1.2. Terminology

Due to the lack of a particularly unique MSCs function, they have been termed 'mesenchymal stem cells' or interchangeably 'mesenchymal stromal cells', 'BM (bone marrow) stromal cells' and 'marrow stromal cells'. MSCs are usually identified by mere plastic adherence and by their morphological appearance, such as the fibroblastoid phenotype. This procedure leads to a diverse population containing both single stem cell-like cells and progenitor cells having various lineage commitment. Compared to hematopoietic stem cells (HSCs), which have been proven to repopulate the bone marrow and give all blood types, and embryonic stem cells (ESCs) which after re-injection into early embryos, were proven to participate in embryonic development of all tissues; MSCs have no established in vivo tests [3].
