Search results for "Mesoderm"
showing 10 items of 51 documents
The transcription factor Interferon Regulatory Factor 4 is required for the generation of protective effector CD8 + T cells
2013
Robust cytotoxic CD8 + T-cell response is important for immunity to intracellular pathogens. Here, we show that the transcription factor IFN Regulatory Factor 4 (IRF4) is crucial for the protective CD8 + T-cell response to the intracellular bacterium Listeria monocytogenes . IRF4-deficient ( Irf4 −/− ) mice could not clear L. monocytogenes infection and generated decreased numbers of L. monocytogenes -specific CD8 + T cells with impaired effector phenotype and function. Transfer of wild-type CD8 + T cells into Irf4 −/− mice improved bacterial clearance, suggesting an intrinsic defect of CD8 + T cells in Irf4 −/− mice. Following transfer into wild-type recipients, Irf4 −/− CD8 + T cells bec…
Induction of identified mesodermal cells by CNS midline progenitors in Drosophila.
1997
ABSTRACT The Drosophila ventral midline cells generate a discrete set of CNS lineages, required for proper patterning of the ventral ectoderm. Here we provide the first evidence that the CNS midline cells also exert inductive effects on the mesoderm. Mesodermal progenitors adjacent to the midline progenitor cells give rise to ventral somatic mucles and a pair of unique cells that come to lie dorsomedially on top of the ventral nerve cord, the so-called DM cells. Cell ablation as well as cell transplantation experiments indicate that formation of the DM cells is induced by midline progenitors in the early embryo. These results are corroborated by genetic analyses. Mutant single minded embryo…
The muscleblind gene participates in the organization of Z-bands and epidermal attachments of Drosophila muscles and is regulated by Dmef2.
1998
We report the embryonic phenotype of muscleblind (mbl), a recently described Drosophila gene involved in terminal differentiation of adult ommatidia. mbl is a nuclear protein expressed late in the embryo in pharyngeal, visceral, and somatic muscles, the ventral nerve cord, and the larval photoreceptor system. All three mbl alleles studied exhibit a lethal phenotype and die as stage 17 embryos or first instar larvae. These larvae are partially paralyzed, show a characteristically contracted abdomen, and lack striation of muscles. Our analysis of the somatic musculature shows that the pattern of muscles is established correctly, and they form morphologically normal synapses. Ultrastructural a…
Single cell cultures of Drosophila neuroectodermal and mesectodermal central nervous system progenitors reveal different degrees of developmental aut…
2009
Abstract Background The Drosophila embryonic central nervous system (CNS) develops from two sets of progenitor cells, neuroblasts and ventral midline progenitors, which behave differently in many respects. Neuroblasts derive from the neurogenic region of the ectoderm and form the lateral parts of the CNS. Ventral midline precursors are formed by two rows of mesectodermal cells and build the CNS midline. There is plenty of evidence that individual identities are conferred to precursor cells by positional information in the ectoderm. It is unclear, however, how far the precursors can maintain their identities and developmental properties in the absence of normal external signals. Results To s…
Stress response in mesoangioblast stem cells
2006
Stem cells are presumed to survive various stresses, since they are recruited to areas of tissue damage and regeneration, where inflammatory cytokines and cytotoxic cells may result in severe cell injury. We explored the ability of mesoangioblasts to respond to different cell stresses such as heat, heavy metals and osmotic stress, by analyzing heat shock protein (HSP)70 synthesis as a stress indicator. We found that the A6 mesoangioblast stem cells constitutively synthesize HSP70 in a heat shock transcription factor (HSF)-independent way. However, A6 respond to heat shock and cadmium treatment by synthesizing HSP70 over the constitutive expression and this synthesis is HSF1 dependent. The e…
New emerging potentials for human Wharton's jelly mesenchymal stem cells: immunological features and hepatocyte-like differentiative capacity.
2010
In recent years, human mesenchymal stem cells (MSC) have been extensively studied. Their key characteristics of long-term self-renewal and a capacity to differentiate into diverse mature tissues favour their use in regenerative medicine applications. Stem cells can be found in embryonic and extra-embryonic tissues as well as in adult organs. Several reports indicate that cells of Wharton's jelly (WJ), the main component of umbilical cord extracellular matrix, are multipotent stem cells, expressing markers of bone marrow mesenchymal stem cells (BM-MSC), and giving rise to different cellular types of both connective and nervous tissues. Wharton's jelly mesenchymal stem cells (WJ-MSC) express …
In vivo fate mapping with SCL regulatory elements identifies progenitors for primitive and definitive hematopoiesis in mice.
2009
10 páginas, 6 figuras.-- et al.
La distribuzione dell'attività proteasica nella blastula e nella giovane gastrula diDiscoglossus pictus
1956
Summary Protease activity has been measured in the animal and vegetal half of the blastula and in the dorsal and ventral regions of the early gastrula of Discoglossus pictus. A higher protease activity was found in the dorsal region of the early gastrula, where presumptive chordamesoderm and presumptive neuroectoderm are localized.
EGFR signalling is required for Paracentrotus lividus endomesoderm specification
2008
The EGFR pathway is critical for cell fate specification throughout the development of several organisms. Here we identified in sea urchin an EGFR-related antigen maternally expressed and showing a dynamic pattern of localization during development. To investigate the role played by the EGFR in Paracentrotus lividus development we blocked its activity by using the EGFR kinase inhibitor AG1478. This treatment produces decrease of EGFR phosphorylation, and embryos with various defects especially in the endomesoderm territory until to obtain an animalized phenotype. These effects are rescued by the addition of TGF-alpha, an EGFR ligand. The role played by EGFR-like along the animal/vegetal axi…
An acid extract from dissociation medium of sea urchin embryos, induces mesenchyme differentiation
1992
Abstract When material extracted by 1 M acetic acid from the dissociation medium of sea urchin embryos is added at low concentrations to isolated primary mesenchyme cells, it induces skeletogenesis. The same material added to dissociated blastula cells, or to embryos at the blastula stage, stimulates skeleton formation and pigment cell differentiation. On dissociated cells, it also increases cell reaggregation, thymidine incorporation and survival. On embryos, it induces exogastrulation and appearence of extraembryonic pigment cells. The activity of the extract is resistant to raised temperatures and partially to tryptic digestion but is abolished by trypsin treatment followed by heating. T…