Relaying Cellular Communication in Biology

Michael T McManus, Ph.D.

Exosomes—nanoscale extracellular vesicles secreted by nearly all cell types — play a central role in intercellular communication by delivering diverse molecular cargo to recipient cells. Our lab has developed an RNA-based exosome platform that uses transferable molecular barcodes to trace cellular interactions. This includes Relay, a deep-sequencing-based technology for mapping direct cell-cell contacts, and ExoRelay, which leverages engineered exosomes to non-invasively record cellular behaviors and interaction histories. I will also describe how Relay exosomes can be used to systematically map MHC-presented peptides and identify which T cell receptors bind specific pMHC complexes — advancing our understanding of immune surveillance. Together, these technologies illustrate how engineered exosomes can be transformed into precision tools for probing and ultimately reprogramming complex molecular and cellular interactions.