Cytokines are small proteins that are critical for controlling the growth and activity of hematopoietic cells by binding to cell surface receptors and transmitting signals across membranes. The β common (βc) cytokine receptor family, consisting of the granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-3, and IL-5 cytokine receptors, is an architype of the heterodimeric cytokine receptor systems. We now know that signaling by cytokine receptors is not always an "all or none" phenomenon.
View Article and Find Full Text PDFJ Allergy Clin Immunol
August 2024
Background: Polyethylene glycol (PEG) is a nonprotein polymer that is present in its native (unbound) form as an excipient in a range of products. It is increasingly being utilized clinically in the form of PEGylated liposomal medications and vaccines. PEG is the cause of anaphylaxis in a small percentage of drug reactions; however, diagnosis of PEG allergy is complicated by the variable and poor diagnostic performance of current skin testing protocols.
View Article and Find Full Text PDFJ Allergy Clin Immunol
March 2024
Background: Patients with severe asthma can present with eosinophilic type 2 (T2), neutrophilic, or mixed inflammation that drives airway remodeling and exacerbations and represents a major treatment challenge. The common β (βc) receptor signals for 3 cytokines, GM-CSF, IL-5, and IL-3, which collectively mediate T2 and neutrophilic inflammation.
Objective: To determine the pathogenesis of βc receptor-mediated inflammation and remodeling in severe asthma and to investigate βc antagonism as a therapeutic strategy for mixed granulocytic airway disease.
A memory engram is thought to be the physical substrate of the memory trace within the brain, which is generally depicted as a neuronal ensemble activated by learning to fire together during encoding and retrieval. It has been postulated that engram cell ensembles are functionally interconnected across multiple brain regions to store a single memory as an "engram complex", but visualizing this engram complex across the whole brain has for long been hindered by technical limitations. With the recent development of tissue clearing techniques, advanced light-sheet microscopy, and automated 3D image analysis, it has now become possible to generate a brain-wide map of engram cells and thereby to visualize the "engram complex".
View Article and Find Full Text PDFJ Allergy Clin Immunol
September 2023
Background: Mast cells (MCs) are tissue-resident immune cells that mediate IgE-dependent allergic responses. Downstream of FcεRI, an intricate network of receptor-specific signaling pathways and adaptor proteins govern MC function. The 14-3-3 family of serine-threonine phosphorylation-dependent adapter proteins are known to organize intracellular signaling.
View Article and Find Full Text PDFJ Allergy Clin Immunol
February 2023
The family of cytokines that comprises IL-3, IL-5, and GM-CSF was discovered over 30 years ago, and their biological activities and resulting impact in clinical medicine has continued to expand ever since. Originally identified as bone marrow growth factors capable of acting on hemopoietic progenitor cells to induce their proliferation and differentiation into mature blood cells, these cytokines are also recognized as key mediators of inflammation and the pathobiology of diverse immunologic diseases. This increased understanding of the functional repertoire of IL-3, IL-5, and GM-CSF has led to an explosion of interest in modulating their functions for clinical management.
View Article and Find Full Text PDFAllergic contact dermatitis (ACD) is a prevalent and poorly controlled inflammatory disease caused by skin infiltration of T cells and granulocytes. The beta common (β) cytokines GM-CSF, IL-3, and IL-5 are powerful regulators of granulocyte function that signal through their common receptor subunit β, a property that has made β an attractive target to simultaneously inhibit these cytokines. However, the species specificity of β has precluded testing of inhibitors of human β in mouse models.
View Article and Find Full Text PDFMast cells (MC)s are evolutionarily conserved, tissue-resident immune cells with diverse roles in allergy, cancer, and protection from infection by helminths and microorganisms. The significant diversity in MC development and tissue-specific functional characteristics has recently begun to be understood. Exciting developments in single-cell-based RNA, protein, and chromatin profiling technologies offer new opportunities to characterize MC heterogeneity and to uncover novel MC functions and subtypes; these developments might lead to new and clinically effective therapies for certain pathologies.
View Article and Find Full Text PDFObjectives/hypothesis: The efficacy of short-term oral corticosteroids in chronic rhinosinusitis without nasal polyps (CRSsNP) is unknown. The aim of this controlled study was to assess the immediate and long-term outcomes from a short course of a commonly used oral corticosteroid, prednisolone, in well-defined CRSsNP patients.
Study Design: Prospective, observational controlled study.
Mast cells (MCs) are versatile immune cells capable of rapidly responding to a diverse range of extracellular cues. Here, we mapped the genomic and transcriptomic changes in human MCs upon diverse stimuli. Our analyses revealed broad H3K4me3 domains and enhancers associated with activation.
View Article and Find Full Text PDFInvariant and semi-invariant T cells are emerging as important regulators of host environment interactions at barrier tissues such as the airway and skin. In contrast to conventional T cells, invariant natural killer T (iNKT) cells and mucosal associated invariant T (MAIT) cells express T cell receptors of very limited diversity. iNKT and MAIT cells recognise antigens presented by the MHC class 1-like monomorphic molecules CD1d and MR1, respectively.
View Article and Find Full Text PDFBackground: Natural killer T (NKT) cells express a T-cell receptor that recognizes endogenous and environmental glycolipid antigens. Several subsets of NKT cells have been identified, including IFN-γ-producing NKT1 cells, IL-4-producing NKT2 cells, and IL-17-producing NKT17 cells. However, little is known about the factors that regulate their differentiation and respective functions within the immune system.
