Immune cells called neutrophils can trap and kill bacteria by releasing webs called neutrophil extracellular traps (NETs). This new study (Rossi lab) develops a new method that can more reliably measure NETs quickly and objectively over current methods. This could increase understanding of diseases such as lupus and cancer, and help identify therapies that will target the harmful NET production in these diseases. Neutrophils are immune cells that help fight infection. One of their defence strategies is to release sticky webs made of DNA and proteins, called neutrophil extracellular traps (NETs) which can trap and kill bacteria. However, when too many NETs are produced, or when they aren’t cleared properly, they can contribute to diseases such as lupus, rheumatoid arthritis, sepsis, cystic fibrosis, abnormal blood clots and cancer. Illustration of neutrophils (pink) releasing neutrophil extracellular traps (NETs) made up of DNA and proteins (red and green) Scientists need reliable ways to measure NETs to understand these diseases better, enabling the discovery of new therapies targeting harmful NET production. However, current methods are either slow, subjective, or prone to mistakes, for example, confusing NETs with dying cells. This new method strengthens the foundation of NET research and improves confidence in experimental results. As more researchers adopt this method, it could become a standard approach for studying NETs in diseases. Prof Adriano Rossi IRR Group Leader and paper’s corresponding author In this study, researchers developed a fast, objective laboratory test using a technology called flow cytometry (where a machine rapidly examines thousands of cells, one by one).Instead of measuring only a single NET marker (which can lead to false positives), researchers designed the test to detect two key NET markers at the same time. These include DNA bound to specific proteins called Histone H1 and Histone H2A. Cells highly expressing both markers were classified as producing NETs.They found that the new method could accurately detect NET formation and did not confuse NETs with dying cells. The method could also correctly distinguish between different biological pathways that trigger NET formation and could be used on both fixed and live samples.Importantly, this study found that using two markers instead of one significantly reduced false positives. This method can also be expanded to include additional NET markers for even greater specificity, offering a flexible platform that could be adapted.Future work could include applying the assay to clinical patient samples or studying NET formation over time in disease models. This method could also test potential drugs that aim to reduce harmful NET production, which could lead to the identification of therapies for many different diseases.This work was funded by OPTIMA, Wellcome Trust and Medical Research Council. Read the full paper in Journal of Inflammation Publication date 10 Mar, 2026
