Search results for "Innate"
showing 10 items of 638 documents
Mast cells are crucial for early inflammation, migration of Langerhans cells, and CTL responses following topical application of TLR7 ligand in mice.
2007
Abstract Until recently, IgE-activated mast cells have been regarded merely as effector cells of adaptive immune responses, involved in allergic reactions and mucosal immunity to parasites. Herein, we report that murine dermal mast cells, activated by local administration of a cream containing the synthetic TLR7 ligand imiquimod, are essential to initiate an early inflammatory reaction. The mast-cell–derived cytokines TNF-α and IL-1β play an important role in this process. Furthermore, TLR7-activated mast cells are also able to promote the emigration of Langerhans cells, which partly depends on the expression of mast-cell–derived IL-1β. We have previously shown that TLR7 ligation enhances t…
Functional C1-inhibitor diagnostics in hereditary angioedema: Assay evaluation and recommendations
2008
Hereditary angioedema (HAE) is an autosomal dominant disease characterized by recurrent episodes of potentially life-threatening angioedema. The most widespread underlying genetic deficiency is a heterozygous deficiency of the serine protease inhibitor Cl esterase inhibitor (C1-Inh). In addition to low C4 levels, the most important laboratory parameter for correct diagnosis of HAE or angioedema due to acquired C1-Inh deficiency is reduced C1-Inh function (fC1-Inh). No direct recommendations about the assays for fC1-Inh or sample handling conditions are available, although this would prove especially useful when a laboratory first starts to offer assays on fC1-Inh for HAE diagnosis. In the p…
Mast Cells Are Key Promoters of Contact Allergy that Mediate the Adjuvant Effects of Haptens
2011
SummaryA prominent feature of sensitizing environmental compounds that cause allergic contact dermatitis is the rapid induction of an innate inflammatory response that seems to provide danger signals for efficient T cell priming. We generated mouse models of mast cell deficiency, mast cell-specific gene inactivation, and mast cell reporter mice for intravital imaging and showed that these adjuvant effects of contact allergens are mediated by mast cells and histamine. Mast cell deficiency resulted in impaired emigration of skin DCs to the lymph node and contact hypersensitivity was dramatically reduced in the absence of mast cells. In addition, mast cell-specific inactivation of the Il10 gen…
Immunosenescence, inflammation and Alzheimer’s disease
2012
Abstract Ageing impacts negatively on the development of the immune system and its ability to fight pathogens. Progressive changes in the T-cell and B-cell systems over the lifespan of individuals have a major impact on the capacity to respond to immune challenges. The cumulative age-associated changes in immune competence are termed immunosenescence that is characterized by changes where adaptive immunity deteriorates, while innate immunity is largely conserved or even upregulated with age. On the other hand, ageing is also characterized by “inflamm-ageing”, a term coined to explain the inflammation commonly present in many age-associated diseases. It is believed that immune inflammatory p…
Specific Detection and Localization of Microsporidian Parasites in Invertebrate Hosts by Using In Situ Hybridization
2013
ABSTRACT We designed fluorescence in situ hybridization probes for two distinct microsporidian clades and demonstrated their application in detecting, respectively, Nosema / Vairimorpha and Dictyoceola species. We used them to study the vertical transmission of two microsporidia infecting the amphipod Gammarus duebeni .
What is the physiological function of mast cells?
2003
Under physiological conditions, skin mast cells preferentially localize around nerves, blood vessels and hair follicles. This observation, which dates back to Paul Ehrlich, intuitively suggests that these enigmatic, multifacetted protagonists of natural immunity are functionally relevant to many more aspects of tissue physiology than just to the generation of inflammatory and vasodilatory responses to IgE-dependent environmental antigens. And yet, for decades, mainstream-mast cell research has been dominated by a focus on the -undisputedly prominent and important - mast cell functions in type I immune responses and in the pathogenesis and management of allergic diseases. Certainly, it is ha…
Exploring a regulatory role for mast cells: 'MCregs'?
2010
Regulatory cells can mould the fate of the immune response by direct suppression of specific subsets of effector cells, or by redirecting effectors against invading pathogens and infected or neoplastic cells. These functions have been classically, although not exclusively, ascribed to different subsets of T cells. Recently, mast cells have been shown to regulate physiological and pathological immune responses, and thus to act at the interface between innate and adaptive immunity assuming different functions and behaviors at discrete stages of the immune response. Here, we focus on these poorly defined, and sometimes apparently conflicting, functions of mast cells.
Complement and atherosclerosis—united to the point of no return?
2012
Atherosclerosis is widely regarded as a chronic inflammatory disease that develops as a consequence of entrapment of oxidized low-density lipoprotein (LDL) in the arterial intima and its interaction with components of both innate and adaptive immunity. This article reviews the role of the complement system in the context of a different concept on atherogenesis. Arguments are forwarded in support of the contention that enzymatic and not oxidative modification of LDL is the prerequisite for transforming the lipoprotein into a moiety that is recognized by the innate immune system. In a departure from general wisdom, it is proposed that these processes are initially not pathological. To the con…
Invertebrate Models in Innate Immunity and Tissue Remodeling Research
2022
The aim of this Special Issue is to highlight the close functional and highly conserved link between innate immunity, homeostasis maintenance, inflammation, tissue remodeling and regeneration [...]
Inflammatory Response of the Ascidian Ciona intestinalis
2016
Abstract The Ciona intestinalis inflammatory response to several irritants appears to be composed of a complex reaction set. The cellular reactions in the tunic involve hemocyte infiltration, hemocyte and epidermis activities, vacuolization, and cell disruption, while cell products can contribute to form capsule components and/or cause a tunic wound. In this response, the involvement of the pharynx, as the main immune-competent organ, has been disclosed by a lipopolysaccharide challenge that upregulates innate immunity genes and transcription activation genes. The pharynx responds through hemocyte recruitment into the pharynx vessels, enhancement of galectin-like lectins in the serum hemoly…