View Article and Find Full Text PDFCross-linkage of the high-affinity immunoglobulin E (IgE) receptor (FcɛRI) on mast cells by antigen ligation has a critical role in the pathology of IgE-dependent allergic disorders, such as anaphylaxis and asthma. Restraint of intracellular signal transduction pathways that promote release of mast cell-derived pro-inflammatory mediators is necessary to dampen activation and restore homoeostasis. Here we show that the ligase Nedd4-2 and the adaptor Ndfip1 (Nedd4 family interacting protein 1) limit the intensity and duration of IgE-FcɛRI-induced positive signal transduction by ubiquitinating phosphorylated Syk, a tyrosine kinase that is indispensable for downstream FcɛRI signalosome activity.
View Article and Find Full Text PDFMast cells are pivotal in the pathogenesis of allergy and inflammation. In addition to the classical IgE-dependent mechanism involving crosslinking of the high-affinity receptor for IgE (FcεRI), mast cells are also activated by Toll-like receptors (TLRs) which are at the center of innate immunity. In this study, we demonstrated that the response of LAD2 cells (a human mast cell line) to anti-IgE was altered in the presence of the TLR2 agonists peptidoglycan (PGN) and tripalmitoyl-S-glycero-Cys-(Lys)4 (Pam3CSK4).
View Article and Find Full Text PDFObjectives: Mast cells are believed to contribute to the pathogenesis of osteoporosis as their number is increased in osteoporotic bones. Herba Epimedii, Fructus Ligustri Lucidi and Fructus Psoraleae are three Chinese herbs traditionally for tonifying the 'kidney system' and a herbal formula (ELP) containing the respective herbs at the weight ratio of 5 : 4 : 1 was shown to prevent osteoporosis. This study evaluated if suppression of mast cell accumulation and activity contribute to the anti-osteoporotic action of ELP.
View Article and Find Full Text PDFType 2 immunity is critical for defense against cutaneous infections but also underlies the development of allergic skin diseases. We report the identification in normal mouse dermis of an abundant, phenotypically unique group 2 innate lymphoid cell (ILC2) subset that depended on interleukin 7 (IL-7) and constitutively produced IL-13. Intravital multiphoton microscopy showed that dermal ILC2 cells specifically interacted with mast cells, whose function was suppressed by IL-13.
View Article and Find Full Text PDFWe have previously demonstrated that exogenous nitric oxide (NO) inhibited anti-IgE-mediated histamine release from human cultured mast cells. In the current study, we further investigated if syntheses of eicosanoids and cytokines were also suppressed by NO donors and evaluated if activation of soluble guanylyl cyclase (sGC) was an underlying mechanism. The effects of the NO donor diethylamine NONOate (DEA/NO) on IgE-dependent syntheses of eicosanoids (prostaglandin D(2) and cysteinyl leukotrienes) and cytokines (tumor necrosis factor-alpha and interleukin-8) from buffy coat derived human cultured mast cells were examined.
View Article and Find Full Text PDFThe mast cells have been suggested to be a cellular source of nitric oxide (NO) which level is increased in the pathogenesis of asthma. However, isoforms of the NO generating enzyme, nitric oxide synthase (NOS), in primary human mast cells have not been defined due to the lack of a suitable model. We hence examined directly the expression of NOS mRNA and proteins in primary human cultured mast cells (HCMC).
View Article and Find Full Text PDFMast cells are important effector cells of allergy and techniques for culturing human mast cells have been developed in recent years. In the current investigation, we studied the phenotypic and functional characteristics of mast cells cultured from adult human peripheral blood mononuclear cells. Mature human mast cells were obtained by first culturing mononuclear cells in methylcellulose containing stem cell factor (SCF), IL-3 and IL-6 for six weeks and subsequently in liquid medium containing SCF and IL-6 for another six weeks.
View Article and Find Full Text PDFBackground: In 2003 the National Institute of Clinical Excellence published guidelines recommending the use of brain natriuretic peptide (BNP) and the electrocardiogram (ECG) as part of the diagnostic work up of individuals with heart failure. However, the guideline did not address whether one test was superior to the other or whether performing both tests was superior to performing single tests.
Aim: To investigate the relative test accuracy of the ECG, BNP, N terminal-pro brain natriuretic peptide (NT-proBNP) and combinations of two or more tests in the diagnosis of left ventricular systolic dysfunction (LVSD) in the primary care setting.
Little is known about the effects of ageing on cerebral autoregulation (CA). To examine the relationship between age and CA in adults, we conducted a prospective study using a non-invasive protocol without external stimuli. We studied 32 subjects, aged 23-68 years.
View Article and Find Full Text PDFA moving correlation index (Mx-ABP) between arterial blood pressure (ABP) and mean middle cerebral artery blood flow velocity (CBFV) can be used to monitor dynamic cerebrovascular autoregulation (CA) after traumatic brain injury (TBI). In this study we examined hemispheric CA asymmetry and temporal CA profiles, their relationship with ABP and CBFV, and their prognostic relevance. Mx-ABP was calculated for each hemisphere in 25 TBI patients second-daily for as long as they were receiving sedation and analgesia.
View Article and Find Full Text PDFA moving correlation index (Mx-CPP) of cerebral perfusion pressure (CPP) and mean middle cerebral artery blood flow velocity (CBFV) allows continuous monitoring of dynamic cerebral autoregulation (CA) in patients with severe traumatic brain injury (TBI). In this study we validated Mx-CPP for TBI, examined its prognostic relevance, and assessed its relationship with arterial blood pressure (ABP), CPP, intracranial pressure (ICP), and CBFV. We tested whether using ABP instead of CPP for Mx calculation (Mx-ABP) produces similar results.
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