Factors expressed by MultiStem have the potential to deliver a therapeutic benefit in several ways, such as reducing inflammation, protecting damaged or injured tissue, and enhancing the formation of new blood vessels in regions of ischemic injury. These cells exhibit a drug-like profile in that they act primarily through the production of multiple factors that regulate the immune system, protect damaged or injured cells, promote tissue repair and healing, and the cells are subsequently cleared from the body over time.

Rebalancing the Immune System

When confronted with major injuries or serious infections, the immune system may react in such a way to cause more harm than good. MultiStem cell therapy may act therapeutically by decreasing the activation of the peripheral immune response to the initial injury. This reduces inflammation resulting in less secondary tissue damage and scarring, and allows for accelerated repair processes to begin, potentially improving recovery and outcomes for the patients.

Our research shows that when MultiStem is administered intravenously following acute injury, such as a stroke, a majority of the cells home to the spleen. From there, the cells mitigate the activation of the peripheral immune system in T cells and macrophages in an acute time frame.

MultiStem cells act in several ways to rebalance the immune system. Our data suggests that administering MultiStem cells results in less inflammation, less activation and migration of the peripheral immune system to the site of injury. In essence, the “bad cells” are “turned off” while at the same time, the “good cells” are “turned on”. MultiStem has shown to decrease the adverse results of inflammation, while activating reparative immune cells.

Biomarker analysis shows that inflammatory cytokine levels (molecules associated with immune cell signaling) decrease in the presence of MultiStem cells.

Athersys works with scientific collaborators all over the world to deepen our level of understanding of how our cells work. We have dozens of scientific publications with data supporting our hypothesis on the mechanism of action. Here, Dr. Alice Valentin-Torres discusses the research and findings described in the Scientific Reports by Nature publication supporting the hypothesis of how MAPC® (MultiStem®) modulates immune responses under different clinical conditions.


Valentin-Torres, A., Day, C., Taggart, J.M. et al. Multipotent adult progenitor cells induce regulatory T cells and promote their suppressive phenotype via TGFβ and monocyte-dependent mechanisms. Sci Rep 11, 13549 (2021).