Search results for "Immune system"
showing 10 items of 2885 documents
Rapamycin and Zoledronic Acid strongly retard growth of advanced murine hepatocellular carcinoma via skewing and activation of innate and adaptive im…
2018
The presence of conifer resin decreases the use of the immune system in wood ants.
2008
5 pages; International audience; 1. Wood ants ( Formica paralugubris ) incorporate large amounts of solidified conifer resin into their nest, which reduces the density of many bacteria and fungi and protects the ants against some detrimental micro-organisms. By inducing an environment unfavourable to pathogens, the presence of resin may allow workers to reduce the use of their immune system. 2. The present study tested the hypothesis that the presence of resin decreases the immune activity of wood ants. Specifically, three components of the humoral immune defences of workers kept in resin-rich and resin-free experimental nests (antibacterial, lytic, and prophenoloxidase activities) were com…
Introduction. Ecological immunology.
2009
12 pages; International audience; An organism's fitness is critically reliant on its immune system to provide protection against parasites and pathogens. The structure of even simple immune systems is surprisingly complex and clearly will have been moulded by the organism's ecology. The aim of this review and the theme issue is to examine the role of different ecological factors on the evolution of immunity. Here, we will provide a general framework of the field by contextualizing the main ecological factors, including interactions with parasites, other types of biotic as well as abiotic interactions, intraspecific selective constraints (life-history trade-offs, sexual selection) and popula…
Should grape moth larval immunity help explaining resistance against natural enemies?
2011
National audience; In tritrophic systems (plants, phytophagous insects and natural enemies), host plant variation often keys the relative performance of both the herbivore and its associated natural enemies. In bottom-up effects, host plants could affect the fitness of phytophagous insects including growth rate and adult fertility. These effects are indirectly reflected in parasitoids whose success depends on their host quality. For instance, nutrient deficiency or/and toxic defensive compounds of the plants could slow-down the development of herbivorous insects, thus extending the window of vulnerability of attacks by natural enemies. The immune system is arguably the most common resistanc…
Some Plant Defense Stimulators can induce IL-1β production in human immune cells in vitro
2020
8 pages; International audience; Among Plant Protection Products (PPP), a new emerging category of pesticides act by stimulating plant defense in order to improve plant resistance against microbial pathogens. Given that these compounds, the so-called Plant Defense Stimulators (PDS) act on innate immunity, we tested, using an in vitro approach on human mononuclear leucocytes (PBMC), the potential toxicity (XTT assay) and inflammatory effects (production of IL-1β) of 4 PPP belonging to different chemical families. We found that two products (LBG-01F34® and Regalis®) did not induce any cytotoxicity or IL-1 β production. The product BION-50 WG®, that contains Acibenzolar-S-methyl (ASM) and sili…
'Immunogenetics of Aging': report on the activities of the 15th International HLA and Immunogenetics Working Group and 15th International HLA and Imm…
2011
'Immunogenetics of Aging' is a component that was first included in the 14th International HLA and Immunogenetics Workshop (IHIWS) and developed further within the 15th Workshop. The aim of this component was to assess the impact of human leukocyte antigen (HLA) genes, cytokine genes, and some innate immunity genes such as killer-cell immunoglobulin-like receptors (KIRs) and mannose-binding lectin 2 (MBL2) in successful aging and their contribution to the better understanding of immune dysfunction in old age. Within the 15th IHIWS new populations were included in the analysis. Additional cytokine gene polymorphisms were assessed and innate immunity genes were analyzed for possible relevance…
Extracellular Vesicles and Tumor-Immune Escape: Biological Functions and Clinical Perspectives
2020
The modulation of the immune system is one of the hallmarks of cancer. It is now widely described that cancer cells are able to evade the immune response and thus establish immune tolerance. The exploration of the mechanisms underlying this ability of cancer cells has always attracted the scientific community and is the basis for the development of new promising cancer therapies. Recent evidence has highlighted how extracellular vesicles (EVs) represent a mechanism by which cancer cells promote immune escape by inducing phenotypic changes on different immune cell populations. In this review, we will discuss the recent findings on the role of tumor-derived extracellular vesicles (TEVs) in re…
Molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system
2007
Although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. To explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (IBV), a prototype of Coronavirus and a well-characterized mucosal pathogen. Results showed that a number of innate immune factors including toll-like receptors (TLRs), retinoic-acid-inducible gene-1 (RIG-1), type I…
Increase in midgut microbiota load induces an apparent immune priming and increases tolerance to Bacillus thuringiensis
2010
Summary The insect immune system is comprised of both humoral and cellular components that are mobilized in response to parasitic or pathogenic infections. Activation of the immune response implies a consid- erable expenditure of energy and that is why insects rely on inducible pathways that are activated after coming into contact with the pathogenic agent. Known as immune priming, insects can prolong the activation of the immune response and transmit their immune status to the next generation. Starting from a laboratory colony of the lepidopteran Spodoptera exigua and using the lytic zone assay as a measure of the immune status, we selected for a sub-colony with high levels of immune activ…
Keyhole Limpet Haemocyanin in Experimental Bladder Cancer
2000
Objectives: Keyhole limpet haemocyanin (KLH) is a high-molecular-weight protein antigen collected from the haemolymph of the sea mollusk Megathura crenulata. It i