Search results for "Lipopolysaccharide Receptors"
showing 10 items of 32 documents
Monocytes derived from humanized neonatal NOD/SCID/IL2Rγ(null) mice are phenotypically immature and exhibit functional impairments.
2012
Trials of immune-modulating drugs in septic patients have mostly failed to demonstrate clinical efficacy. Thus, we sought to generate a surrogate model of myelomonocytic lineage differentiation that would potentially allow sepsis induction and preclinical testing of anti-inflammatory drugs. Comparing transplantation of cord blood-derived stem cells in neonatal NOD/SCID/IL2Rγ(null) (neonatal huNSG) mice with transplantation of adult peripheral mobilized stem cells into adult NSG (adult huNSG) recipients, we demonstrate that myelomonocytic lineage differentiation in neonatal huNSG mice is retarded and monocytes are phenotypically immature with respect to HLA-DR expression and the emergence of…
The anti-CD14 antibody IC14 suppresses ex vivo endotoxin stimulated tumor necrosis factor-alpha in patients with chronic heart failure
2006
Background: Activation of the endotoxin (LPS) receptor, CD14, leads to tumor necrosis factor-alpha (TNF) production. Plasma LPS activity is elevated in patients with severe chronic heart failure (CHF). An anti-CD14 antibody, IC14, blocks TNF production in healthy volunteers. It is not known whether IC14 prevents TNF production in CHF patients. Methods and results: Blood from 20 CHF patients (age 64±2.1 years, NYHA class 2.2±0.1, LVEF 27±3%, mean±SEM) was pre-incubated with 0.5, 1.0, 5.0, 10 and 50 μg/mL IC14 for 1 h followed by incubation with 1 or 10 ng/mL LPS for 6 h. Fourteen subjects served as controls (58±2.4 years). LPS-stimulated TNF release was 76% and 60% greater at 1 and 10 ng/mL …
CD14 C (-260)T polymorphism, atherosclerosis, elderly: Role of cytokines and metallothioneins.
2007
Abstract Background CD14 receptor is a mediator of the inflammatory response to bacterial products. A functional polymorphism in the promoter of the CD14 gene (CD14 C-260T) was associated with coronary heart disease and atherosclerosis albeit with conflicting data. Methods To better clarify the role of CD14 in atherosclerosis, we typed CD14 C-260T polymorphism in old Italian (Central of Italy) atherosclerotic patients with carotid stenosis related to lipid assessment, inflammation (soluble CD14, IL-6 serum levels) and IL-6, TNF-α, IL-10, Metallothioneins (MT) gene expressions in carotid plaques. Results There was an increased frequency of TT homozygotes in patients when compared to controls…
Presepsin and Midregional Proadrenomedullin in Pediatric Oncologic Patients with Febrile Neutropenia
2020
Abstract Objective In this study, we investigated the roles of presepsin (PSP) and midregional proadrenomedullin (mr-proADM) in children with febrile neutropenia (FN) due to chemotherapy. Methods We assessed 36 FN episodes in 26 children. Patients were classified into bacteremia (B) and fever of unknown origin (FUO) groups. We evaluated PSP and mr-proADM at admission (T0), after 24/48 h (T1), and after 5 days (T2). Results PSP and mr-proADM levels were elevated at T0 and significantly decreased at T2. mr-proADM levels did not significantly differ between the B and FUO groups. PSP levels significantly differed between the B and FUO groups only at T1. Both PSP and mr-proADM levels at T0 were …
The monocyte-macrophage system is affected in lysosomal storage diseases: an immunoelectron microscopic study
1997
Studying peripheral blood mononuclear cells (PBMCs) has become an important diagnostic tool in lysosomal storage diseases. Previous studies revealed that B and subclasses of T lymphocytes participate in the storage process, whereas the role of circulating monocytes was not clear. In this study, the involvement of CD14+ monocytes in lysosomal diseases was investigated. Blood samples from six patients with different lysosomal storage disorders were studied, including one with late--infantile and three with juvenile neuronal ceroid--lipofuscinoses, and two with mucopolysaccharidosis type VI. CD14+ cells were separated immunomagnetically from PBMCs and studied by light and electron microscopy. …
Expression of membrane C1q in human monocyte-derived macrophages is developmentally regulated and enhanced by interferon-γ
2001
The present study investigated when during "in vitro" maturation macrophages (MPhi) express membrane C1q (mC1q), and whether cell activation affects expression and function of mC1q. Although C1q mRNA was repeatedly detected in freshly isolated monocytes using reverse transcriptase-polymerase chain reaction, C1q protein was observed only in developing MPhi from day 1 to 4 on using immunodetection and flow cytometry. However, the quantity of mC1q and other MPhi membrane proteins differed strikingly in cells from different donors. We report here for the first time that CD14(+) and CD14(-) mC1q-bearing MPhi can develop, and that interferon-gamma increases mC1q display at the cell surface, and m…
Macrophage-mediated clearance of cells undergoing caspase-3-independent death
2003
Little is known of the functions of caspases in mediating the surface changes required for phagocytosis of dying cells. Here we investigate the role played by the effector caspase, caspase-3 in this process using the caspase-3-defective MCF-7 breast carcinoma line and derived caspase-3-expressing transfectants. Our results indicate that, while certain typical features of apoptosis induced by etoposide - namely classical morphological changes and the ability to degrade DNA into oligonucleosomal fragments - are caspase-3-dependent, loss of cell adhesion to plastic and the capacity to interact with, and to be phagocytosed by, human monocyte-derived macrophages - both by CD14-dependent and CD14…
Pore-forming toxins trigger shedding of receptors for interleukin 6 and lipopolysaccharide.
1996
Cleavage of membrane-associated proteins with the release of biologically active macromolecules is an emerging theme in biology. However, little is known about the nature and regulation of the involved proteases or about the physiological inducers of the shedding process. We here report that rapid and massive shedding of the interleukin 6 receptor (IL-6R) and the lipopolysaccharide receptor (CD14) occurs from primary and transfected cells attacked by two prototypes of pore-forming bacterial toxins, streptolysin O and Escherichia coli hemolysin. Shedding is not induced by an streptolysin O toxin mutant which retains cell binding capacity but lacks pore-forming activity. The toxin-dependent c…
Bipartite regulation of different components of the MHC class I antigen-processing machinery during dendritic cell maturation
2001
Dendritic cells (DC) are professional antigen-presenting cells (APC) which proceed from immature to a mature stage during their final differentiation. Immature DC are highly effective in terms of antigen uptake and processing, whereas mature DC become potent immunostimulatory cells. Until now, the expression profiles of the major components of the MHC class I antigen-processing machinery (APM) during DC development have not been well characterized. In this study, the mRNA and protein expression levels of the IFN-gamma inducible proteasome subunits, of the proteasome activators PA28, and of key components required for peptide transport and MHC class I-peptide complex assembly have been evalu…
Increased frequencies of CD11b+CD33+CD14+HLA-DRlowmyeloid-derived suppressor cells are an early event in melanoma patients
2014
Myeloid-derived suppressor cells (MDSC) are a heterogeneous cell population characterized by immunosuppressive activity. Elevated levels of MDSC in peripheral blood are found in inflammatory diseases as well as in malignant tumors where they are supposed to be major contributors to mechanisms of tumor-associated tolerance. We investigated the frequency and function of MDSC in peripheral blood of melanoma patients and observed an accumulation of CD11b(+) CD33(+) CD14(+) HLA-DR(low) MDSC in all stages of disease (I-IV), including early stage I patients. Disease progression and enhanced tumor burden did not result in a further increase in frequencies or change in phenotype of MDSC. By investig…