The Continued Quest for Pluripotent Adult Stem Cells
Does the adult mammalian body contain naturally pluripotent stem cells, capable for forming any other cell type, given the right stimuli? Over the past twenty years various groups have argued that it does, but none of those scientists have produced evidence that is both compelling and easily replicated. If they had, the entire research community would have quickly jumped onto that bandwagon, just as they did after the discovery of reprogramming as a way to produce induced pluripotent stem cells. Patient-specific pluripotent cells are a highly desirable item, and a cost-effect source would enable many applications in regenerative medicine and tissue engineering. Given this history, I think it appropriate to treat the material here with a healthy degree of skepticism.
A certain cell type can be isolated from different organs in the adult body (i.e., adipose tissue, heart, skin, bone marrow, or skeletal muscle) that can differentiate into ectoderm, mesoderm, and endoderm, providing significant support for the existence of a certain type of small, ubiquitously distributed, universal, vascular-associated, pluripotent stem cell in the adult body (vaPS cells). These vaPS cells fundamentally differ from embryonic stem cells and induced pluripotent stem cells in that the latter possess the necessary genetic guidance that makes them intrinsically pluripotent. In contrast, vaPS cells do not have this intrinsic genetic guidance. Nevertheless, they are able to differentiate into somatic cells of all three lineages under guidance of the microenvironment they are located in, independent from the original tissue or organ that they are derived from.
These vaPS cells are of high relevance for clinical application because they are contained in unmodified, autologous, adipose-derived regenerative cells (UA-ADRCs). The latter can be obtained from and re-applied to the same patient at the point of care, without the need for further processing, manipulation, and culturing. These findings as well as various clinical examples presented in this paper demonstrate the potential of UA-ADRCs for enabling an entirely new generation of medicine for the benefit of patients and healthcare systems.
As with any medical innovation, the scientific and medical community interested in these novel therapies needs to develop sound clinical evidence to further show safety and efficacy of cell-based therapies. Our understanding of the mechanism of actions and potential benefit of stem cell therapy has increased enormously over the past decade and we hope that there is now enough data to convince others to embark on scientifically designed clinical studies that will provide the necessary objective evidence.