Search results for "Stromal Cells."

Adult Stem Cell-Derived Extracellular Vesicles in Cancer Treatment: Opportunities and Challenges

2020

Adult stem cells (SCs) participate in tissue repair and homeostasis regulation. The relative ease of SC handling and their therapeutic effect has made of these cell popular candidates for cellular therapy. However, several problems interfere with their clinical application in cancer treatment, like safety issues, unpredictable pro-tumour effects, and tissue entrapment. Therefore cell-free therapies that exhibit SC properties are being investigated. It is now well known that adult SCs exhibit their therapeutic effect via paracrine mechanisms. In addition to secretory proteins, SCs also release extracellular vesicles (EV) that deliver their contents to the target cells. Cancer treatment is on…

Umbilical cord versus bone marrow-derived mesenchymal stromal cells.

2012

incetheplacentaisapostnatal tissue and discarded asmedical waste, harvesting stem cells from this organrepresents a noninvasive and ethically conductive proce-dure. Perinatal stem cells isolated from amnion, chorion,umbilical cord, and cord blood are increasingly viewedas reliable sources of mesenchymal stromal cells (MSCs)alternative to bone marrow-derived ones (BM-MSCs),which are currently the most commonly used in clinicalapplications [1–5].Perinatal stem cells are a bridge between embryonic stemcells (ESCs) and adult stem cells (such as BM-MSCs). Theyshare many characteristics of both cells [1,6]. Considering thestructural complexity of the term ‘‘placenta,’’ we have fo-cused our attent…

Evidence for a common progenitor of epithelial and mesenchymal components of the liver

2013

Tissues of the adult organism maintain the homeostasis and respond to injury by means of progenitor/stem cell compartments capable to give rise to appropriate progeny. In organs composed by histotypes of different embryological origins (e.g. The liver), the tissue turnover may in theory involve different stem/precursor cells able to respond coordinately to physiological or pathological stimuli. In the liver, a progenitor cell compartment, giving rise to hepatocytes and cholangiocytes, can be activated by chronic injury inhibiting hepatocyte proliferation. The precursor compartment guaranteeing turnover of hepatic stellate cells (HSCs) (perisinusoidal cells implicated with the origin of the …

A combined approach for gene discovery identifies insulin-like growth factor-binding protein-related protein 1 as a new gene implicated in human endo…

2003

In the past, human endometrial receptivity has been investigated by chasing specific molecules throughout the menstrual cycle. Now the genomic approach allows us to investigate the hierarchical contribution of a high number of genes to a specific function. In this study, we analyzed differentially the gene expression pattern of 375 human cytokines, chemokines, and related factors, plus that of their receptors, in endometrial receptivity. To do this, we used a combined approach of human endometrium and cell lines. We have compared the gene expression pattern in receptive vs. prereceptive human endometria and contrasted the results with gene expression in the highly adhesive cell line (to JAR…

Induced Pluripotent Mesenchymal Stromal Cell Clones Retain Donor-derived Differences in DNA Methylation Profiles

2012

Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) is an epigenetic phenomenon. It has been suggested that iPSC retain some tissue-specific memory whereas little is known about interindividual epigenetic variation. We have reprogrammed mesenchymal stromal cells from human bone marrow (iP-MSC) and compared their DNA methylation profiles with initial MSC and embryonic stem cells (ESCs) using high-density DNA methylation arrays covering more than 450,000 CpG sites. Overall, DNA methylation patterns of iP-MSC and ESC were similar whereas some CpG sites revealed highly significant differences, which were not related to parental MSC. Furthermore, hypermethylation in iP-MSC…

Interferon-α as an Antagonist to Proinflammatory and Hematopoietic Cytokines

1994

Regulation of hematopoietic growth factor production by genetically modified human bone marrow stromal cells expressing interleukin-1beta antisense R…

2001

Interleukin-1 (IL-1) plays a major role in the regulation of bone marrow stromal cell function and hematopoiesis. It is known to induce secretion of the hematopoietic growth factors granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage CSF (GM-CSF), IL-6, and IL-8 as well as IL-1 itself in stromal cells. We investigated the role of IL-1beta-mediated growth factor production in the human stromal cell line L88/5. Using liposome-mediated DNA transfer, two stromal cell transfectants that constitutively express IL-1beta antisense (AS) RNA were generated. Expression of IL-1beta AS RNA and IL-1beta RNA was determined by RT-PCR. The stromal cell transfectants were strongly impaired …

Wnt3a Neutralization Enhances T-cell Responses through Indirect Mechanisms and Restrains Tumor Growth

2018

Abstract The Wnt/β-catenin pathway regulates T-cell functions, including the repression of effector functions to the advantage of memory development via Tcf1. In a companion study, we demonstrate that, in human cancers, Wnt3a/β-catenin signaling maintains tumor-infiltrating T cells in a partially exhausted status. Here, we have investigated the effects of Wnt3a neutralization in vivo in a mouse tumor model. Abundant Wnt3a was released, mostly by stromal cells, in the tumor microenvironment. We tested whether Wnt3a neutralization in vivo could rescue the effector capacity of tumor-infiltrating T cells, by administering an antibody to Wnt3a to tumor-bearing mice. This therapy restrained tumor…

Podoplanin discriminates distinct stromal cell populations and a novel progenitor subset in the liver

2015

Podoplanin/gp38+ stromal cells present in lymphoid organs play a central role in the formation and reorganization of the extracellular matrix and in the functional regulation of immune responses. Gp38+ cells are present during embryogenesis and in human livers of primary biliary cirrhosis. Since little is known about their function, we studied gp38+ cells during chronic liver inflammation in models of biliary and parenchymal liver fibrosis and steatohepatitis. Gp38+ cells were analyzed using flow cytometry and confocal microscopy, and the expression of their steady state and inflammation-associated genes was evaluated from healthy and inflamed livers. Gp38+ cells significantly expanded in …

Exosome-mediated crosstalk between chronic myelogenous leukemia cells and human bone marrow stromal cells triggers an Interleukin 8-dependent surviva…

2014

Chronic myelogenous leukemia (CML) is a myeloproliferative disorder characterized by the Bcr-Abl oncoprotein with constitutive tyrosine kinase activity. Exosomes are nanovesicles released by cancer cells that are involved in cell-to-cell communication thus potentially affecting cancer progression. It is well known that bone marrow stromal microenvironment contributes to disease progression through the establishment of a bi-directional crosstalk with cancer cells. Our hypothesis is that exosomes could have a functional role in this crosstalk. Interleukin-8 (IL 8) is a proinflammatory chemokine that activates multiple signalling pathways downstream of two receptors (CXCR1 and CXCR2). We demon…