Project description:Ex vivo monitored human CD34+ stem cells (SCs) injected into myocardium scar tissue have shown real benefits for the recovery of patients with myocardial infarctions. They have been used previously in clinical trials with hopeful results and are expected to be promising for cardiac regenerative medicine following severe acute myocardial infarctions. However, some debates on their potential efficacy in cardiac regenerative therapies remain to be clarified. To elucidate the levels of CD34+ SCs implication and contribution in cardiac regeneration, better identification of the main regulators, pathways, and genes involved in their potential cardiovascular differentiation and paracrine secretion needs to be determined. We first developed a protocol thought to commit human CD34+ SCs purified from cord blood toward an early cardiovascular lineage. Then, by using a microarray-based approach, we followed their gene expression during differentiation. We compared the transcriptome of undifferentiated CD34+ cells to those induced at two stages of differentiation (i.e., day 3 and day 14), with human cardiomyocyte progenitor cells (CMPCs), as well as cardiomyocytes as controls. Interestingly, in the treated cells we observed an increase in the expressions of the main regulators usually present in cardiovascular cells. We identified cell surface markers of the cardiac mesoderm, such as kinase insert domain receptor (KDR) and the cardiogenic surface receptor Frizzled 4 (FZD4), induced in the differentiated cells in comparison to undifferentiated CD34+ cells. The Wnt and TGF- pathways appeared to be involved in this activation. This study underlined the real capacity of effectively stimulated CD34+ SCs to express cardiac markers and, once induced, allowed the identification of markers that are known to be involved in vascular and early cardiogenesis, demonstrating their potential priming towards cardiovascular cells. These findings could complement their paracrine positive effects known in cell therapy for heart disease and may help improve the efficacy and safety of using ex vivo expanded CD34+ SCs.
Project description:Ex vivo monitored human CD34+ stem cells (SCs) injected into myocardium scar tissue have shown real benefits for the recovery of patients with myocardial infarctions. They have been used previously in clinical trials with hopeful results and are expected to be promising for cardiac regenerative medicine following severe acute myocardial infarctions. However, some debates on their potential efficacy in cardiac regenerative therapies remain to be clarified. To elucidate the levels of CD34+ SC implication and contribution in cardiac regeneration, better identification of the main regulators, pathways, and genes involved in their potential cardiovascular differentiation and paracrine secretion needs to be determined. We first developed a protocol thought to commit human CD34+ SCs purified from cord blood toward an early cardiovascular lineage. Then, by using a microarray-based approach, we followed their gene expression during differentiation. We compared the transcriptome of undifferentiated CD34+ cells to those induced at two stages of differentiation (i.e., day three and day fourteen), with human cardiomyocyte progenitor cells (CMPCs), as well as cardiomyocytes as controls. Interestingly, in the treated cells, we observed an increase in the expressions of the main regulators usually present in cardiovascular cells. We identified cell surface markers of the cardiac mesoderm, such as kinase insert domain receptor (KDR) and the cardiogenic surface receptor Frizzled 4 (FZD4), induced in the differentiated cells in comparison to undifferentiated CD34+ cells. The Wnt and TGF-β pathways appeared to be involved in this activation. This study underlined the real capacity of effectively stimulated CD34+ SCs to express cardiac markers and, once induced, allowed the identification of markers that are known to be involved in vascular and early cardiogenesis, demonstrating their potential priming towards cardiovascular cells. These findings could complement their paracrine positive effects known in cell therapy for heart disease and may help improve the efficacy and safety of using ex vivo expanded CD34+ SCs.
Project description:The comparative characterization of hematopoietic stem cells from healthy stem cell donors and patients with acute myeloid leukemia on a proteome level has the potential to reveal differentially regulated proteins which might be candidates for specific immunotherapy target molecules. Exemplarily, we analyzed the proteome of the cytosolic and the membrane fraction of CD34 and CD123 co-expressing FACS-sorted leukemic progenitors from five patients with acute myeloid leukemia employing mass spectrometry. As a reference, CD34+CD123+ normal hematopoietic progenitor cells from five healthy stem cell donors were analyzed. In this TMT 10-plex labeling based approach 2068 proteins were identified with 256 proteins differentially regulated in one or both cellular compartments. This study demonstrates the feasibility of a mass spectrometry based proteomic approach to detect differentially expressed proteins in two compartment fractions of leukemic stem cells as compared to their healthy stem cell counterparts.
Project description:The label-free quantitative proteome was generated for 42 primary AML patient samples enriched for CD34+ cells (or mononuclear cells in the case of NPMcyt sameples) and as controls 6 mobilized peripheral blood CD34+ cells were included. Furthermore, 6 AML cell lines were included, and also primary mesenchymal stem cells grown under normaoxia or hypoxia were included.
Project description:Gene expression profiles of CD34+CD38- stem cells and more differentiated CD34+CD38+ progenitor cells were compared. Comparison of expression profiles of hematopoietic stem cells from fetal liver, umbilical cord blood, bone marrow and mobilized pheripheral blood allowed us to identify a unique set of genes with conserved expression during ontogeny. Keywords: Cell type comparison
Project description:LincRNA expression profiles of human embryonic stem cells, CD34+ cells, and CD34+ derived induced pluripotent stem cells Total RNA was extracted from human ESCs, CD34+ cells, and CD34+ derived iPSC lines, then hybridized to Nimblegen tiling array GPL8792; Human lincRNA 391k Tiling Array V2
Project description:Activated T cells inhibit neurogenesis in adult animal brain and cultured human fetal neural stem cells (NSC). However, the role of inhibition of neurogenesis in human neuroinflammatory diseases is still uncertain because of the difficulty in obtaining adult NSC from patients. Recent developments in cell reprogramming suggest that NSC may be derived directly from adult fibroblasts. We generated NSC from adult human peripheral CD34+ cells by transfecting the cells with Sendai virus constructs containing Sox-2, Oct3/4, C-MyC and Klf-4. The derived NSC could be differentiated to astroglia and action potential firing neurons. Co-culturing NSC with activated autologous T cells or treatment with recombinant granzyme B caused inhibition of neurogenesis as indicated by decreased NSC proliferation and neuronal differentiation. Thus, we have established a unique autologous in vitro model to study the pathophysiology of neuroinflammatory diseases that has potential for usage in personalized medicine. 11 Human samples from 7 sources representing 4 different cell types: 2 CD34 (CD34+ cells purified from adult peripheral blood), 3 iNS (induced Neural Stem Cells derived directly from CD34+ cells), 2 iNS derived from iPSC (Neural Stem cells differentiated from induced Pluripotent Stem Cells from CD34+ cells), 4 NPC (human primary cultured neural progenitor cells)