T-cell recognition is shaped by epitope sequence conservation in the host proteome and microbiome

Several mechanisms exist to avoid or suppress inflammatory T-cell immune responses that could prove harmful to the host due to targeting self-antigens or commensal microbes. We hypothesized that these mechanisms could become evident when comparing the immunogenicity of a peptide from a pathogen or allergen with the conservation of its sequence in the human proteome or the healthy human microbiome. Indeed, performing such comparisons on large sets of validated T-cell epitopes, we found that epitopes that are similar with self-antigens above a certain threshold showed lower immunogenicity, presumably as a result of negative selection of T cells capable of recognizing such peptides. Moreover, we also found a reduced level of immune recognition for epitopes conserved in the commensal microbiome, presumably as a result of peripheral tolerance. These findings indicate that the existence (and potentially the polarization) of T-cell responses to a given epitope is influenced and to some extent predictable based on its similarity to self-antigens and commensal antigens.Fil: Bresciani, Anne Gøther. Technical University of Denmark; Dinamarca. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Paul, Sinu. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Schommer, Nina. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Dillon, Myles B.. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Bancroft, Tara. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Greenbaum, Jason. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Sette, Alessandro. La Jolla Institute for Allergy and Immunology; Estados UnidosFil: Nielsen, Morten. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas ; Argentina. Technical University of Denmark; DinamarcaFil: Peters, Bjoern. La Jolla Institute for Allergy and Immunology; Estados Unido

Satellite-assisted monitoring of water quality to support the implementation of the Water Framework Directive

The EU Water Framework Directive1 (WFD) is an ambitious legislation framework to achieve good ecological and chemical status for all surface waters and good quantitative and chemical status for groundwater by 2027. A total of 111,062 surface waterbodies are presently reported on under the Directive, 46% of which are actively monitored for ecological status. Of these waterbodies 80% are rivers, 16% are lakes, and 4% are coastal and transitional waters. In the last assessment, 4% (4,442) of waterbodies still had unknown ecological status, while in 23% monitoring did not include in situ water sampling to support ecological status assessment2. For individual (mainly biological) assessment criteria the proportion of waterbodies without observation data is much larger; the full scope of monitoring under the WFD is therefore still far from being realised. At the same time, 60% of surface waters did not achieve ‘good’ status in the second river basin management plan and waterbodies in Europe are considered to be at high risk of having poor water quality based on combined microbial, physical and physicochemical indicators3

Reflectarrays for satellite telecommunication antennas

International audienc

Effect of incorporation of remineralizing agents into bleaching gels on the microhardness of bovine enamel in situ

This study evaluated the effect of adding calcium or fluoride to 35% hydrogen peroxide (HP) bleaching gel and the effect of human saliva on the microhardness of sound and demineralized enamel, using an in situ model. Cylindrical bovine enamel specimens (3 × 2 mm) were divided into two groups (n = 30): sound enamel (SE) and demineralized enamel (DE). Each group was divided into three subgroups, according to the bleaching gel: 35% HP; 35% HP + calcium; 35% HP + fluoride. After bleaching therapy, the specimens were fixed to intraoral devices worn by 10 volunteers for 7 days. Surface enamel microhardness (SMH) was measured before and after bleaching procedures, and after 1 and 7 days of saliva exposure. Data were analyzed by Repeated Measures ANOVA (5%). The variable time resulted in significant differences for SE and DE groups (p = 0.001). For SE, significantly lower SMH was detected for control at post-bleaching period in comparison to the baseline and after 7 days. For DE, the lowest mean values were obtained before bleaching, and the addition of calcium to the peroxide significantly increased enamel SMH. The exposure to human saliva resulted in increased SMH. The addition of potential remineralizing agents into bleaching gels might play an important role in maintaining the microhardness of sound enamel and in inducing remineralization of artificially demineralized enamel right after bleaching, and the remineralizing action of human saliva might minimize the deleterious effects of bleaching gels on enamel. Clinical significance: The incorporation of calcium into HP bleaching gel might be beneficial for the initial phases of the bleaching procedure.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Dermatoscopia do Granuloma Piogénico

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The Mouse Intestinal Bacterial Collection (miBC) provides host-specific insight into cultured diversity and functional potential of the gut microbiota

Intestinal bacteria influence mammalian physiology, but many types of bacteria are still uncharacterized. Moreover, reference strains of mouse gut bacteria are not easily available, although mouse models are extensively used in medical research. These are major limitations for the investigation of intestinal microbiomes and their interactions with diet and host. It is thus important to study in detail the diversity and functions of gut microbiota members, including those colonizing the mouse intestine. To address these issues, we aimed at establishing the Mouse Intestinal Bacterial Collection (miBC), a public repository of bacterial strains and associated genomes from the mouse gut, and studied host-specificity of colonization and sequence-based relevance of the resource. The collection includes several strains representing novel species, genera and even one family. Genomic analyses showed that certain species are specific to the mouse intestine and that a minimal consortium of 18 strains covered 50-75% of the known functional potential of metagenomes. The present work will sustain future research on microbiota-host interactions in health and disease, as it will facilitate targeted colonization and molecular studies. The resource is available at www.dsmz.de/miBC.</p