Stem cells use “first aid kits” to repair damage
Neural stem cells – master cells that can develop into any type of nerve cell – are able to generate mini “first aid kits” and transfer them to immune cells, according to a study published today in Molecular Cell
The team led by SCI PI Dr Stefano Pluchino has shown that stem cells “communicate” with cells by transferring molecules via fluid filled bags called vesicles, helping other cells to modify the damaging immune response around them.
Stem cells hold great promise as a means of repairing cells in conditions such as multiple sclerosis, stroke or injuries of the spinal cord because they have the ability to develop into almost any cell type. Now, new research shows that stem cell therapy can also work through a mechanism other than cell replacement.
Although scientists have speculated that stem cells might act rather like drugs – in sensing signals, moving to specific areas of the body and executing complex reactions – this is the first time that a molecular mechanism for this process has been demonstrated. By understanding this process better, researchers can identify ways of maximising the efficiency of stem-cell-based therapies.
Dr Stefano Pluchino said: “These tiny vesicles in stem cells contain molecules like proteins and nucleic acids that stimulate the target cells and help them to survive – they act like mini “first aid kits”.
“Essentially, they mirror how the stem cells respond to an inflammatory environment like that seen during complex neural injuries and diseases, and they pass this ability on to the target cells. We think this helps injured brain cells to repair themselves.”
“Our work highlights a surprising novel role for stem-cell-derived vesicles in propagating responses to the environment,” added Pluchino. “It represents a significant advance in understanding the many levels of interaction between stem cells and the immune system, and a new molecular mechanism to explain how stem-cell therapy works.”
Publication details: Cossetti C, Iraci N, Mercer TR, Leonardi T, Alpi E, Drago D, Alfaro-Cervello C, Saini HK, Davis MP, Schaeffer J, Vega B, Stefanini M, Zhao C, Muller W, Garcia-Verdugo JM, Mathivanan S, Bachi A, Enright AJ, Mattick JS, Pluchino S. Extracellular vesicles from neural stem cells transfer IFN-g via Ifngr1 to activate Stat1 signalling in target cells. Molecular Cell. DOI: http://dx.doi.org/10.1016/j.molcel.2014.08.020