Methods to Detect Neutrophil Extracellular Traps in Asthma

Neutrophil extracellular traps (NETs)Neutrophil extracellular traps (NETs) have the ability to regulate many aspects of asthma pathology. NETs Neutrophil extracellular traps (NETs) can be detected either in bronchoalveolar lavageBronchoalveolar lavage (BAL) fluids (BALF) or in lung biopsies. Here, we describe methods to quantify NETs Neutrophil extracellular traps (NETs) in BALF, namely the quantification of cell-free DNACell-free DNA, or of myeloperoxidase (MPO)Myeloperoxidase (MPO) or neutrophil elastase (NE)Neutrophil elastase (NE) complexed with cell-free DNACell-free DNA. We also explain how to detect NETs Neutrophil extracellular traps (NETs) in lung biopsies by two distinct techniques. The first technique is based on quantification of the citrullinated form of histone Histones 3 (Cit-H3 Citrullinated histone 3 (Cit-H3) , a specific component of NET) by western blotWestern blots on tissue protein extracts. The second technique is based on the visualization of extracellular structures composed of MPO Myeloperoxidase (MPO) co-localizing with Cit-H3 Citrullinated histone 3 (Cit-H3) in tissue sectionsTissue sections by confocal microscopyConfocal microscopy. Finally, we describe a method allowing for quantification of NET volume in lung sections.