The benefits of most first generation stem cell therapies, in which the overwhelming majority of transplanted cells die fairly rapidly, appear to be mediated by the signals briefly generated by those cells. A sizable portion of the signaling between cells is carried by extracellular vesicles such as exosomes, tiny membrane-wrapped packages of molecules. Given these two points, why not skip the cells in favor of delivering exosomes? This is an expanding area of activity in the regenerative medicine community. Some initiatives, such as the one noted here, have advanced to animal studies - human trials will not be so very many years away.
As regenerative research and development evolves away from the standard practice of the stem cell medicine of the past two decades, the future appears to involve a split of the community into two broad paths. The first path is as described above, to isolate the signals that are important in spurring regeneration, and thus gain control over the behavior of native cells. The second is to solve the problem of transplanted cells dying rather than thriving to undertake useful work. Progress is being made on this front in the form of tissue patches: rather than delivering cells haphazardly, researchers first build a structured pseudo-tissue patch of cells and scaffolding, closer in form to the native tissue. This makes the cells much more resilient and ready to integrate. The next decade in this field will see important advances in the ability to treat many degenerative conditions, I believe.
ArunA Biomedical today announced the publication of data demonstrating that neural stem cell-derived extracellular vesicles (NSC EVs) improved tissue and functional recovery in pigs following ischemic stroke. This is the first ever study to evaluate the therapeutic potential of human NSC EVs in a large animal model representative of the human brain. The neural-derived exosomes, a form of EVs, are a new class of cell-free biologics and cell-mediated drug delivery systems to treat central nervous system and neurodegenerative disorders.
"This study, coupled with our previously published studies focused on a mouse model, represents the first time that a company demonstrated proof-of-concept of the therapeutic potential of extracellular vesicles in two divergent animal species and two stroke types - embolic and ischemic." This is the third study recently completed by ArunA, the first two of which demonstrated improved outcomes in middle-aged and aged mice following embolic stroke.
Study results showed NSC EV treatment: was neuroprotective; eliminated intracranial hemorrhage in ischemic lesions; improved behavior and mobility; decreased cerebral infarct volume and brain swelling; and led to significant improvements at the tissue and functional levels.