Project description:Derivation of induced smooth muscle cells (iSMC) through direct transdifferentiation of a convenient and expandable primary cell source would open a wide range of prospects for their use in tissue engineering, drug testing, and disease modeling. Hypothesizing that MYOCD as a master regulator of smooth muscle gene expression would facilitate the generation of iSMC, we studied the conversion of human endothelial progenitor cells (EPC) into iSMC through the induced expression of by over-expression of MYOCD. A significant cytoskeletal rearrangement of the EPC resembling that of mesenchymal cells occurred within 3 days post initiation of MYOCD expression. This transition was associated with a downregulation of endothelial cell surface markers (CD31, CD105) as determined by flow cytometry. By day 7, iSMC derivation was evident with a significant upregulation of smooth muscle markers ACTA2, MYH11, TAGLN, and downregulation of CD31 and CDH5 as determined by gene expression analysis. Immunofluorescence revealed expression of MYH11 and ACTA2 and absence of endothelial markers VWF and CD31. By two weeks, microarray gene expression analysis demonstrated a significant similarity between iSMC and umbilical artery SMC (UASMC). The iSMC continued to develop toward the SMC lineage after four weeks of MYOCD induced expression. Microarray gene expression analysis showed an upregulation of molecular pathways associated with smooth muscle contraction and cytoskeletal reorganization in iSMC. Calcium transients were detected in iSMC when stimulated with phenylephrine but not in EPC. Contractility of iSMC was also higher than that of EPC as determined by traction force microscopy. Tissue-engineered blood vessels constructed using iSMC showed functionality with respect to flow- and drug- mediated vasodilation and vasoconstriction. We used microarrays to detail the global programme of gene expression underlying the transdifferentiation of endothelial progenitor cells into smooth muscle cells via the transient induced expression of the transcriptional co factor MYOCD
Project description:We report a novel technique to reprogram human fibroblasts into endothelial and smooth muscle cells using partial iPSC reprogramming and chemically defined media. Using appropriate media conditions for differentiation of human pluripotent cells to CD34+ vascular progenitor cells, we show that temporary expression of pluripotent transcription factors and treatment with chemically-defined media, will induce differentiation of human fibroblasts to CD34+ vascular progenitor cells. Sorted CD34+ cells can then be directed to differentiate into vascular endothelial cells expressing a variety of smooth muscle markers. We have assessed the global DNA methylation (Illumina Infinium HD 450K DNA methylationBeadChips) and transcriptional (Illumina HT12v4 Gene Expression Bead Array) profiles of transdifferentiated endothelial cells and smooth muscle, human embryonic stem cell (hESC) and human induced pluripotent stem cell (hiPSC) differentiated CD34+ angioblasts, hESCs, hiPSC, primary smooth muscle and primary human umbilical vein endothelial cells using microarrays.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:We report a novel technique to reprogram human fibroblasts into endothelial and smooth muscle cells using partial iPSC reprogramming and chemically defined media. Using appropriate media conditions for differentiation of human pluripotent cells to CD34+ vascular progenitor cells, we show that temporary expression of pluripotent transcription factors and treatment with chemically-defined media, will induce differentiation of human fibroblasts to CD34+ vascular progenitor cells. Sorted CD34+ cells can then be directed to differentiate into vascular endothelial cells expressing a variety of smooth muscle markers. We have assessed the global DNA methylation (Illumina Infinium HD 450K DNA methylationBeadChips) and transcriptional (Illumina HT12v3 and HT12v4 Gene Expression Bead Array) profiles of transdifferentiated endothelial cells and smooth muscle, human embryonic stem cell (hESC) and human induced pluripotent stem cell (hiPSC) differentiated CD34+ angioblasts, hESCs, hiPSC, primary smooth muscle and primary human umbilical vein endothelial cells using microarrays.
Project description:Analysis of ex vivo isolated lymphatic endothelial cells from the dermis of patients to define type 2 diabetes-induced changes. Results preveal aberrant dermal lymphangiogenesis and provide insight into its role in the pathogenesis of persistent skin inflammation in type 2 diabetes. The ex vivo dLEC transcriptome reveals a dramatic influence of the T2D environment on multiple molecular and cellular processes, mirroring the phenotypic changes seen in T2D affected skin. The positively and negatively correlated dLEC transcripts directly cohere to prolonged inflammatory periods and reduced infectious resistance of patients´ skin. Further, lymphatic vessels might be involved in tissue remodeling processes during T2D induced skin alterations associated with impaired wound healing and altered dermal architecture. Hence, dermal lymphatic vessels might be directly associated with T2D disease promotion. Global gene expression profile of normal dermal lymphatic endothelial cells (ndLECs) compared to dermal lymphatic endothelial cells derived from type 2 diabetic patients (dLECs).Quadruplicate biological samples were analyzed from human lymphatic endothelial cells (4 x diabetic; 4 x non-diabetic). subsets: 1 disease state set (dLECs), 1 control set (ndLECs)
Project description:The LIM-homeodomain transcription factor ISL1 marks multipotent cardiac progenitors that give rise to cardiac muscle, endothelium, and smooth muscle cells. ISL1+ progenitors can be derived from human pluripotent stem cells, but the inability to efficiently isolate pure populations has limited their characterization. Using a genetic selection strategy, we were able to highly enrich ISL1+ cells derived from human embryonic stem cells. Comparative quantitative proteomic analysis of enriched ISL1+ cells identified ALCAM (CD166) as a surface marker that enabled the isolation of ISL1+ progenitor cells. ALCAM+/ISL1+ progenitors are multipotent and differentiate into cardiomyocytes, endothelial cells, and smooth muscle cells. Transplantation of ALCAM+ progenitors enhances tissue recovery, restores cardiac function and improves angiogenesis through activation of AKT-MAPK signaling in a rat model of myocardial infarction, based on cardiac MRI and histology. Our study establishes a new efficient method for scalable purification of human ISL1+ cardiac precursor cells for therapeutic applications.