Exosomes are extracellular nanovesicles that mediate a number of cellular processes, including intracellular signalling. There are many published examples of exosome-exosome dimers; however, their relevance has not been explored. Here, researchers from Ben-Gurion University of the Negev propose that cells release exosomes to physically interact with incoming exosomes, forming dimers that they hypothesize attenuate incoming exosome-mediated signalling. The researchers discuss experiments to test this hypothesis and potential relevance in health and disease.
Representative physical exosome:exosome interaction by TEM analysis
Typically, exosomes isolated from conditioned media of cells appearas round vesicles of heterogeneous sizes, ranging from 30 to 150 nm. Physical exosome:exosome interactions lead to changes in exosome shape. (A) Non-Pigmented Cilliary Epithelium (NPCE): Upon interaction, the round single exosomes become more flattened, with relatively a contact areabetween the interacting exosomes. (B) TM-123: On the right side, three flattened exosome:exosome interactions can be observed (▲); non-interact-ing exosomes are presented (*). Non-pigmented ciliary epithelium cell and TM-123-derived exosomes were extracted by ultracentrifugation,suspended in 0.1 M PBS, pH 7.2. PictureAandBwas generated by TEM.