Concept of mesenchymal stem cells: bring more insights into functional research of MSC / 中国实验血液学杂志

ABSTRACT

Mesenchymal stem cells have generated great interest among researchers and physicians due to their unique biological characteristics and potential clinical applications. Here, I propose for the first time the concept of a hierarchical system which is composed of all mesenchymal stem cells from post-embryonic subtotipotent stem cells to MSC progenitors. Post-embryonic subtotipotent stem cells are left-over cells during embryonic development and are on the top of the hierarchy. MSC system is a combination of cells that are derived from different stages of embryonic development, possess different differentiation potential and ultimately give rise to cells that share a similar set of phenotypic markers. The concept of MSC system has important implications (1) it entirely explains the three important biological characteristics of MSC stem cell properties of MSC, MSC as components of tissue microenvironment and immunomodulatory functions of MSC. (2) It balances immune responses and tissue metabolism. (3) It could provide tissue-specific stem cells for clinical application with high efficiency and safety. In a word, this concept constitutes an important part of the biological properties of MSC and will help researchers gain better insight into MSC.