Mesenchymal Stromal Cell-Derived Extracellular Vesicles Provide Long-Term Survival After Total Body Irradiation Without Additional Hematopoietic Stem Cell Support.

The therapeutic effect of mesenchymal stromal cells (MSC) in tissue regeneration is based mainly on the secretion of bioactive molecules. Here, we report that the radioprotective effect of mouse bone marrow derived mesenchymal stromal cells (mMSC) can be attributed to extracellular vesicles (EV) released from mMSC. The transplantation of mMSC-derived EV into lethally irradiated mice resulted in long-term survival but no improvement in short-term reconstitution of the recipients.