Figure 3. Myeloperoxidase and citrullinated histone H4 co-localize with extracellular DNA in pyocyanin-stimulated NETs.

A) Human neutrophils were seeded on glass coverslips and incubated in the presence of 20 µM pyocyanin for 3 hours. Cells were fixed and stained for MPO (FITC-labeled anti-MPO Ab) and DNA (DAPI). Two independent fields show co-localization of MPO and DNA (one representative experiment, n = 3). B) Citrullinated histone H4 co-localizes with NET DNA structures in pyocyanin-stimulated neutrophils. Adherent neutrophils were treated with 20 µM pyocyanin for 3 hours, then fixed, washed and subjected to anti-citH4 immunostaining and DAPI staining. Two other experiments gave similar data.