Bone marrow-derived mesenchymal stem cells co-cultured with pancreatic islets display β cell plasticity

Abstract

The direct co-culturing effect of rat bone-marrow-derived mesenchymal stem cells (rBM-MSCs) on the pancreatic-islets (PIs) was studied to obtain functional islet cells. MSCs were isolated from rat bone marrow and cultivated under standard conditions. Following their characterization, the rBM-MSCs were directly (with cell-islet contact) co-cultured with recovered PIs together with the single cell cultures of those cell cultures as a control. The effect of direct co-cultures of rBM-MSCs with the PIs of normal rats was investigated using immunophenotypical and functional methods. The change in the amount of insulin secretion was evaluated as an indicator for differentiation of rBM-MSCs. One approache for in vitro differentiation to achieve reprogramming for differentiation into suitable cell types by changing the microenvironment of the cells to provide signals that might activate metabolic pathways is to use co-cultures with the microenvironment of the specific cells of the desired cell type, tissue/organ extracts, extracellular matrix compounds or biologically absorbable materials. Differentiated rBM-MSCs were found to be immunopositive for the specific insulin-producing cell marker, insulin, but not in undifferentiated rBM-MSCs. The functionality tests by ELISA confirmed that insulin secretion of co-cultured MSCs with islets was higher than that of islets. These evidences indicated that PIs could be regarded as critical components of the stem cell niche, such that MSCs can be differentiated into insulin-producing cells (IPCs). Moreover, direct cell-to-cell contact might provide additional and independent support. This approach would circumvent the need for PI-stem cell co-culture and could potentially facilitate the production of functional IPCs for future clinical applications.

Mesenchymal Stem Cells from the Retropatellar Fat Pad and Peripheral Blood Stimulate ACL Fibroblast Migration, Proliferation, and Collagen Gene Expression

“…The increase in mRNA expression by the ACL fibroblasts here is consistent with previous reports in the literature [4,27], but a new finding in this report is that the co-culture also resulted in an upregulation of the collagen mRNAs in the ADSCs and plastic adherent PBMCs themselves, as shown in the qPCR results after FACS sorting of the co-cultures. This supports our second hypothesis that MSC differentiation can be influenced by the surrounding microenvironment as suggested by Ball [31] and Karaoz [32]. Our findings suggest that MSC-like cells derived from various tissues might be able to adapt and differentiate depending on the surrounding tissue.…”

Protective Effect of Human Mesenchymal Stem Cells on the Survival of Pancreatic Islets

“…The co-transplantation with MSC has been suggested in order to improve the clinical applicability of such a method, but despite the promising results (24)(25)(26), the exact mechanisms by which MSC are able to improve transplantation efficacy have not yet been understood. In addition, the most part of the papers reported in literature deals with murine MSC (14,27,28), which use is inapplicable for clinical practice.…”

“…An explanation to such an observation could be derived by the fact that, while in the direct co-cultures the islets maintained their classical roundish morphology remaining in suspension, in the indirect and mixed co-cultures the islets tended to assume a more elongated shape and to adhere to the Transwell that separated them from the hMSC. Several studies have underlined the importance of maintaining the correct islet structure in order to ensure their functionality, by preserving their phenotype and secretory properties, the islets have to remain in suspension and not to adhere to a substrate (28,32).…”

A Double Mechanism for the Mesenchymal Stem Cells' Positive Effect on Pancreatic Islets

“…MSCs, simply added to the culture, can grow in adhesion to floating pancreatic islets, thus preserving both the tridimensional structure of pancreatic islets (and, therefore, their properties), and the correct culture conditions of MSCs, a basic requisite for maintaining their potential. It is important to maintain pancreatic islets in suspension since, when adherent to a substrate, they lose their particular phenotype and secretion properties [28]–[30]. The validity of this kind of culture has already been demonstrated by Duprez et al [31], but only for a short period of culture.…”