BACKGROUND AND OBJECTIVES: Cellular therapies using Mesenchymal Stem Cells (MSCs) represent a promising approach for the treatment of degenerative diseases, in particular for mesengenic tissue regeneration. However, before the approval of clinical trials in humans, in vitro studies must be performed aimed at investigating MSCs' biology and the mechanisms regulating their proliferation and differentiation abilities. Besides studies on human MSCs (hMSCs), MSCs derived from rodents have been the most used cellular type for in vitro studies. Nevertheless, the transfer of the results obtained using animal MSCs to hMSCs has been hindered by the limited knowledge regarding the similarities existing between cells of different origins. Aim of this paper is to highlight similarities and differences and to clarify the sometimes reported different results obtained using these cells. METHODS AND RESULTS: We compare the differentiation ability into mesengenic lineages of rat and human MSCs cultured in their standard conditions. Our results describe in which way the source from which MSCs are derived affects their differentiation potential, depending on the mesengenic lineage considered. For osteogenic and chondrogenic lineages, the main difference between human and rat MSCs is represented by differentiation time, while for adipogenesis hMSCs have a greater differentiation potential. CONCLUSIONS: These results on the one hand suggest to carefully evaluate the transfer of results obtained with animal MSCs, on the other hand they offer a clue to better apply MSCs into clinical practice.
Adipogenesis ; Animals ; Biology ; Bone Marrow* ; Hand ; Humans ; Mesenchymal Stromal Cells* ; Rats* ; Regeneration ; Rodentia

Background and Objectives: Transplantation of pancreatic islets is an intriguing new therapeutic option to face the worldwide spread problem of Type-I diabetes. Currently, its clinical use is limited by several problems, mainly based on the high number of islets required to restore normoglycaemia and by the low survival of the transplanted tissue. A promising attempt to overcome the limits to such an approach was represented by the use of Mesenchymal Stem Cells (MSC). Despite the encouraging results obtained with murine-derived MSC, little is still known about their protective mechanisms. The aim of the present study was to verify the effectiveness, (besides murine MSC), of clinically relevant human-derived MSC (hMSC) on protecting pancreatic islets, thus also shedding light on the putative differences between MSC of different origin. Methods: and Results: Threefold kinds of co-cultures were therefore in vitro set up (direct, indirect and mixed), to analyze the hMSC effect on pancreatic islet survival and function and to study the putative mechanisms involved. Although in a different way with respect to murine MSC, also human derived cells demonstrated to be effective on protecting pancreatic islet survival. This effect could be due to the release of some trophic factors, such as VEGF and Il-6, and by the reduction of inflammatory cytokine TNF-α. Conclusions Therefore, hMSC confirmed their great clinical potential to improve the feasibility of pancreatic islet transplantation therapy against diabetes.