Search results for "Bone Marrow Cells"
showing 10 items of 120 documents
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 …
The efficient bovine insulin presentation capacity of bone marrow-derived macrophages activated by granulocyte-macrophage colony-stimulating factor c…
1993
Bone marrow-derived macrophages (BMM phi) were shown before to function as antigen-presenting cells. We show here, that the antigen presentation capacity of BMM phi depends on the nature of the antigen and is differently regulated by the lymphokines interferon-gamma (IFN-gamma) and granulocyte/macrophage-colony-stimulating factor (GM-CSF). When bovine insulin (BI) was employed as antigen, only BMM phi treated with GM-CSF (GM-CSF-M phi) were efficient presenters, but when presentation of the antigens ovalbumin and conalbumin was tested, IFN-gamma-pulsed BMM phi (IFN-gamma-M phi) proved superior to GM-CSF-M phi. The lack of efficient BI presentation function of IFN-gamma-M phi was only obviou…
Dendritic cells trigger tumor cell death by a nitric oxide-dependent mechanism.
2007
Abstract Dendritic cells (DCs) are well known for their capacity to induce adaptive antitumor immune response through Ag presentation and tumor-specific T cell activation. Recent findings reveal that besides this role, DCs may display additional antitumor effects. In this study, we provide evidence that LPS- or IFN-γ-activated rat bone marrow-derived dendritic cells (BMDCs) display killing properties against tumor cells. These cytotoxic BMDCs exhibit a mature DC phenotype, produce high amounts of IL-12, IL-6, and TNF-α, and retain their phagocytic properties. BMDC-mediated tumor cell killing requires cell-cell contact and depends on NO production, but not on perforin/granzyme or on death re…
P-selectin glycoprotein ligand-1 as a potential target for humoral immunotherapy of multiple myeloma.
2008
Monoclonal antibodies (mAbs), successfully adopted in the treatment of several haematological malignancies, have proved almost ineffective in multiple myeloma (MM), because of the lack of an appropriate antigen for targeting and killing MM cells. Here, we demonstrate that PSGL1, the major ligand of P-Selectin, a marker of plasmacytic differentiation expressed at high levels on normal and neoplastic plasma cells, may represent a novel target for mAb-mediated MM immunotherapy. The primary effectors of mAb-induced cell-death, complement-mediated lysis (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC), were investigated using U266B1 and LP1 cell-lines as models. Along with immunolo…
Defective apoptosis as potential mechanism in the tumorogenesis of myelolipoma
1999
Apoptosis is considered an important mechanism of selective deletion that occurs during hematopoiesis. Myelolipoma is a rare benign tumor composed of adipose tissue and hematopoietic cells. The pathogenesis of this benign tumor is still unclear. Analysing the structural levels and apoptosis of normal human bone marrow (NHBM) and human myelolipoma (HM), the apoptotic events resulted abundantly present in NHBM compared to HM, which showed a small number of apoptotic cells. By contrast, Fas expression was strongly present both in NHBM and HM. These findings suggest that an altered function of Fas in myelolipoma is not able to trigger the apoptotic machinery. In conclusion, we hypothesize that …
Can bone marrow-derived multipotent adult progenitor cells regenerate infarcted myocardium?
2006
Objectives: To assess the functional effects of multipotent adult progenitor cells (MAPCs) transplanted in a rat model of chronic myocardial infarction. Methods: Forty-four rats underwent coronary ligation and, 14 days later, were randomly allocated to receive in-scar injections (5×106 cells/150 μL) of green fluorescent protein (eGFP)-transduced allogeneic MAPCs ( n =25) or culture medium (controls, n =19). Nine of the MAPC-treated hearts were employed for functional studies while the remaining 16 received cells co-labeled with Resovist™ and were only used for serial histological assessments. Left ventricular (LV) function was assessed echocardiographically before transplantation and 1 mont…
Contact Sensitizers Specifically Increase MHC Class II Expression on Murine Immature Dendritic Cells
2000
Contact sensitivity is a T-cell-mediated immune disease that can occur when low-molecular-weight chemicals penetrate the skin. In vivo topical application of chemical sensitizers results in morphological modification of Langerhans cells (LC). Moreover, within 18 h, LC increase their major histocompatibility complex (MHC) class II antigens expression and migrate to lymph nodes where they present the sensitizer to T lymphocytes. We wanted to determine if such an effect could also be observed in vitro. However, because of the high genetic diversity encountered in humans, assays were performed with dendritic cells (DC) obtained from a Balb/c mouse strain. The capacity of a strong sensitizer, DN…
Epigenetic and in vivo comparison of diverse MSC sources reveals an endochondral signature for human hematopoietic niche formation
2015
In the last decade there has been a rapid expansion in clinical trials using mesenchymal stromal cells (MSCs) from a variety of tissues. However, despite similarities in morphology, immunophenotype, and differentiation behavior in vitro, MSCs sourced from distinct tissues do not necessarily have equivalent biological properties. We performed a genome-wide methylation, transcription, and in vivo evaluation of MSCs from human bone marrow (BM), white adipose tissue, umbilical cord, and skin cultured in humanized media. Surprisingly, only BM-derived MSCs spontaneously formed a BM cavity through a vascularized cartilage intermediate in vivo that was progressively replaced by hematopoietic tissue…
PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide-Based Polymersomes.
2017
In this work, the first vaccine is reported based on a PeptoSome, which contains a model antigen (SIINFEKL) and adjuvant (CpG). PeptoSomes are polypept(o)ide-based polymersomes built of a block-copolymer with polysarcosine (PSar) as the hydrophilic block (X n = 111) and poly(benzyl-glutamic acid) (PGlu(OBn)) as the hydrophobic one (X n = 46). The polypept(o)ide is obtained with low dispersity index of 1.32 by controlled ring-opening polymerization. Vesicle formation by dual centrifugation technique allows for loading of vesicles up to 40 mol%. PeptoSomes are characterized by multiangle dynamic light scattering, static light scattering, and cryogenic transmission electron microscopy (cryoTEM…
Macrophages Escape Inhibition of Major Histocompatibility Complex Class I-Dependent Antigen Presentation by Cytomegalovirus
2000
ABSTRACTThe mouse cytomegalovirus (MCMV)m152- andm06-encoded glycoproteins gp40 and gp48, respectively, independently downregulate major histocompatibility complex (MHC) class I surface expression during the course of productive MCMV infection in fibroblasts. As a result, presentation of an immediate-early protein pp89-derived nonapeptide toH-2Ld-restricted CD8+cytotoxic T cells is completely prevented in fibroblasts. Here we demonstrate that MCMV-infected primary bone marrow macrophages and the macrophage cell line J774 constitutively present pp89 peptides during permissive MCMV infection to cytotoxic T lymphocytes (CTL). In contrast to fibroblasts, expression of them152andm06genes in macr…