Ep 52 What Makes Dezawa MuseCells® Unique Without Genetic Modification?

Let’s talk today about a distinction that comes up often in stem cell research: the difference between cells that are engineered to become pluripotent, and cells that are simply found that way in the body already.

 

Most of the attention-grabbing stem cell science over the past two decades has centered on induced pluripotent stem cells, or iPSCs, first developed by Shinya Yamanaka. Making an iPSC involves taking an adult cell and introducing specific transcription factors to push it back into an embryonic-like state. It’s a clever workaround for the ethical and supply issues tied to embryonic stem cells, but it introduces its own technical challenges, including the risk that if any of those reprogrammed cells remain undifferentiated after transplant, they can form a type of tumor called a teratoma. Embryonic stem cells carry similar tumorigenicity concerns of their own.

 

Muse cells take a different path entirely. They were first identified in 2010 by Professor Mari Dezawa and colleagues, and they occur naturally in adult tissue, including bone marrow, fat tissue, and peripheral blood. Researchers identify them using a surface marker called SSEA-3, and because they already exist in the body in this state, isolating them is a matter of sorting cells that are already there, rather than reprogramming or engineering anything. No viral vectors, no transcription factor reprogramming, no embryonic tissue involved.

 

That distinction turns out to matter for a few practical reasons researchers care about. First, tumorigenicity: published animal studies to date haven’t shown Muse cells forming teratomas, in contrast to the documented risk associated with iPSCs and embryonic stem cells. Second, manufacturing complexity: because there’s no reprogramming or differentiation-induction step required, the production process is simpler than what’s needed for engineered pluripotent cells. Third, immune compatibility: Muse cells express a marker called HLA-G, which is associated with immune tolerance, similar to mechanisms seen in placental tissue. Researchers have studied whether that property might reduce the need for donor matching or immunosuppressive drugs in certain contexts. And fourth, there’s the homing behavior we’ve covered on this show before, the ability of Muse cells to travel to an injury site through a signaling pathway involving sphingosine-1-phosphate and a receptor called S1PR2, a property not shared by standard mesenchymal stem cells to the same degree.

 

Put together, natural origin, an apparent absence of tumor formation in current studies, and built-in injury homing make Muse cells a distinct subject of study compared to both conventional mesenchymal stem cells and engineered pluripotent cell types. That’s part of why groups like STEMS Health, a Miami Beach-based regenerative medicine practice, keep a close eye on this area of the literature.

 

Thanks for tuning in, and we’ll see you next time.