Search results for "IMMUNOLOGY"
showing 10 items of 9651 documents
Myeloperoxidase mediates neutrophil activation by association with CD11b/CD18 integrins.
2004
Recruitment and activation of polymorphonuclear neutrophils (PMNs) reflects a primary immunological response to invading pathogens and has also emerged as a hallmark of vascular inflammation. One of the principal enzymes released upon PMN activation is myeloperoxidase (MPO), a heme protein that not only generates cytotoxic oxidants but also impacts deleteriously on nitric oxide-dependent signaling cascades within the vasculature. Because MPO also associates with the membrane of PMN, we evaluated whether MPO could also function as an autocrine modulator of PMN activation. The extent of PMN membrane-associated MPO was elevated in patients with acute inflammatory vascular disease compared with…
C5a complement and cytokine signaling mediate the pronociceptive effects of complex regional pain syndrome patient IgM in fracture mice.
2020
It has been proposed that complex regional pain syndrome (CRPS) is a posttraumatic autoimmune disease. Previously, we observed that B cells contribute to CRPS-like changes in a mouse tibia fracture model, and that early (12 months duration) CRPS patient IgM antibodies have pronociceptive effects in the skin and spinal cord of muMT fracture mice lacking B cells. The current study evaluated the pronociceptive effects of intraplantar or intrathecal injections of early CRPS IgM (5 µg) in muMT fracture mice. Skin and lumbar spinal cord were collected for immunohistochemistry and polymerase chain reaction analyses. Wild-type mice exhibited postfracture increases in complement component C5a and it…
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…
Mesenchymal Stem Cells Provide Better Results Than Hematopoietic Precursors for the Treatment of Myocardial Infarction
2010
Objectives The purpose of this study was to compare the ability of human CD34(+) hematopoietic stem cells and bone marrow mesenchymal stem cells (MSC) to treat myocardial infarction (MI) in a model of permanent left descendent coronary artery (LDA) ligation in nude rats. Background Transplantation of human CD34(+) cells and MSC has been proved to be effective in treating MI, but no comparative studies have been performed to elucidate which treatment prevents left ventricular (LV) remodelling more efficiently. Methods Human bone marrow MSC or freshly isolated CD34(+) cells from umbilical cord blood were injected intramyocardially in infarcted nude rats. Cardiac function was analyzed by echoc…
Analytical model for the long- distance tracer-transport in plants
2011
International audience; Recent investigations of long-distance transport in plants using non-invasive tracer techniques such as C radiolabeling monitored by positron emission tomography (PET) combined with magnetic resonance imaging (MRI) revealed the need of dedicated methods to allow a quantitative data analysis and comparison of such experiments. A mechanistic compartmental tracer transport model is presented, defined by a linear system of partial differential equations (PDEs). This model simplifies the complexity of axial transport and lateral exchanges in the transport pathways of plants (e.g. the phloem) by simulating transport and reversible exchange within three compartments using j…
Microbiome: pro-inflammatory Prevotella?
2013
Rheumatoid arthritis (RA) is a prevalent systemic autoimmune disease, caused by a combination of genetic and environmental factors. Animal models suggest a role for intestinal bacteria in supporting the systemic immune response required for joint inflammation. Here we performed 16S sequencing on 114 stool samples from rheumatoid arthritis patients and controls, and shotgun sequencing on a subset of 44 such samples. We identified the presence of Prevotella copri as strongly correlated with disease in new-onset untreated rheumatoid arthritis (NORA) patients. Increases in Prevotella abundance correlated with a reduction in Bacteroides and a loss of reportedly beneficial microbes in NORA subjec…
Poly(I:C) and CpG-ODN combined aerosolization to treat lung metastases and counter the immunosuppressive microenvironment.
2015
The immunostimulatory ability of synthetic oligonucleotides containing CpG motifs (CpG-ODN), agonists of Toll-like receptor 9 (TLR9), can be harnessed to promote antitumor immunity by their application at the tumor site to stimulate local activation of innate immunity; however, particularly in the lung, tumor-associated immunosuppression can subvert such antitumor innate immune responses. To locally maintain continuous activation of innate subpopulations while inhibiting immunosuppressive cells, we evaluated aerosol delivery CpG-ODN combined with Poly(I:C), a TLR3 agonist able to convert tumor-supporting macrophages to tumoricidal effectors, in the treatment of B16 melanoma lung metastases …
How amniotic fluid shapes early odor-guided responses to colostrum and milk (and more)
2016
Revue; Among the multiple transitions that characterize mammalian development, birth certainly is the most abrupt and spectacular. It is also the most challenging for newborns when one considers their high mortality rates in any mammalian species. Although evolution has selected newborn organisms that possess the physiological and behavioral keys leading to adapt to this harsh psychobiological challenge, their capabilities cannot be considered separately from the maternal organism and the environment she creates. Mammalian females provide indeed passive (physiological) and/or active (behavioral) assistance to complement and boost their offspring’s capacities. One notable strategy of mammali…
Brain Opioid Activity and Oxidative Injury: Different Molecular Scenarios Connecting Celiac Disease and Autistic Spectrum Disorder
2020
Celiac Disease (CD) is an immune-mediated disease triggered by the ingestion of wheat gliadin and related prolamins from other cereals, such as barley and rye. Immunity against these cereal-derived proteins is mediated by pro-inflammatory cytokines produced by both innate and adaptive system response in individuals unable to adequately digest them. Peptides generated in this condition are absorbed across the gut barrier, which in these patients is characterized by the deregulation of its permeability. Here, we discuss a possible correlation between CD and Autistic Spectrum Disorder (ASD) pathogenesis. ASD can be induced by an excessive and inappropriate brain opioid activity during the neon…
The Role of Fc Receptors on the Effectiveness of Therapeutic Monoclonal Antibodies.
2021
Since the approval of the first monoclonal antibody (mAb) in 1986, a huge effort has been made to guarantee safety and efficacy of therapeutic mAbs. As of July 2021, 118 mAbs are approved for the European market for a broad range of clinical indications. In order to ensure clinical efficacy and safety aspects, (pre-)clinical experimental approaches evaluate the respective modes of action (MoA). In addition to antigen-specificity including binding affinity and -avidity, MoA comprise Fc-mediated effector functions such as antibody dependent cellular cytotoxicity (ADCC) and the closely related antibody dependent cellular phagocytosis (ADCP). For this reason, a variety of cell-based assays have…