Search results for " progenitor cells."
showing 6 items of 56 documents
Stem cell populations in the heart and the role of Isl1 positive cells
2013
Cardiac progenitor cells are multipotent stem cells isolated from both embryonic and adult hearts in several species and are able to differentiate at least into smooth muscle cells, endothelial cells and cardiomyocytes. The embryonic origin of these cells has not yet been demonstrated, but it has been suggested that these cells may derive from the first and secondary heart fields and from the neural crest. In the last decade, two diffe-rent populations of cardiac progenitor or stem cells have been identified and isolated, i.e., the Islet1 positive (Isl1+) and c-Kit positive (c-Kit+)/Stem Cell Antigen-1 positive (Sca-1+) cells. Until 2012, these two populations have been considered two separ…
Erythropoietin and the heart: physiological effects and the therapeutic perspective.
2014
Erythropoietin (Epo) has been thought to act exclusively on erythroid progenitor cells. The identification of Epo receptor (EpoR) in non-haematopoietic cells and tissues including neurons, astrocytes, microglia, immune cells, cancer cell lines, endothelial cells, bone marrow stromal cells, as well as cells of myocardium, reproductive system, gastrointestinal tract, kidney, pancreas and skeletal muscle indicates that Epo has pleiotropic actions. Epo shows signals through protein kinases, anti-apoptotic proteins and transcription factors. In light of interest of administering recombinant human erythropoietin (rhEpo) and its analogues for limiting infarct size and left ventricular (LV) remodel…
Signaling through BMPR-IA regulates quiescence and long-term activity of neural stem cells in the adult hippocampus.
2010
SummaryNeural stem cells (NSCs) in the adult hippocampus divide infrequently, and the molecules that modulate their quiescence are largely unknown. Here, we show that bone morphogenetic protein (BMP) signaling is active in hippocampal NSCs, downstream of BMPR-IA. BMPs reversibly diminish proliferation of cultured NSCs while maintaining their undifferentiated state. In vivo, acute blockade of BMP signaling in the hippocampus by intracerebral infusion of Noggin first recruits quiescent NSCs into the cycle and increases neurogenesis; subsequently, it leads to decreased stem cell division and depletion of precursors and newborn neurons. Consistently, selective ablation of Bmpr1a in hippocampal …
Role of PRRs (TLR2 and Dectin-1) in hematopoietic stem and progenitor cell differentiation: implications in protection against Candida albicans infec…
2020
Detection of infection by hematopoietic stem and progenitor cells (HSPCs) is essential to replace myeloid cells consumed during the immune response. HSPCs express some functional pattern recognition receptors involved in the recognition of Candida albicans. In this context, our group has previously demonstrated that C. albicans yeasts induce proliferation and differentiation of HSPCs via TLR2 and Dectin-1. In the present PhD thesis, we used in vitro and ex vivo models of HSPC differentiation to investigate the functional consequences for mature myeloid cells of exposure of HSPCs to PAMPs or C. albicans yeasts. In vitro experiments show that murine HSPCs continuously exposed to TLR2 or TLR4 …
Rat Cardiac progenitor cells and their application in cell therapy
2015
cells and the subsequent heart failure. When the pharmacological approach no longer complies with the disease evolution, organ transplantation appears to be the only treatment able to rescue the patient life. Cell therapy promises to be clinically efficient and would allow circumventing many limitations of organ transplantation, such as organ low availability, major surgical procedures, high costs and longterm immunosuppression [1]. We designed porous Poly-Lactic Acid (PLLA) and Fibroin scaffolds to deliver CPCs in the heart, we isolated and characterized CPCs for the expression of c-Kit, MDR-1 and Sca-1 by flow cytometry, we tested their degree of differentiation in vitro studying the expr…
Role of hematopoietic stem and progenitor cells in training immunity against infection
2022
During an infection, haematopoiesis is altered to increase the output of mature myeloid cells to fight off the pathogen. It has been demonstrated that the detection of pattern recognition receptor agonists by hematopoietic stem and progenitor cells (HSPCs) induces their differentiation towards mature myeloid cells with modified phenotypes. In the present PhD thesis, we show that an in vitro transient exposure of HSPCs to live Candida albicans cells is sufficient to induce a trained phenotype of the macrophages they produce in a dectin-1- and TLR2-dependent manner. Additionally, we use an HSPC transplantation mouse model to demonstrate that the direct interaction of β-glucans and their recep…