from Technology Networks by Anna MacDonald –
Once considered cellular rubbish, exosomes are now known to play important roles in cellular communication. These small messengers are defined as “extracellular vesicles that are released from cells upon fusion of an intermediate endocytic compartment, the multivesicular body, with the plasma membrane.” (Edgar 2016) Although they were first described in 1983, widespread interest in exosomes did not take hold until the last decade, when their roles in a range of biological functions became more apparent.
Seeing exosomes in a new light
In 2007, research by Dr Jan Lotvall demonstrated that contrary to previous belief, exosomes contained not only proteins and lipids, but also RNA. Further research by Dr Johan Skog showed that exosomes released from glioblastoma tumor cells transport mRNA and miRNA to recipient cells. This opened a new avenue of using exosomes as a proxy to study cancer, with the potential to identify individual mutations and personalize treatment via liquid biopsies.
Challenges of exosome isolation
Before exosomes can be analyzed for diagnostic purposes, they must first be detected and isolated from the blood, urine, saliva or other bodily fluid they are residing in.