CHAPTER 9: Harnessing stem cell secretome towards cell-free therapeutic strategies

Recent years have observed the development of stem cell therapy, which appeared as promising treatment strategies for various disease conditions. Cell therapies employ stem cells, or cells grown from stem cells, to replace or rejuvenate damaged tissue. Numerous findings have suggested a significant therapeutic advantage with the utilization of cell therapeutic approaches in various neurological disorders including amyotrophic lateral sclerosis, various heart disorders involving endstage ischaemic heart diseases, myocardial infarction, or preventing vascular restenosis. Various bone fractures are also reported to benefit from cell therapy including osteogenesis imperfecta. Nonetheless, cell therapy has its drawbacks, which include the risk of tumorigenesis or immune rejection. The therapy also faces ethical and political controversies besides scientific challenges. Consequently, efforts are made towards the development of stem cell secretome which are the secreted factors produced by the stem cells that are responsible for mediating and modulating stem cells effects in the disease condition. The secretome holds various added advantages: it can be manufactured, freeze-dried, packaged, and transported more easily which is some of the numerous advantages of using secretome over the use of stem cells. Besides, as secretome is free from cells, there is no need to match the donors and recipients to avoid the risk of rejection. For that reason, stem cell-derived secretome is a promising possibility to be used as pharmaceuticals for regenerative medicine. Up till now, there have have been limited clinical trials utilizing secretome in certain disease conditions.