Search results for "IMM"

Echinodermata: The complex immune system in echinoderms

2018

View references (418) The Echinodermata are an ancient phylum of benthic marine invertebrates with a dispersal-stage planktonic larva. These animals have innate immune systems characterized initially by clearance of foreign particles, including microbes, from the body cavity of both larvae and adults, and allograft tissue rejection in adults. Immune responsiveness is mediated by a variety of adult coelomocytes and larval mesenchyme cells. Echinoderm diseases from a range of pathogens can lead to mass die-offs and impact aquaculture, but some individuals can recover. Genome sequences of several echinoderms have identified genes with immune function, including expanded families of Toll-like r…

EBI2 in splenic and local immune responses and in autoimmunity

2017

Abstract The seven transmembrane G protein-coupled receptor EBV-induced gene 2 (EBI2), also known as GPR183, is expressed in particular in immune cells. Activated by its endogenous ligands, which are a group of oxysterols, it functions as a chemo-attractant receptor, mediating cell migration. In coordination with other receptors, EBI2 plays important roles in controlling the migration of immune cells during the course of a T-dependent Ab response in the spleen. In recent years, it has become clear that EBI2 also has other roles to play in the immune system. Thus, EBI2 seems to be involved in innate immune responses, such as those mediated by TLR signaling, and it has been implicated in regi…

2018

The IgMi mouse fails to secrete antibodies or class switch its BCR from IgM. Our study reveals that other cellular compartments, including B-cell subsets, DC subsets, GC B cells and TFH cells are perturbed in the IgMi mouse, thus presenting important additional considerations when using the mouse to explore the role of secreted antibody.

Analysis of the prognostic role of an immune checkpoint score in resected non-small cell lung cancer patients

2016

[EN] Tumors develop mechanisms to recruit tolerogenic immune cells and to induce the expression of molecules that act as immune checkpoints. This regulation of the immune microenvironment favors immune tolerance to the neoplastic cells. In this study, we have investigated the prognostic role of immune-checkpoint expression markers in a cohort of resectable non-small cell lung cancer (NSCLC) patients. RNA was isolated from fresh-frozen lung specimens (tumor and normal lung) (n = 178). RTqPCR was performed to analyze the relative expression of 20 immune-related genes that were normalized by the use of endogenous genes selected by GeNorm algorithm. Patients with higher expression levels of IL2…

Targeting cellular fatty acid synthesis limits T helper and innate lymphoid cell function during intestinal inflammation and infection

2019

CD4+ T cells contribute critically to a protective immune response during intestinal infections, but have also been implicated in the aggravation of intestinal inflammatory pathology. Previous studies suggested that T helper type (Th)1 and Th17 cells depend on de novo fatty acid (FA) synthesis for their development and effector function. Here, we report that T-cell-specific targeting of the enzyme acetyl-CoA carboxylase 1 (ACC1), a major checkpoint controlling FA synthesis, impaired intestinal Th1 and Th17 responses by limiting CD4+ T-cell expansion and infiltration into the lamina propria in murine models of colitis and infection-associated intestinal inflammation. Importantly, pharmacolog…

Rheostatic Functions of Mast Cells in the Control of Innate and Adaptive Immune Responses

2017

Mast cells are evolutionarily ancient cells, endowed with a unique developmental, phenotypic, and functional plasticity. They are resident cells that participate in tissue homeostasis by constantly sampling the microenvironment. As a result of their large repertoire of receptors, they can respond to multiple stimuli and selectively release different types and amounts of mediator. Here, we present and discuss the recent mast cell literature, focusing on studies that demonstrate that mast cells are more than a switch that is turned ‘off’ when in the resting state and ‘on’ when in the degranulating state. We propose a new vision of mast cells in which, by operating in a ‘rheostatic 

Extravascular coagulation in hematopoietic stem and progenitor cell regulation

2018

Abstract The hemostatic system plays pivotal roles in injury repair, innate immunity, and adaptation to inflammatory challenges. We review the evidence that these vascular-protective mechanisms have nontraditional roles in hematopoietic stem cell (HSC) maintenance in their physiological bone marrow (BM) niches at steady-state and under stress. Expression of coagulation factors and the extrinsic coagulation initiator tissue factor by osteoblasts, tissue-resident macrophages, and megakaryocytes suggests that endosteal and vascular HSC niches are functionally regulated by extravascular coagulation. The anticoagulant endothelial protein C receptor (EPCR; Procr) is highly expressed by primitive …

MUC4 is overexpressed in idiopathic pulmonary fibrosis and collaborates with transforming growth factor β inducing fibrotic responses.

2021

Several mucins are implicated in idiopathic pulmonary fibrosis (IPF); however, there is no evidence regarding the role of MUC4 in the development of IPF. Here we demonstrated that MUC4 was overexpressed in IPF patients (n = 22) compared with healthy subjects (n = 21) and located in pulmonary arteries, bronchial epithelial cells, fibroblasts, and hyperplastic alveolar type II cells. Decreased expression of MUC4 using siRNA–MUC4 inhibited the mesenchymal/myofibroblast transformations of alveolar type II A549 cells and lung fibroblasts, as well as cell senescence and fibroblast proliferation induced by TGF-β1. The induction of the overexpression of MUC4 increased the effects of TGF-β1 on mesen…

Danger signals: Chemotherapy enhancers?

2017

IF 9.614; International audience; Endogenous danger signals are molecules normally present in a given cell compartment that are rapidly released following cell stress and induce immune responses. We and others have shown that dying tumor cells treated with some chemotherapies are able to induce anticancer immune responses, which rely on their release of danger signals such as the nuclear protein HMGB1. DNA can also be released from chemotherapy-treated tumor cells, act as a danger signal, and boost anticancer immunity. While the immunostimulatory properties of DNA have been identified for decades, the recent discovery of a novel family of receptors, cytosolic DNA sensors, has provided a nov…

NKG2D stimulation of CD8(+) T cells during priming promotes their capacity to produce cytokines in response to viral infection in mice

2017

NKG2D is an activating receptor that is expressed on most cytotoxic cells of the immune system, including NK cells, γδ and CD8+ T cells. It is still a matter of debate whether and how NKG2D mediates priming of CD8+ T cells in vivo, due to a lack of studies where NKG2D is eliminated exclusively in these cells. Here we studied the impact of NKG2D on effector CD8+ T-cell formation. NKG2D-deficiency that is restricted to murine CD8+ T cells did not impair antigen-specific T-cell expansion following mCMV and LCMV infection, but reduced their capacity to produce cytokines. Upon infection, conventional dendritic cells induce NKG2D ligands, which drive cytokine production on CD8+ T cells via the Da…