Purification of recombinant AnxA1 and SAnxA1 by chromatography. After cloning in the pGEX-6P-1 vector, in frame with GST, GST-tag was used to purify AnxA1 and SAnxA1 on a Glutathione Sepharose 4B column. (A) Coomassie blue-stained gel of recombinant GST-AnxA1 and GST-SAnxA1 expressed in BL21 cells after IPTG treatment. (B) Coomassie blue-stained gel of recombinant AnxA1 and SAnxA1 recovered after GST tag removal, using PreScission Protease. Immunoblot (IB) of purified recombinant AnxA1 and SAnxA1, using a specific anti-AnxA1 antibody. (C) Western blotting analysis of AnxA1 and SAnxA1 cleavage by recombinant PR3 and PMN lysates, after incubation for 30 minutes at 37°C. Results are representative of 3 distinct preparations and experiments.