Search results for " stroma"
showing 10 items of 172 documents
Morphogenetically-Active Barrier Membrane for Guided Bone Regeneration, Based on Amorphous Polyphosphate
2017
We describe a novel regeneratively-active barrier membrane which consists of a durable electrospun poly(ε-caprolactone) (PCL) net covered with a morphogenetically-active biohybrid material composed of collagen and inorganic polyphosphate (polyP). The patch-like fibrous collagen structures are decorated with small amorphous polyP nanoparticles (50 nm) formed by precipitation of this energy-rich and enzyme-degradable (alkaline phosphatase) polymer in the presence of calcium ions. The fabricated PCL-polyP/collagen hybrid mats are characterized by advantageous biomechanical properties, such as enhanced flexibility and stretchability with almost unaltered tensile strength of the PCL net. The pol…
Structural, ultrastructural, and morphometric study of the zebrafish ocular surface: a model for human corneal diseases?
2018
Purpose: A morphological and morphometric study of the adult zebrafish ocular surface was performed to provide a comprehensive description of its parts and to evaluate its similarity to the human. Materials and Methods: The eyes of adult zebrafish were processed for light, transmission and scanning electron microscopy, and for immunohistochemical stain of corneal nerves; a morphometric analysis was also performed on several morphological parameters. Results: The corneal epithelium was formed by five layers of cells. No Bowman’s layer could be demonstrated. The stroma consisted of lamellae of different thickness with few keratocytes. The Descemet’s membrane was absent as the flat and polygon…
Persistent immune stimulation exacerbates genetically driven myeloproliferative disorders via stromal remodeling
2017
Abstract Systemic immune stimulation has been associated with increased risk of myeloid malignancies, but the pathogenic link is unknown. We demonstrate in animal models that experimental systemic immune activation alters the bone marrow stromal microenvironment, disarranging extracellular matrix (ECM) microarchitecture, with downregulation of secreted protein acidic and rich in cysteine (SPARC) and collagen-I and induction of complement activation. These changes were accompanied by a decrease in Treg frequency and by an increase in activated effector T cells. Under these conditions, hematopoietic precursors harboring nucleophosmin-1 (NPM1) mutation generated myeloid cells unfit for normal …
Interleukin-31 and thymic stromal lymphopoietin expression in plasma and lymph node from Hodgkin lymphoma patients
2017
Hodgkin Lymphoma (HL) is a tumor of B-cell origin characterized by Hodgkin and Reed-Stenberg (H/RS) cells embedded in an inflammatory tissue where numerous cytokines/chemokines contribute to shape the microenvironment, leading to the typical clinical symptoms. We investigated: i) the expression of Interleukin-IL-31 (IL-31) and Thymic Stromal Lymphopoietin (TSLP), two Th2-related cytokines with tumor-promoting and pruritogenic functions, and of the respective receptors in HL invaded lymph nodes by flow cytometry, and ii) the potential association of IL-31/TSLP plasma concentrations with clinical characteristics by ELISA. H/RS cells and the major immune cell types infiltrating HL lymph nodes …
Proton Leakage Is Sensed by IM30 and Activates IM30-Triggered Membrane Fusion
2020
The inner membrane-associated protein of 30 kDa (IM30) is crucial for the development and maintenance of the thylakoid membrane system in chloroplasts and cyanobacteria. While its exact physiological function still is under debate, it has recently been suggested that IM30 has (at least) a dual function, and the protein is involved in stabilization of the thylakoid membrane as well as in Mg2+-dependent membrane fusion. IM30 binds to negatively charged membrane lipids, preferentially at stressed membrane regions where protons potentially leak out from the thylakoid lumen into the chloroplast stroma or the cyanobacterial cytoplasm, respectively. Here we show in vitro that IM30 membrane binding…
Wharton's Jelly Mesenchymal Stromal Cells as a Feeder Layer for the Ex Vivo Expansion of Hematopoietic Stem and Progenitor Cells: a Review
2016
In recent years, umbilical cord blood (UCB) has been widely used as an alternative source to bone marrow (BM) for transplantation of hematopoietic stem and progenitor cells (HSPCs) in a variety of hematological and non-hematological disorders. Nevertheless, the insufficient number of UCB-HSPCs for graft represents a major challenge. HSPCs ex vivo expansion prior to transplantation is a valid strategy to overcome this limit. Several attempts to optimize the expansion conditions have been reported, including the use of mesenchymal stromal cells (MSCs) as feeder layer. Wharton's Jelly (WJ), the main component of umbilical cord (UC) matrix, is especially rich in MSCs, which are considered ideal…
Are Long Noncoding RNAs New Potential Biomarkers in Gastrointestinal Stromal Tumors (GISTs)? The Role of H19 and MALAT1
2019
Long noncoding RNAs (lncRNAs) are emerging as key regulators of genetic and epigenetic networks, and their deregulation may underlie complex diseases, such as carcinogenesis. Several studies described lncRNA alterations in patients with solid tumors. In particular, HOTAIR upregulation has been associated with tumor aggressiveness, metastasis, and poor survival in gastrointestinal stromal tumor (GIST) patients. We analyzed expression levels of other lncRNAs, H19 and MALAT1, in FFPE tissue specimens from 40 surgically resected and metastatic GIST patients, using real-time PCR analysis. H19 and MALAT1 were both upregulated in 50% of GIST patients. MALAT1 lncRNA expression levels seem to be cor…
Galectin-3 is a marker of favorable prognosis and a biologically relevant molecule in neuroblastic tumors
2014
Childhood neuroblastic tumors are characterized by heterogeneous clinical courses, ranging from benign ganglioneuroma (GN) to highly lethal neuroblastoma (NB). Although a refined prognostic evaluation and risk stratification of each tumor patient is becoming increasingly essential to personalize treatment options, currently only few biomolecular markers (essentially MYCN amplification, chromosome 11q status and DNA ploidy) are validated for this purpose in neuroblastic tumors. Here we report that Galectin-3 (Gal-3), a β-galactoside-binding lectin involved in multiple biological functions that has already acquired diagnostic relevance in specific clinical settings, is variably expressed in m…
Analysis of the immune microenvironment in resected non-small cell lung cancer: the prognostic value of different T lymphocyte markers
2016
[EN] The prognosis of non-small cell lung cancer (NSCLC) remains poor and heterogeneous and new biomarkers are needed. As the immune system plays a pivotal role in cancer, the study of immune-related markers may provide valuable prognostic information of NSCLC. In 122 formalin-fixed, paraffin-embedded tumor tissue samples from early-stage NSCLC, tumor and tumor-near stromal areas were microdissected and gene expression levels of conventional and regulatory T cell markers were assessed by quantitative polymerase chain reaction. Also, the presence of infiltrating CD4+, CD8+, and FOXP3+ cells in tumor samples was assessed by immunohistochemistry. The relative proportion of conventional and reg…
Microenvironment in neuroblastoma: isolation and characterization of tumor-derived mesenchymal stromal cells
2018
Background It has been proposed that mesenchymal stromal cells (MSCs) promote tumor progression by interacting with tumor cells and other stroma cells in the complex network of the tumor microenvironment. We characterized MSCs isolated and expanded from tumor tissues of pediatric patients diagnosed with neuroblastomas (NB-MSCs) to define interactions with the tumor microenvironment. Methods Specimens were obtained from 7 pediatric patients diagnosed with neuroblastoma (NB). Morphology, immunophenotype, differentiation capacity, proliferative growth, expression of stemness and neural differentiation markers were evaluated. Moreover, the ability of cells to modulate the immune response, i.e. …