these cells were significantly suppressed. Interestingly, overexpression of a kindlin-3 mutant that is defective for interacting with integrins in HL-60N cells still inhibited ROS/NET generation, suggesting that the role of kindlin-3 in inhibiting ROS/NET signaling may be independent of its binding to integrins. Consistently, knockdown of kindlin-3 in HL-60N cells led to enhanced ROS/NET generation. In addition, bone marrow neutrophils isolated from kindlin-3-deficient mice showed elevated ROS/NET generation when compared with WT counterparts. As expected, overexpression of exogenous kindlin-3 in mouse neutrophils could suppress NET release ex vivo and in vivo. Collectively, these results demonstrate that kindlin-3 in neutrophils is involved in modulating the ROS/NET signaling, providing a novel mechanism for fine-tuning neutrophil behaviors during inflammation.

Kindlin-3 in platelets and myeloid cells differentially regulates deep vein thrombosis in mice

“…Previously, we found that presence of kindlin-3 in neutrophils is able to restrict NET release [25]. Since NETs act as a potent DVT promoter in mice, we therefore sought to investigate how kindlin-3 in neutrophils orchestrates NET release in Kindlin-3 fl/fl LysM-Cre mice in the early stenosis model.…”

“…Interaction-disrupting mutations in either kindlin-3 or the integrin β CTs lead to LAD-III like phenotypes in mice [21–23]. Kindlin can also perform integrin-independent functions [24, 25]. For example, our previous study has demonstrated that kindlin-3 in neutrophils can negatively regulate ROS/NET release, which seems to be independent of its binding to integrin [25].…”

“…Kindlin can also perform integrin-independent functions [24, 25]. For example, our previous study has demonstrated that kindlin-3 in neutrophils can negatively regulate ROS/NET release, which seems to be independent of its binding to integrin [25]. Collectively, kindlin-3 can play multifaceted roles in different blood cells.…”

Involvement of kindlin‐2 in irisin’s protection against ischaemia reperfusion‐induced liver injury in high‐fat diet‐fed mice

“…It is also essential for preserving integrity of the heart, vascular permeability in angiogenesis, chondrogenesis, regulation of podocyte structure and function, control of adipogenesis and lipid metabolism as well as bone homeostasis 56‐61 . Kindlins protect cells against oxidative damage 62‐65 . Ling Guo et al have discovered that depletion of kindlin‐2 increased ROS production 66 .…”

Site-specific phosphorylation regulates the functions of kindlin-3 in a variety of cells

“…Low-density mononuclear cells were cultured for up to 5 d at a starting density of 1 × 10 6 /ml in serum-free IMDM medium supplemented as described (Zauli et al, 1997;Shiraga et al, 1999) in the presence of 50 ng/ml murine TPO (R&D Systems) and 10 ng/ml murine IL-11 and IL-6 (Millipore Sigma). After 5 d in culture, the cells were treated with lentiviral vectors (Xu et al, 2018) expressing EGFPtagged kindlin-3 (WT), QW/AA, TS/AA, or EGFP only as described. 48 h post-transduction, the cells were either untreated or stimulated with PAR-4 agonist peptide (100 μg/ml; Bachem) for 30 min at 37°C.…”