Stem cells and cell therapy: On the eve of scientific discovery

Cell therapies and stem cells (SCs) have recently become a popular topic. This field of research is cluttered with numerous publications of questionable reliability. Not all methods applied in practice are founded on evidence from research. Although the literature is abundant, there is a gap between the supposed healing properties of SCs associated with their ability to migrate to and engraft on injured tissue, as well as a lack of clear morphological proof. Accordingly, there is a gap between advertising and a part of the professional literature; whereas the former speaks about the rejuvenation of tissues, the latter attributes sometimes questionable therapeutic effects to paracrine or immunomodulating mechanisms and the secretion of cytokines and growth factors. However, SCs are undifferentiated cells; therefore, specific and efficient paracrine function compared to other, more differentiated cells can hardly be expected. In conclusion, it should be noted that the main problem with SCs and cell therapy is commercial influence. The experiences of some foreign countries where attempts have been made to stop the use of unproven treatments, including some stem-cell therapies, should most likely be studied. © 2011 Pleiades Publishing, Ltd.