11. Summary and conclusion

Mesenchymal stem cells (MSCs) are plastic-adherent, fibroblast-like, multipotent cells found in the human body having the ability to differentiate into different cell types including osteoblasts, adipocytes and chondrocytes. They are normally present in the umbilical cord, adipose tissue, bone marrow but can also be resident in other tissues and are recruited to sites of wound healing as well as growing tumors.

MSCs are a promising candidate for cell-based tissue regeneration that can potentially revolutionize the current pharmaceutical landscape. The extracellular matrix (ECM), adjacent cells and different types of cytokines and growth factors forming MSC niche microenvironment, are critical for their lineage differentiation. Standardized protocols for cell culture, differentiation, expansion and cryopreservation need to be in place. These factors in combination with safely preconditioned and genetically modified MSCs may pave the way for the development of an effective cellular therapy for countless human immune disorders.

Recently, research and basic knowledge of these cells has fast-tracked, both from fundamental and translational perspectives. There have been important discoveries about the available variety of tissue sources. In addition, novel abilities such as immune-modulation together with improved delivery to the selected optimal tissue site has been discovered. However, the molecular fingerprint of MSCs in these contexts remains imprecise and inadequate. Consequently, without this crucial knowledge the progress is difficult in order to determine with precision the MSCs practical developmental potentials.

Overall, the unavoidable propaganda fluctuation that continued for more than 40 years of work on BMSCs did not reduce the novel biological flavor of these cells. Concurrently functioning as stem cells and as cells providing the microenvironment for other stem cells, BMSCs incorporate properties of the "seed" and "soil." As expectations linked to BMSC plasticity are diminishing, these unique properties of BMSCs challenge both biology and medicine in a quite remarkable fashion.
