Immune response in hemocytes, guts, and pelts of Aedes aegypti after blood feeding and hormone injection

Hemocytes in mosquitoes and other insects provide defense against potential pathogens through both cellular responses like phagocytosis and production of effector molecules like antimicrobial peptides (AMPs), complement-like proteins, and products generated by the phenoloxidase cascade. We thus reasoned that blood feeding and the associated release of insulin-like peptide 3 (ILP3) could be restricted to increasing hemocyte abundance or could both stimulate proliferation and prime one or more effector responses by affecting the expression of immune genes. We therefore conducted an RNA-seq analysis that compared expression of known Ae. aegypti immune genes in hemocytes, midguts, and fat bodies from 24 h PBM intact females, 24 h PBM decapitated females that had been injected with ILP3, and age-matched NBF females. We additionally sequenced the midguts and fat bodies for 24 h PBM decapitated females that had been injected with ovary ecdysteroidogenic hormone (OEH) and 20-hydroxyecdysone (20E) as well as intact females injected with heat killed E. coli to better understand the full immune response after blood feeding.