Search results for "Progenitor"
showing 10 items of 355 documents
The differentiation of the serotonergic neurons in the Drosophila ventral nerve cord depends on the combined function of the zinc finger proteins Eag…
1997
ABSTRACT The Drosophila ventral nerve cord (vNC) derives from a stereotyped population of neural stem cells, neuroblasts (NBs), each of which gives rise to a characteristic cell lineage. The mechanisms leading to the specification and differentiation of these lineages are largely unknown. Here we analyse mechanisms leading to cell differentiation within the NB 7-3 lineage. Analogous to the grasshopper, NB 7-3 is the progenitor of the Drosophila vNC serotonergic neurons. The zinc finger protein Eagle (Eg) is expressed in NB 7-3 just after delamination and is present in all NB 7-3 progeny until late stage 17. DiI cell lineage tracing and immunocytochemistry reveal that eg is required for norm…
Silk fibroin scaffolds enhance cell commitment of adult rat cardiac progenitor cells.
2015
The use of three-dimensional (3D) cultures may induce cardiac progenitor cells to synthesize their own extracellular matrix (ECM) and sarcomeric proteins to initiate cardiac differentiation. 3D cultures grown on synthetic scaffolds may favour the implantation and survival of stem cells for cell therapy when pharmacological therapies are not efficient in curing cardiovascular diseases and when organ transplantation remains the only treatment able to rescue the patient’s life. Silk fibroin-based scaffolds may be used to increase cell affinity to biomaterials and may be chemically modified to improve cell adhesion. In the present study, porous, partially orientated and electrospun nanometric n…
Improving vascularization of engineered bone through the generation of pro-angiogenic effects in co-culture systems
2014
One of the major problems with bone tissue engineering is the development of a rapid vascularization after implantation to supply the growing osteoblast cells with the nutrients to grow and survive as well as to remove waste products. It has been demonstrated that capillary-like structures produced in vitro will anastomose rapidly after implantation and become functioning blood vessels. For this reason, in recent years many studies have examined a variety of human osteoblast and endothelial cell co-culture systems in order to distribute osteoblasts on all parts of the bone scaffold and at the same time provide conditions for the endothelial cells to migrate to form a network of capillary-li…
Tissue engineering: how to build a heart
2015
Decellularization and recellularization of hearts from newly dead donors is the latest fashion in cardiac tissue engineering. The first paper came out in 2008 in Nature Medicine (Ott et al., 2008), and news has been recently published in Nature again in July 2013 (Maher, 2013). Brendan Maher in this paper summarizes and comments on the latest important results on decellularization of a human heart and explains the steps that are necessary to build a heart from a decellularized organ. Two sources may be used to obtain a decellularized heart: human and pig heart. Another issue to resolve is the time of decellularization, since the detergents used may also destroy the architecture of the organ…
Wharton’s Jelly Mesenchymal Stromal Cells Support the Expansion of Cord Blood–derived CD34+Cells Mimicking a Hematopoietic Niche in a Direct Cell–cel…
2018
Wharton’s jelly mesenchymal stromal cells (WJ-MSCs) have been recently exploited as a feeder layer in coculture systems to expand umbilical cord blood–hematopoietic stem/progenitor cells (UCB-HSPCs). Here, we investigated the role of WJ-MSCs in supporting ex vivo UCB-HSPC expansion either when cultured in direct contact (DC) with WJ-MSCs or separated by a transwell system or in the presence of WJ-MSC–conditioned medium. We found, in short-term culture, a greater degree of expansion of UCB-CD34+cells in a DC system (15.7 ± 4.1-fold increase) with respect to the other conditions. Moreover, in DC, we evidenced two different CD34+cell populations (one floating and one adherent to WJ-MSCs) with …
Identification of mechanism(s) leading to hyperdiploidy in progenitor tumor cells derived from MCF7 breast cancer cells
2010
Stem cells are a minor population of mostly resting cells defined by their long life, high clonogenicity, self-replicating potential, plasticity, and drug resistance (Finn, 2008). Cells with these properties have been identified in various normal and cancerous human tissues (Wicha, 2006), as well as in several long-term tumor cell lines (Setoguchi, 2004). We have some preliminary data indicating that cells isolated from MCF7 line divide slowly and form spheres, both features of progenitors tumor cells, when grown in ultralow adherent plates and in absence of serum. Furthermore, these features were associated to two distinct populations characterized by different content in terms of number o…
Endothelial Progenitor Cells A New Real Hope?
2017
Chronic inflammatory diseases, such as cardiovascular diseases (CVDs), diabetes, Alzheimer’s disease (AD) and cancer, have a disproportionate prevalence with advancing age owing to the continuous growth in the aging population. This condition determines several medical, economic and social problems due to the dramatic increase in the number of affected individuals, who are not autonomous. Thus, research efforts are centred around reducing and/or delaying the onset and progression of these diseases by researching new strategies for early prevention and diagnosis. In this context, understanding the mechanisms involved in the tissue, organ protection and repair are imperative for the developme…
Radiative 2D Shocks, Super-Eddington Disks and Jets around Black Holes
2005
It is well known that rotating inviscid accretion flows with adequate injection parameters around black holes could form shock waves close to the black holes, after the flow passes through the outer sonic point and can be virtually stopped by the centrifugal force. Such shock waves in 2D accretion flows are examined by 2D radiation hydrodynamical calculations. We also examine super‐Eddington accretion disks with 15 ṀE around black holes, focusing on a small collimation degree of the jet and a large mass‐outflow rate observed in the X‐ray source SS 433.
In vitro differentiation of murine hematopoietic progenitor cells toward the myeloid lineage occurs in response to Staphylococcus aureus and yeast sp…
2013
We have studied the effect of inactivated microbial stimuli (Candida albicans, Candida glabrata, Saccharomyces boulardii, and Staphylococcus aureus) on the in vitro differentiation of lineage negative (Lin−) hematopoietic progenitor mouse cells. Purified Lin− progenitors were co-cultured for 7 days with the stimuli, and cell differentiation was determined by flow cytometry analysis. All the stimuli assayed caused differentiation toward the myeloid lineage. S. boulardii and particularly C. glabrata were the stimuli that induced in a minor extent differentiation of Lin− cells, as the major population of differentiated cells corresponded to monocytes, whereas C. albicans and S. aureus induced …
Gp130-signaling synergizes with FL and TPO for the long-term expansion of cord blood progenitors
1999
We investigated the effect of a new fusion protein of IL-6 and the soluble IL-6R, H-IL-6, on the long-term ex vivo expansion of hematopoietic progenitors derived from AC133+cord blood cells. H-IL-6, which acts on both IL-6Ralpha-positive and IL-6Ralpha-negative cells, effectively synergized with FL and TPO with or without SCF for the propagation of primitive progenitors. However, IL-6 showed a greater synergistic effect with FL and TPO than H-IL-6 for long-term progenitor propagation. During the first 6 weeks of culture under stroma-free serum-containing conditions, IL-6 induced a 1.96 +/- 0.64-fold higher expansion of nucleated cells, a 2.28 +/- 0.33-fold higher expansion of CD34+ cells an…