we first expressed AAa and AAg in a eukaryotic system to investigate whether the proteins could be sulfated in vivo. For this purpose we used insect cells as a model of the Anopheles mosquito. Specifically, codon-optimized sequences encoding AAa and AAg were designed as N-terminal fusions with the honeybee mellitin signal sequence in order to direct the recombinant proteins to the secretion pathway and were expressed in Trichoplusia ni insect cells. Following expression, the cell medium containing the secreted proteins was analyzed by nanoliquid chromatography coupled to tandem mass spectrometry (nanoLC-MS/MS).