Do Media Extracellular Vesicles and Extracellular Vesicles Bound to the Extracellular Matrix Represent Distinct Types of Vesicles?

Abstract

Mineralization-competent cells, including hypertrophic chondrocytes, mature osteoblasts, and osteogenic-differentiated smooth muscle cells secrete media extracellular vesicles (media vesicles) and extracellular vesicles bound to the extracellular matrix (matrix vesicles). Media vesicles are purified directly from the extracellular medium. On the other hand, matrix vesicles are purified after discarding the extracellular medium and subjecting the cells embedded in the extracellular matrix or bone or cartilage tissues to an enzymatic treatment. Several pieces of experimental evidence indicated that matrix vesicles and media vesicles isolated from the same types of mineralizing cells have distinct lipid and protein composition as well as functions. These findings support the view that matrix vesicles and media vesicles released by mineralizing cells have different functions in mineralized tissues due to their location, which is anchored to the extracellular matrix versus free-floating.

Unlocking The Potential of Extracellular Vesicles for Therapeutic and Diagnostic Application

“…This process involves the inward budding of the endosomal membrane, leading to the sequestration of cytoplasmic contents into ILVs. [30][31][32] • Cargo Sorting: Various mechanisms, including the endosomal sorting complexes required for transport (ESCRT) machinery, tetraspanins, and lipid microdomains, are involved in sorting specific cargo into ILVs. ESCRT complexes help recruit ubiquitinated proteins to the endosomal membrane for incorporation into ILVs.…”