Figure 4.

The MAPK pathway participates in NET production. (A) Western blot for the phosphorylation of H3Cit, p38 and ERK1/2 in neutrophils pretreated with the inhibitors SB203580 (20 µM/L) or PD98059 (10 µM/L) for 0.5 hours and incubated with IL-8 (50 ng/mL) or the control for 4 hours (n = 3 per group). The protein samples were quantified using densitometry through ImageJ software and normalized. (B) The measurements of extracellular DNA levels indicated the presence of NETs after the above treatment (n = 3 per group). (C) Representative immunofluorescence images of DAPI-labeled DNA and immunolabeled H3Cit and MPO of neutrophils treated as mentioned above (n = 3 per group). The data were expressed as mean ± SD and analyzed using a one-way ANOVA test. *P < 0.05, **P < 0.01.