From the Research
Neutrophils arrive at a site of inflammation through a coordinated process involving both margination and chemotaxis, with the most recent evidence suggesting that selectin-mediated signaling plays a crucial role in regulating integrin activity in neutrophils 1. The process of neutrophil recruitment to sites of inflammation is complex and involves multiple steps, including margination, rolling, adhesion, and transmigration. Margination occurs when neutrophils slow down and roll along the endothelial wall of blood vessels near the inflamed area, mediated by selectins on both the neutrophil and endothelial cell surfaces. Following margination, neutrophils respond to chemotactic factors released at the site of injury or infection, such as IL-8, complement component C5a, leukotriene B4, and bacterial products like formylated peptides.
- The concentration gradient of these factors guides neutrophils through the vessel wall (diapedesis) and toward the specific site of inflammation.
- Neutrophil chemotaxis is a critical component of the innate immune response, allowing neutrophils to migrate towards sites of infection and inflammation in response to chemical gradients 2.
- The process of chemotaxis is regulated by a complex interplay of signaling pathways, including the Rho family of GTPases and heptahelical G protein-coupled receptors (GPCRs) 3.
- Recent studies have shed light on the regulation of integrin activity in neutrophils, highlighting the importance of selectin-mediated signaling in this process 1.
- Overall, the coordinated process of margination and chemotaxis allows neutrophils to rapidly and efficiently respond to sites of inflammation, playing a critical role in the innate immune response.