A German research team at the University of Duisburg-Essen has published a study in the latest issue of STEM CELLS Translational Medicine that shows tiny membrane-enclosed structures that travel between cells work as well as adult stem cells to help the brain recover from a stroke.
Extracellular vesicles (EVs), which are small, membrane-enclosed structures that pass between cells, which are also referred to as exosomes, were given to one group of stroke-impaired mice and adult stem cells from bone marrow to another. After monitoring these mice for four weeks, both groups experienced the same degree of neurological repair. Besides promoting brain recovery in the mice, the EVs also down-regulated the post-stroke immune responses and provided long-term neurological protection.
This study could lead to a new clinical treatment for ischemic strokes, since exosomes carry far fewer risks than adult stem cell transplants, according to the co-leaders of this research, neurologist Thorsten Doeppner, and Bernd Giebel, a transfusion medicine specialist.
“We predict that with stringent proof-of-concept strategies, it might be possible to translate this therapy from rodents to humans, since EVs are better suited to clinical use than stem cell transplants,” said Doeppner and Giebel.
Scientists think that EVs carry biological signals between cells and direct a wide range of processes. Exosomes are under a good deal of scientific investigation for the role they could play in cancer, infectious diseases, and neurological disorders.
Other studies have shown that exosome administration can be beneficial after a stroke, but the Duisburg-Essen study is the first to supply evidence through a side-by-side analysis that they act as a key agent in repairing the brain.
“The fact that intravenous EV delivery alone was enough to protect the post-stroke brain and help it recover highlights the clinical potential of EVs in future stroke treatment,” Doeppner and Giebel said.
This study included contributions from ten different researchers from Duisburg-Essen’s Department of Neurology and Institute for Transfusion Medicine. The study was supported by the university, Volkswagen Foundation and German Research Council.
“The current research, combined with the previous demonstration that EVs are well tolerated in men, suggests the potential for using this treatment in conjunction with clot-busting therapies for treatment of stroke,” said Anthony Atala, M.D., editor of STEM CELLS Translational Medicine and Director of the Wake Forest Institute for Regenerative Medicine.