Characterization of Mesenchymal Stromal Cells for Musculoskeletal Disorders and Regenerative Medicine

Abstract

Recently, mesenchymal stromal cells (MSC) have come increasingly into focus as a therapeutic option for bone pathologies and regenerative medicine. While human MSCs have been extensively characterized and standardized, ovine MSCs are poorly understood. The current study reports a direct systematic comparison of human and ovine MSCs from three corresponding sources under the same conditions. All MSCs showed solid growth behavior and potent immunomodulatory capacity. In addition, common positive and negative surface markers were identified. Both human and ovine MSCs showed strong osteogenic potential.<br /> Furthermore, the aim of this study was to isolate and characterize MSCs from the vertebral body of healthy non-osteoporotic and osteoporotic patients as the role of MSCs in osteoporosis is not fully understood. Isolated MSCs were characterized by their trilineage differentiation, surface marker expression, proliferation behavior, and immunomodulatory capacity. MSCs from both healthy and osteoporotic patients showed common morphology, proliferation behavior, expressed the typical MSC surface markers and possessed immunomodulatory capacity. Both groups demonstrated solid trilineage differentiation potential; osteogenic differentiation was further assessed by additional read outs such as optical density (OD) and free phosphate ion release.<br /> Moreover, MSCs harvested from different tissues of the same donor have been shown to exhibit different phenotypes characterized by different cellular functionalities. In this study, we investigated the proteomic and functional properties of human bone marrow-derived MSCs (hBM-MSC) harvested either as aspirate or bone chip. Both MSC populations were profiled according to MSC markers defined by the International Society for Cellular Therapy (ISCT). hBM-MSCs derived from aspirate cultures demonstrated significantly higher osteogenic differentiation potential than MSCs grown from bone chip.<br /> The key findings shown of this report reveal the utility of ovine MSCs in preclinical studies for MSC-based therapies. Furthermore, MSCs derived from vertebral body of osteoporotic patients were not impaired and possessed full osteogenic potential compared with MSCs from non-osteoporotic patients. Moreover, different harvesting techniques indicate the need for future standardized harvesting, processing, and phenotyping procedures to achieve better comparability in the MSC field.