Li Li1, Prashant Kumar Jaiswal2, Georges Makhoul1, Rishi Jurakhan1, Kaviyanka Selvasandran1, Khalid Ridwan1, Renzo Cecere3. 1. Division of Experimental Surgery, McGill University, Montreal, Quebec, Canada. 2. Division of Cardiac Surgery, McGill University Health Centre, Montreal, Quebec, Canada. 3. Division of Experimental Surgery, McGill University, Montreal, Quebec, Canada; Division of Cardiac Surgery, McGill University Health Centre, Montreal, Quebec, Canada. Electronic address: renzo.cecere@muhc.mcgill.ca.
Abstract
OBJECTIVES: For more than a decade, stem cells isolated from different tissues have been evaluated in cell therapy. Among them, the human bone marrow-derived mesenchymal stem cells (hBM-MSCs) were investigated extensively in the treatment of myocardial infarction. Recently, the human placenta-derived mesenchymal stem cells (hPD-MSCs), which are readily available from a biological waste, appear to be a viable alternative to hBM-MSCs. METHODS: C-X-C chemokine receptor type 4 (CXCR4) gene expression and localization were detected and validated in hPD-MSCs and hBM-MSCs via polymerase chain reaction and immunofluorescence. Subsequently, cell culture conditions for CXCR4 expression were optimized in stromal-derived factor-1 alpha (SDF1-α), glucose, and cobalt chloride (CoCl2) by the use of cell viability, proliferation, and migration assays. To elucidate the cell signaling pathway, protein expression of CXCR4, hypoxia-inducible factor-1α, interleukin-6, Akt, and extracellular signal-regulated kinase were analyzed by Western blot. CXCR4-positive cells were sorted and analyzed by florescence-activated cell sorting. RESULTS: CXCR4 was expressed on both hPD-MSCs and hBM-MSCs at the basal level. HPD-MSCs were shown to have a greater sensitivity to SDF-1α-dependent cell migration compared with hBM-MSCs. In addition, CXCR4 expression was significantly greater in both hPD-MSCs and hBM-MSCs with SDF-1α or CoCl2-induced hypoxia treatment. However, CXCR4+ hPD-MSCs population increased by 10-fold in CoCl2-induced hypoxia. In contrast, only a 2-fold increase was observed in the CXCR4+ hBM-MSCs population in similar conditions. After CoCl2-induced hypoxia, the CXCR4/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase signaling pathway was activated prominently in hPD-MSCs, whereas in hBM-MSCs, the CXCR4/phosphatidylinositol 3-kinase/Akt pathway was triggered. CONCLUSIONS: Our current results suggest that hPD-MSCs could represent a viable and effective alternative to hBM-MSCs for translational studies in cardiocellular repair.
OBJECTIVES: For more than a decade, stem cells isolated from different tissues have been evaluated in cell therapy. Among them, the human bone marrow-derived mesenchymal stem cells (hBM-MSCs) were investigated extensively in the treatment of myocardial infarction. Recently, the human placenta-derived mesenchymal stem cells (hPD-MSCs), which are readily available from a biological waste, appear to be a viable alternative to hBM-MSCs. METHODS:C-X-C chemokine receptor type 4 (CXCR4) gene expression and localization were detected and validated in hPD-MSCs and hBM-MSCs via polymerase chain reaction and immunofluorescence. Subsequently, cell culture conditions for CXCR4 expression were optimized in stromal-derived factor-1 alpha (SDF1-α), glucose, and cobalt chloride (CoCl2) by the use of cell viability, proliferation, and migration assays. To elucidate the cell signaling pathway, protein expression of CXCR4, hypoxia-inducible factor-1α, interleukin-6, Akt, and extracellular signal-regulated kinase were analyzed by Western blot. CXCR4-positive cells were sorted and analyzed by florescence-activated cell sorting. RESULTS:CXCR4 was expressed on both hPD-MSCs and hBM-MSCs at the basal level. HPD-MSCs were shown to have a greater sensitivity to SDF-1α-dependent cell migration compared with hBM-MSCs. In addition, CXCR4 expression was significantly greater in both hPD-MSCs and hBM-MSCs with SDF-1α or CoCl2-induced hypoxia treatment. However, CXCR4+ hPD-MSCs population increased by 10-fold in CoCl2-induced hypoxia. In contrast, only a 2-fold increase was observed in the CXCR4+ hBM-MSCs population in similar conditions. After CoCl2-induced hypoxia, the CXCR4/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase signaling pathway was activated prominently in hPD-MSCs, whereas in hBM-MSCs, the CXCR4/phosphatidylinositol 3-kinase/Akt pathway was triggered. CONCLUSIONS: Our current results suggest that hPD-MSCs could represent a viable and effective alternative to hBM-MSCs for translational studies in cardiocellular repair.