Search results for "cellular"
showing 10 items of 6449 documents
Alkaline phosphatase dual-binding sites for collagen dictate cell migration and microvessel assembly in vitro
2020
Interactions between cell types, growth factors, and extracellular matrix components involved in angiogenesis are crucial for new vessel formation leading to tissue regeneration. This study investigated whether cocultures of fibroblasts and endothelial cells (ECs; from macro- or microvasculature) play a role in the formation of microvessel-like structures by ECs, as well as modulate fibroblast differentiation and growth factors production (vascular endothelial cell growth factor, basic fibroblast growth factor, active transforming growth factor-beta 1, and interleukin-8), which are important for vessel sprouting and maturation. Data obtained revealed that in vitro coculture systems of fibro…
Trans-presentation of IL-6 by dendritic cells is required for the priming of pathogenic TH17 cells
2016
The cellular sources of interleukin 6 (IL-6) that are relevant for differentiation of the TH17 subset of helper T cells remain unclear. Here we used a novel strategy for the conditional deletion of distinct IL-6-producing cell types to show that dendritic cells (DCs) positive for the signaling regulator Sirpα were essential for the generation of pathogenic TH17 cells. Using their IL-6 receptor α-chain (IL-6Rα), Sirpα+ DCs trans-presented IL-6 to T cells during the process of cognate interaction. While ambient IL-6 was sufficient to suppress the induction of expression of the transcription factor Foxp3 in T cells, trans-presentation of IL-6 by DC-bound IL-6Rα (called 'IL-6 cluster signaling'…
Autophagy in the pathogenesis of ankylosing spondylitis
2016
The pathogenesis of ankylosing spondylitis (AS) is not well understood, and treatment options have met with limited success. Autophagy is a highly conserved mechanism of controlled digestion of damaged organelles within a cell. It helps in the maintenance of cellular homeostasis. The process of autophagy requires the formation of an isolation membrane. They form double-membraned vesicles called “autophagosomes” that engulf a portion of the cytoplasm. Beyond the role in maintenance of cellular homeostasis, autophagy has been demonstrated as one of the most remarkable tools employed by the host cellular defense against bacteria invasion. Autophagy also affects the immune system and thus is im…
The HDAC6 Inhibitor tubacin induces release of CD133+ extracellular vesicles from cancer cells
2017
Tumor-derived extracellular vesicles (EVs) are emerging as an important mode of intercellular communication, capable of transferring biologically active molecules that facilitate the malignant growth and metastatic process. CD133 (Prominin-1), a stem cell marker implicated in tumor initiation, differentiation and resistance to anti-cancer therapy, is reportedly associated with EVs in various types of cancer. However, little is known about the factors that regulate the release of these CD133+ EVs. Here, we report that the HDAC6 inhibitor tubacin promoted the extracellular release of CD133+ EVs from human FEMX-I metastatic melanoma and Caco-2 colorectal carcinoma cells, with a concomitant dow…
Long Term Culture of the A549 Cancer Cell Line Promotes Multilamellar Body Formation and Differentiation towards an Alveolar Type II Pneumocyte Pheno…
2016
Pulmonary research requires models that represent the physiology of alveolar epithelium but concerns with reproducibility, consistency and the technical and ethical challenges of using primary or stem cells has resulted in widespread use of continuous cancer or other immortalized cell lines. The A549 'alveolar' cell line has been available for over four decades but there is an inconsistent view as to its suitability as an appropriate model for primary alveolar type II (ATII) cells. Since most work with A549 cells involves short term culture of proliferating cells, we postulated that culture conditions that reduced proliferation of the cancer cells would promote a more differentiated ATII ce…
MOBP levels are regulated by Fyn kinase and affect the morphological differentiation of oligodendrocytes.
2015
Oligodendrocytes are the myelinating glial cells of the central nervous system (CNS). Myelin is formed by extensive wrapping of oligodendroglial processes around axonal segments which ultimately allows a rapid saltatory conduction of action potentials within the CNS and sustains neuronal health. The non-receptor tyrosine kinase Fyn is an important signaling molecule in oligodendrocytes. It controls the morphological differentiation of oligodendrocytes and is an integrator of axon-glial signaling cascades leading to localized synthesis of Myelin Basic Protein (MBP) which is essential for myelin formation. The abundant Myelin-Associated Oligodendrocytic Basic Protein (MOBP) resembles MBP in s…
Epigenetic Regulation of Cardiac Differentiation of Embryonic Stem Cells and Tissues.
2016
International audience; Specific gene transcription is a key biological process that underlies cell fate decision during embryonic development. The biological process is mediated by transcription factors which bind genomic regulatory regions including enhancers and promoters of cardiac constitutive genes. DNA is wrapped around histones that are subjected to chemical modifications. Modifications of histones further lead to repressed, activated or poised gene transcription, thus bringing another level of fine tuning regulation of gene transcription. Embryonic Stem cells (ES cells) recapitulate within embryoid bodies (i.e., cell aggregates) or in 2D culture the early steps of cardiac developme…
Bifunctional Hydrogels Containing the Laminin Motif IKVAV Promote Neurogenesis
2017
Summary Engineering of biomaterials with specific biological properties has gained momentum as a means to control stem cell behavior. Here, we address the effect of bifunctionalized hydrogels comprising polylysine (PL) and a 19-mer peptide containing the laminin motif IKVAV (IKVAV) on embryonic and adult neuronal progenitor cells under different stiffness regimes. Neuronal differentiation of embryonic and adult neural progenitors was accelerated by adjusting the gel stiffness to 2 kPa and 20 kPa, respectively. While gels containing IKVAV or PL alone failed to support long-term cell adhesion, in bifunctional gels, IKVAV synergized with PL to promote differentiation and formation of focal adh…
The activation of Wnt signaling by a STAT6-dependent macrophage phenotype promotes mucosal repair in murine IBD
2016
The complete repair of the mucosa constitutes a key goal in inflammatory bowel disease (IBD) treatment. The Wnt signaling pathway mediates mucosal repair and M2 macrophages that coordinate efficient healing have been related to Wnt ligand expression. Signal transducer and activator of transcription 6 (STAT6) mediates M2 polarization in vitro and we hypothesize that a STAT6-dependent macrophage phenotype mediates mucosal repair in acute murine colitis by activating the Wnt signaling pathway. Our results reveal an impaired mucosal expression of M2 macrophage-associated genes and delayed wound healing in STAT6(-/-) mice treated with 2,4,6-trinitrobenzenesulfonic acid (TNBS). These mice also ex…
Candida albicansis able to use M cells as a portal of entry across the intestinal barrierin vitro
2015
Candida albicans is the most frequent yeast responsible for systemic infections in humans. These infections mainly originate from the gastrointestinal tract where C. albicans can invade the gut epithelial barrier to gain access to the bloodstream. Along the gut, pathogens can use Microfold (M) cells as a portal of entry to cross the epithelial barrier. M cells are specialized cells mainly located in the follicule-associated epithelium of Peyer patches. In this study, we used scanning electron and fluorescence microscopy, adhesion and invasion assays and fungal mutants to investigate the interactions of C. albicans with M cells obtained in an established in vitro model whereby enterocyte-lik…