Fig. 2. N-AS-acetylated COX2 produces SPMs.

a Human recombinant COX2 treated in the presence or absence of 500 μM N-AS or aspirin was incubated with AA, EPA, or DHA in presence of human 5-LOX, and then SPM precursors were identified using systematic LC-MS/MS. Representative chromatogram showing the SPM precursors (Top, 15-HETE; Middle, 18-HEPE; Bottom, 17-HDHA). b Human recombinant COX2 treated in the presence of 500 μM N-AS or aspirin was incubated with AA, EPA, or DHA in presence of human 5-LOX. Related MS/MS spectra employed for identification of SPMs. 15R-LXA₄, RvE1, and RvD1. c Quantification of 15R-LXA₄, RvE1, and RvD1 in COX2 WT and COX2 S565A treated with 5-LOX in presence of N-AS, aspirin or not (n = 5–7 independent experiments per group). c One-way analysis of variance, Tukey’s post hoc test. All error bars indicate s.e.m. Source data are provided as a Source data file.