Neutrophils Found to Reinforce Skin, Opening New Avenues for Treating Skin Diseases

Researchers at the Centro Nacional de Investigaciones Cardiovasculares (CNIC) have discovered that neutrophils, a type of immune cell, play a crucial role in reinforcing the skin's structure and integrity. Published in *Nature*, the study reveals that these neutrophils produce extracellular matrix, contributing to the skin's resistance and acting as a barrier against harmful substances. This finding suggests the immune system not only combats infections but also physically strengthens the skin. The research indicates that neutrophils actively respond to skin injuries by forming protective structures around wounds, preventing bacteria and toxins from entering. The structural function of these neutrophils is regulated by the TGF-β signaling pathway. Disabling this pathway led to decreased extracellular matrix formation, resulting in more fragile skin. Furthermore, the study found that these neutrophils operate on a circadian rhythm, regulating extracellular matrix production based on the body's biological clock. This discovery opens potential avenues for developing therapies that strengthen the skin barrier in patients with inflammatory diseases, immunological disorders, diabetes, and age-related conditions. The research also has implications for understanding fibrotic processes and cancer.