Exosomes are small microvesicles (40–100 nm) that are formed from the endosome togenerate multi-vesicular bodies (MBVs). In mammals, exosomes play a significant role incellular communication. Exosomes have also been reported for salmon and fruit fly buthave not previously been studied in crustaceans. Therefore we undertook to study themin decapods. We chose the hyaline haemocytes of brachyuran crabs, Carcinus maenas and Hyas araneus, because these cells are abundant in haemolymph, are phagocytic and can becultured on glass or plastic surfaces. Furthermore these cells have been observed tocontain MVB-like structures that bear some resemblance to those in mammals thatproduce exosomes. Preliminary results show that highly enriched hyaline cells of both C.maenas and H. araneus, express actin and haemocyanin during 24 h in vitro. The presence ofhaemocyanin subunits is interesting because haemocyanin is a multifunctional proteinthat participates in immunity in crustaceans. As far as we are aware, the present study isthe first to show that hyaline cells from a crustacean secrete this biologically importantprotein. Other proteins were found but we were unable to identify them by massspectroscopy. Treatment of the hyaline cells in vitro with LPS at sub-lethal concentrationsfailed to reveal a change in the flow cytometric scatter plots or in the protein profiles onSDS-PAGE.
|Number of pages||2|
|Publication status||Published - 2010|