β-(1,3)-Glucan is present in mould cell walls and frequently detected in house dust mite (HDM) faeces. β-Glucan exposure is thought to be associated with pulmonary allergic inflammation in mouse and man, although the published data are inconsistent. Here, we show that highly purified β-glucan exacerbates HDM-induced eosinophilic, T helper 2 type airway responses by acting as an adjuvant, promoting activation, proliferation and polarisation of HDM-specific T cells (1-Derβ T cells).
View Article and Find Full Text PDFTissue-resident macrophages can derive from yolk sac macrophages (YS-Macs), fetal liver monocytes (FL-MOs), or adult bone-marrow monocytes (BM-MOs). The relative capacity of these precursors to colonize a niche, self-maintain, and perform tissue-specific functions is unknown. We simultaneously transferred traceable YS-Macs, FL-MOs, and BM-MOs into the empty alveolar macrophage (AM) niche of neonatal Csf2rb(-/-) mice.
View Article and Find Full Text PDFMeDALL (Mechanisms of the Development of ALLergy; EU FP7-CP-IP; Project No: 261357; 2010-2015) has proposed an innovative approach to develop early indicators for the prediction, diagnosis, prevention and targets for therapy. MeDALL has linked epidemiological, clinical and basic research using a stepwise, large-scale and integrative approach: MeDALL data of precisely phenotyped children followed in 14 birth cohorts spread across Europe were combined with systems biology (omics, IgE measurement using microarrays) and environmental data. Multimorbidity in the same child is more common than expected by chance alone, suggesting that these diseases share causal mechanisms irrespective of IgE sensitization.
View Article and Find Full Text PDFChronic mucocutaneous or invasive fungal infections are generally the result of primary or secondary immune dysfunction. Patients with autosomal recessive CARD9 mutations are also predisposed to recurrent mucocutaneous and invasive fungal infections with Candida spp., dermatophytes (e.
View Article and Find Full Text PDFA20 negatively regulates multiple inflammatory signalling pathways. We here addressed the role of A20 in club cells (also known as Clara cells) of the bronchial epithelium in their response to influenza A virus infection. Club cells provide a niche for influenza virus replication, but little is known about the functions of these cells in antiviral immunity.
View Article and Find Full Text PDFSelf-renewing tissue-resident macrophages are thought to be exclusively derived from embryonic progenitors. However, whether circulating monocytes can also give rise to such macrophages has not been formally investigated. Here we use a new model of diphtheria toxin-mediated depletion of liver-resident Kupffer cells to generate niche availability and show that circulating monocytes engraft in the liver, gradually adopt the transcriptional profile of their depleted counterparts and become long-lived self-renewing cells.
View Article and Find Full Text PDFAlthough the field of cancer immunotherapy is intensively investigated, there is still a need for generic strategies that allow easy, mild and efficient formulation of vaccine antigens. Here we report on a generic polymer-protein ligation strategy to formulate protein antigens into reversible polymeric conjugates for enhanced uptake by dendritic cells and presentation to CD8 T-cells. A N-hydroxypropylmethacrylamide (HPMA)-based copolymer was synthesized via RAFT polymerization followed by introduction of pyridyldisulfide moieties.
View Article and Find Full Text PDFSerological monitoring is a feature of surveillance programmes for the detection of the circulation of notifiable low pathogenic avian influenza (LPAI) viruses in commercial poultry holdings. Commercial multispecies nucleoprotein (NP) enzyme-linked immunosorbent assays (ELISAs) have been replacing the haemagglutination inhibition (HI) test as pre-screening tools. Few comparative studies have been conducted to test sera from domestic ducks for diagnostic purposes.
View Article and Find Full Text PDFRecent evidence points at an important role of endogenous cell-damage induced pro-inflammatory molecules in the generation of epileptic seizures. Uric acid, under the form of monosodium urate crystals, has shown to have pro-inflammatory properties in the body, but less is known about its role in seizure generation. This study aimed to unravel the contribution of uric acid to seizure generation in a mouse model for acute limbic seizures.
View Article and Find Full Text PDFChildhood asthma is typically associated with a polarized Th2 response to inhaled allergens and is influenced by genetics. Yang et al. show that the asthma susceptibility gene DENND1B controls cytokine production in Th2 lymphocytes by controlling the rate of TCR internalization and routing to endosomes, providing a molecular basis for how DENND1B contributes to asthma pathogenesis.
View Article and Find Full Text PDFNanomaterials hold potential of altering the interaction between therapeutic molecules and target cells or tissues. High aspect ratio nanomaterials in particular have been reported to possess unprecedented properties and are intensively investigated for their interaction with biological systems. Graphene oxide (GOx) is a water-soluble graphene derivative that combines high aspect ratio dimension with functional groups that can be exploited for bioconjugation.
View Article and Find Full Text PDFSurveillance of notifiable avian influenza (NAI) virus is mandatory in European member states, and each year a serological survey is performed to detect H5 and H7 circulation in poultry holdings. In Belgium, this serological monitoring is a combination of a stratified and a risk-based approach and is applied to commercial holdings with more than 200 birds. Moreover, a competitive nucleoprotein (NP) ELISA has been used as first screening method since 2010.
