Updated project metadata. As marine invertebrates, oysters lack adaptive immunity and employ innate immunity as the front line and lmost the solo defense mechanism to protect them against invaders. Accumulating research achievements demonstrated that exosomes could act as innate immune effectors that contribute to host defense mechanism. To better understand the immune functions of exosomes in Crassostrea gigas against bacterial stimulation, iTRAQ was applied to explore the global protein changes of exosomes in oyster after Staphylococcus aureus and Vibrio splendidus stimulation.