Stem Cell Reviews and Reports journal gives some articles for free. One of the recent methodological studies, published online – Growth and Differentiation Properties of Mesenchymal Stromal Cell Populations Derived from Whole Human Umbilical Cord.
Some interesting points I’ve picked:
A high number of adherent cells displaying a mainly fibroblast-like morphology as well as the presence of cell surface markers CD44, CD73, CD90 and CD105 can be isolated from whole human UC tissue using an explant culture. This cell isolation procedure is simple, highly reproducible, non-invasive and yields an immunophenotypically homogenous cell population without enzymatic digestion of UC tissue or utilization of additional purification steps associated with blood and endothelial cell elimination.
More importantly, in cell populations collected from whole UC only a small subset of cells carries HLA-I proteins. This finding strongly disagrees with data published by other research groups, which reported that the majority of cells isolated from human UC are positive for HLA-I. This discrepancy raises the question, how the employed in vitro culture conditions, in particular the presence of xenogenic sera, influence the extent of HLA-I expression . We are the first, who generally avoided the use of any xenogenic media supplements during UC cell isolation, expansion and differentiation.
Furthermore, our study demonstrates that cells derived from whole UC tissue, equal to cells harvested from discrete compartments of human UC, display a distinct chondrogenic potential and the capability to differentiate along the adipogenic pathway.
In contrast to adipogenic and chondrogenic differentiation potentials, which are confirmed by several scientific groups, the statements regarding the osteogenic capacity of UC-derived cells are widely different. Whereas some investigators describe an osteogenic potential comparable to bone marrow MSC [55, 56] and even higher , others show that cells collected from human UC are poorly osteogenic and only some of them are capable to undergo osteogenic differentiation [57, 58]. Our data corroborate the last thesis.
As the majority of isolated cells were not able to complete the osteogenic differentiation under conditions traditionally used for the induction of osteogenesis, we currently propose, in accordance with the statement of International Society for Cellular Therapy, to define stem cells harvested from whole UC tissue as multipotent mesenchymal stromal cells.