Parasitic wasp protein that may interfere with the host immune response. The recombinant protein inhibits trypsin activity and prophenoloxidase (PPO) activation, an enzyme essential for both clotting and insect innate immune responses. It does not inhibit activity of chymotrypsin and protease K, and has no effect on phenoloxidase (PO) activity. Expressed in the venom apparatus. Low transcript levels are also detected in other tissues. Transcripts are not detected at 0 and 1st day post eclosion (dpe), weakly expressed at 2nd and 3rd dpe, reach a peak on the 4th dpe, and then decline gradually until 7th dpe. Belongs to the protease inhibitor I19 family.