The Healing Power of Neutrophils

Neutrophils promptly accumulate in large numbers at sites of tissue injury. Injuries to the skin or mucosae disrupt barriers against the external environment, and the bactericidal actions of neutrophils are important in preventing microbial invasion. Neutrophils have also been associated with exacerbated inflammation, for example in non-healing wounds or in conditions such as inflammatory bowel disease (IBD). However, additional neutrophil functions important for angiogenesis and tissue restoration have been uncovered in models of sterile and ischemic injury, as well as in tumors. These functions are also relevant in healing skin and mucosal wounds, and can be impaired in conditions associated with non-healing wounds, such as diabetes. Here, we discuss our current understanding of neutrophil contributions to healing, and how the latter can be compromised in disease. Tissue-restorative and proangiogenic functions of neutrophils have been uncovered in models of sterile and ischemic injury, as well as in tumors.Neutrophils are important for limiting microbial invasion at sites of skin or mucosal injury, but they also contribute to tissue restoration during wound healing.At the site of injury, neutrophils initiate healing via direct effects on angiogenesis and cell proliferation.The healing capacities of neutrophils are impaired in patients with chronic diseases associated with compromised healing, such as in diabetes.Understanding the contributions of neutrophils to the healing of different types of injuries will help to uncover potential targets that might be therapeutically exploited in disease states where tissue healing can be compromised.