A novel cell-based strategy based on MHCI/CD90 expression levels for highly proliferative MSC identification

Background & Aim Mesenchymal stromal cells (MSCs) are of clinical interest because of their validated safety profile and their tremendous biological properties. Nonetheless, variable clinical outcomes have been reported in the literature. Non-reproducible results are attributed in part to the cellular heterogeneity of MSCs, which makes consistent conclusions about MSC therapeutic potential difficult. The identification of new characteristics aiming to select homogeneous and functional MSCs batches is a real challenge to spread this therapeutic approach. This is particularly important for complex tissue sources like placenta. Methods, Results & Conclusion Canine placenta-derived MSCs (P-MSC) populations were isolated from 18 placentas collected at full-term and evaluated according to the ISCT minimal criteria, including morphological assessment, phenotypic evaluation, immunomodulatory properties and in vitro differentiation ability. No significant difference was found. Nonetheless, dynamic variations of the expression levels of the CD90 and MHCI markers were reported among the cellular populations during the cell passages. In particular, our data showed that the MHCIlow/CD90high sub-population display high proliferative activity, along with high chondrogenic differentiation ability. These results suggest that a better characterization of the MSCs bulk populations, based on a multiparametric data evaluation may help to standardize the cellular products. This could help to respond to industrial challenges for drug development