Search results for " STEM CELLS"

Polypeptides controlling hematopoietic cell development and activation. I. In vitro results.

1989

Recombinant DNA technology has been central in answering some of the most relevant questions in the research of regulation of the functional status of hematopoietic progenitor cells and their progeny. This leading article will focus on recent results that have emerged from studies utilizing recombinant molecules that control hematopoietic blood cell development and activation. The following features will be detailed: The molecular and biological characteristics and biochemistry of hematopoietic growth factors, synergizing factors and releasing factors, their role in the regulation of hematopoiesis and activation of normal and leukemic cells, their cellular sources, and regulation of product…

Polypeptides controlling hematopoietic blood cell development and activation

1989

Colony-stimulating factors (CSFs) have entered the clinical arena. Several investigators have explored, in first clinical phase I studies, different routes of administration to define the optimum biological dose, maximum tolerated dose, toxicity, and pharmacokinetics of these reagents. It has been demonstrated that recombinant human (rh) granulocyte-macrophage CSF (GM-CSF) and granulocyte CSF (G-CSF) can be safely administered over a broad dose range to increase number of circulating granulocytes in man. More recently, GM-CSF and G-CSF have been involved in phase Ib/II studies to assess the granulopoietic responses of patients with granulocytopenia due to various underlying disease states i…

Imaging of VSOP labeled stem cells in agarose phantoms with susceptibility weighted and T2* weighted MR Imaging at 3T: determination of the detection…

2013

Objectives This study aimed to evaluate the detectability of stem cells labeled with very small iron oxide particles (VSOP) at 3T with susceptibility weighted (SWI) and T2* weighted imaging as a methodological basis for subsequent examinations in a large animal stroke model (sheep). Materials and Methods We examined ovine mesenchymal stem cells labeled with VSOP in agarose layer phantoms. The experiments were performed in 2 different groups, with quantities of 0–100,000 labeled cells per layer. 15 different SWI- and T2*-weighted sequences and 3 RF coils were used. All measurements were carried out on a clinical 3T MRI. Images of Group A were analyzed by four radiologists blinded for the num…

Cytotoxicity of natural products and derivatives toward MCF-7 cell monolayers and cancer stem-like mammospheres

2015

Abstract Although cancer stem-like cells (CSCs) are rare, they can enter a non-proliferative or dormant state and resist therapy. Furthermore, quiescent CSCs are responsible for metastases that can appear after curative surgical treatment of a primary tumor. Because of drug resistance of CSCs, the development of novel therapies is urgently required that specifically target CSCs. Purpose The aim of the present study was to investigate the potential of a panel of natural products and derivatives to inhibit CSC-enriched mammospheres of MCF-7 breast cancer cells. Methods CD44high/CD24low cells were identified by flow cytometry and maintained as mammospheres. As a control, we used two clinically…

Cancer-Initiating Cells from Colorectal Cancer Patients Escape from T Cell-Mediated Immunosurveillance In Vitro through Membrane-Bound IL-4

2014

Abstract Cancer-initiating cells (CICs) that are responsible for tumor initiation, propagation, and resistance to standard therapies have been isolated from human solid tumors, including colorectal cancer (CRC). The aim of this study was to obtain an immunological profile of CRC-derived CICs and to identify CIC-associated target molecules for T cell immunotherapy. We have isolated cells with CIC properties along with their putative non-CIC autologous counterparts from human primary CRC tissues. These CICs have been shown to display “tumor-initiating/stemness” properties, including the expression of CIC-associated markers (e.g., CD44, CD24, ALDH-1, EpCAM, Lgr5), multipotency, and tumorigenic…

Paracrine effect of membrane vesicles released by mouse mesoangioblast stem cells

2016

Introduction: Mouse mesoangioblasts are vessel-associated multipotent progenitor stem cells, which are able to differentiate into different mesodermal cell types. In our previous paper, we have demonstrated that mesoangioblasts are able to shed in the extracellular environment membrane vesicles (EVs), which contain both structural proteins and biological factors such as FGF2 and the two gelatinases MMP2/9. We investigated whether these EV interact in a paracrine way with other cell types different from mesoangioblasts, and eventually the effects of this interaction. Methods: Mesoangioblast EVs were collected from conditioned media by ultracentrifugation. Total mRNAs from mesoangioblasts and…

CD40 activity on mesenchymal cells negatively regulates OX40L to maintain bone marrow immune homeostasis under stress conditions

2021

BackgroundWithin the bone marrow (BM), mature T cells are maintained under homeostatic conditions to facilitate proper hematopoietic development. This homeostasis depends upon a peculiar elevated frequency of regulatory T cells (Tregs) and immune regulatory activities from BM-mesenchymal stem cells (BM-MSCs). In response to BM transplantation (BMT), the conditioning regimen exposes the BM to a dramatic induction of inflammatory cytokines and causes an unbalanced T-effector (Teff) and Treg ratio. This imbalance negatively impacts hematopoiesis, particularly in regard to B-cell lymphopoiesis that requires an intact cross-talk between BM-MSCs and Tregs. The mechanisms underlying the ability of…

Extended characterization of human umbilical cord matrix mesenchymal stem cells: expression of novel markers, immunoregulatory molecules, and differe…

2009

Isolation and characterization of human extraembryonal mesoderm mesenchymal stem cells from umbilical cord

2007

Audzēja ekstracelulāro vezikulu loma mezenhimālo cilmes šūnu sekrēcijas profila izmaiņās

2017

Ekstarcelulārās vezikulas ir mazi pūslīši, kas tiek atbrīvoti no šūnām un izlaisti starpšūnu vidē. EV satur saimniekšūnu ģenētisko materiālu vai to daļas un caur tām viena šūna var nodot informācijas signālu otrai šūnai, tādā veidā ietekmējot to darbību. Arī vēža šūnas var atbrīvot šādas vezikulas un iedarboties uz blakusesošajām gan saimniekorganisma šūnām, gan pašām vēža šūnām. Caur šādu komunikāciju vēža šūnas var pārnest savu izmainīto ģenētisko materiālu uz normālajām šūnām un pārregulēt to darbības mehānismus, kas darbotos audzēja šūnu labā. Darba mērķis bija noskaidrot vai audzēja EV var izraisīt IL-8 un VEGF sekrēcijas izmaiņas ādas mezenhimālajās cilmes šūnās. Lai to noskaidrotu, I…