Malaria Parasites use DNA-Harbouring Vesicles as a Mechanism to Activate Cytosolic Immune Sensors

Non-coding RNA such as miRNA is contained in exosomes and can play an important role in cell-cell communication (Valadi et al., 2007). To determine whether exosomes secreted from ring-stage iRBCs contain non-coding RNA and/or coding RNA, total RNA was isolated from exosomes and uRBCs vesicles. The RNA content extracted was assessed using a small RNA Bioanalyser assay. Small RNA deep sequencing using the Ion Torrent PGM and 200bp chemistry was performed to obtain an unbiased profile of non-coding RNA contained in exosomes and vesicles secreted from infected and uninfected RBC cultures. Upon mapping to human miRNA, 229 miRNA were found to be abundantly present in all samples, and the most abundant was hsa-miR-451a. Notably, the majority of human miRNA were found to be present at lower levels in iRBCs exosomes compared to uRBC vesicles.Although further studies are required, these findings raise the possibility that parasite exosomes act on different host cells to manipulate their RNA profiles.