Abstract

Extracellular Vesicles as Biologic Modifiers

Peter Quesenberry, Professor, The Warren Alpert Medical School of Brown University

Extracellular vesicles are produced by essentially all tissues. Their nature is predicated by the nature of the originator cells, the treatment of the originator cells, the nature of the target cells and the type of initial vesicle separation. Vesicles have been shown to have deleterious or beneficial effects in different settings. If the vesicles derive from damaged or diseased tissue the effects are generally to make the situation worse, this is seen in cancer and pulmonary hypertension models. However, if the vesicles derive from normal tissues or mesenchymal stem cells healing effects are generally seen. Based on a number of studies it would appear that initial biologic effects of vesicles are due to transfer of mRNA and transcriptional regulators but long term effects are due to transcriptional modifications. Different studies have shown reversion of renal injury and radiation induced marrow injury with mesenchymal stem cell derived vesicles. The vesicles largely consist of exosomes and microvesicles which may be differently active in different models. The functional effects are stable on long term storage in 10% DMSO. Overall, administration of extracellular vesicles represent promising therapeutic approaches for a number of tissue injuries or diseases.