Fig. 7
From: Drosophila innate immunity: regional and functional specialization of prophenoloxidases
Phenoloxidase activity in PPO mutant larvae upon wasp infestation as revealed by heat treatment. Representative photos showing unchallenged larvae (a) and larvae infested by Leptopilina boulardi parasitoid wasps after heat treatment (b). Black dots on the cuticle correspond to melanized crystal cells due to PPO2 activity (black arrows, absent in PPO2 mutants). Large black patches correspond to melanized lamellocytes due to PPO3 activity (red arrows, absent in PPO3 mutants). Knot Col-1 larvae have no lamellocytes [28]