View Article and Find Full Text PDFHomosubtypic and heterosubtypic immunity in mallards (Anas platyrhynchos) play an important role in the avian influenza virus (AIV) diversity. The mechanisms of AIV replication among wild birds and the role of immunity in AIV diversity have thus not been completely clarified. During the monitoring of AI circulation among wild waterfowl in 2007-2008, two viruses (H3N8 and H1N1) were isolated from ducks caught in a funnel trap located in La Hulpe wetland in Belgium.
View Article and Find Full Text PDFBackground: Human respiratory syncytial virus (RSV) is a frequent cause of asthma exacerbations, yet the susceptibility of asthmatic patients to RSV is poorly understood.
Objective: We sought to address the contribution of resident alveolar macrophages (rAMs) to susceptibility to RSV infection in mice that recovered from allergic airway eosinophilia.
Methods: Mice were infected with RSV virus after clearance of allergic airway inflammation (AAI).
Lineage 2 West Nile virus (WNV) strains were reported for the first time in Europe in 2004. Despite an almost silent circulation around their entry point in Hungary, an upsurge of pathogenicity occurred in 2010 as 262 people suffered from neuroinvasive disease in Greece. This increase in virulence was imputed to the emergence of a His249Pro mutation in the viral NS3 helicase, as previously evidenced in American crows experimentally infected with the prototype lineage 1 North-American WNV strain.
View Article and Find Full Text PDFNatural killer (NK) cell maturation is a tightly controlled process that endows NK cells with functional competence and the capacity to recognize target cells. Here, we found that the transcription factor (TF) Zeb2 was the most highly induced TF during NK cell maturation. Zeb2 is known to control epithelial to mesenchymal transition, but its role in immune cells is mostly undefined.
View Article and Find Full Text PDFRenal cell carcinoma (RCC) is an immunogenic tumor, but uses several immune-suppressive mechanisms to shift the balance from tumor immune response toward tumor growth. Although RCC has traditionally been considered to be radiation resistant, recent evidence suggests that hypofractionated radiotherapy contributes to systemic antitumor immunity. Because the efficacy of antitumor immune responses depends on the complex balance between diverse immune cells and progressing tumor cells, radiotherapy alone is unlikely to induce persistent antitumor immunity.
View Article and Find Full Text PDFThe Flow Cytometry: Critical Assessment of Population Identification Methods (FlowCAP) challenges were established to compare the performance of computational methods for identifying cell populations in multidimensional flow cytometry data. Here we report the results of FlowCAP-IV where algorithms from seven different research groups predicted the time to progression to AIDS among a cohort of 384 HIV+ subjects, using antigen-stimulated peripheral blood mononuclear cell (PBMC) samples analyzed with a 14-color staining panel. Two approaches (FlowReMi.
View Article and Find Full Text PDFBackground: The lack of seasonality of swine influenza A virus (swIAV) in combination with the capacity of swine to harbor a large number of co-circulating IAV lineages, resulting in the risk for the emergence of influenza viruses with pandemic potential, stress the importance of swIAV surveillance. To date, active surveillance of swIAV worldwide is barely done because of the short detection period in nasal swab samples. Therefore, more sensitive diagnostic methods to monitor circulating virus strains are requisite.
View Article and Find Full Text PDFBackground: Impaired regulatory T cell (Treg) function is thought to contribute to ongoing inflammatory responses in sarcoidosis, but underlying mechanisms remain unclear. Moreover, it is not known if increased apoptotic susceptibility of Tregs may contribute to an impaired immunosuppressive function in sarcoidosis. Therefore, the aim of this study is to analyze proportions, phenotype, survival, and apoptotic susceptibility of Tregs in sarcoidosis.
View Article and Find Full Text PDFImmunity to Influenza A virus (IAV) is controlled by conventional TCRαβ(+) CD4(+) and CD8(+) T lymphocytes, which mediate protection or cause immunopathology. Here, we addressed the kinetics, differentiation, and antigen specificity of CD4(-)CD8(-) double-negative (DN) T cells. DNT cells expressed intermediate levels of TCR/CD3 and could be further divided in γδ T cells, CD1d-reactive type I NKT cells, NK1.
View Article and Find Full Text PDFTo further investigate the contribution of intercellular adhesion molecule-1 (ICAM-1) to adaptive immune responses, we analysed T-cell development and function in mice lacking full-length ICAM-1 (ICAM-1(tm1Jcgr) ). Compared with wild-type (ICAM-1(WT) ) mice, ICAM-1(tm1Jcgr) mice have impaired thymocyte development. Proportions and numbers of double negative, double positive, mature CD4(+) and CD8(+) thymocytes, as well as of regulatory T (Treg) cells were also significantly decreased.
View Article and Find Full Text PDFGrowing up on a dairy farm protects children from allergy, hay fever, and asthma. A mechanism linking exposure to this endotoxin (bacterial lipopolysaccharide)-rich environment with protection has remained elusive. Here we show that chronic exposure to low-dose endotoxin or farm dust protects mice from developing house dust mite (HDM)-induced asthma.
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