Expression und Ko-lokalisation von IL-23, IL-23-Rezeptoren und IL-17 auf Makrophagen, Dendritischen Zellen und T-Zellen der Lunge sowie deren potenzielle Bedeutung in allergischer Atemwegsentzündung in einem HDM-Mausmodell

Einleitung: Bei Asthma bronchiale handelt es sich um eine variable, reversible Verengung der Atemwege, ausgelöst durch entzündliche Prozesse innerhalb der Lunge. Das proinflammatorische Interleukin 23 (IL-23) und der Interleukin-23-Rezeptor (IL-23R) erhöhen über verschiedene nachgeschaltete Signalkaskaden die Interleukin 17-Konzentration bei allergischer Atemwegserkrankung. Interleukin 17 wiederum induziert die neutrophile In-flammation innerhalb der Lunge. Dieser Mechanismus wird oft in schweren, steroid-resistenten Formen des Asthmas bronchiale beobachtet. Aus diesem Grund erscheint ein besseres Verständnis dieser Interleukin-23-Interleukin-17-Achse für zukünftige Therapiestrategien, wel-che die neutrophile Komponente, bzw. neutrophile Phänotypen der Asthmaerkrankung tar-getieren, von großer Bedeutung. Diese Arbeit befasst sich mit der Expression des Interleukin-23-Rezeptors durch verschiedene Immunzellen innerhalb der Lunge im house-dust-mite-Mausmodell. Methoden: Zur Induktion einer allergischen Atemwegsreaktion wurde weiblichen Mäusen intranasal Haus-staubmilbenextrakt appliziert. Nach sieben Wochen erfolgte die Entnahme beider Lungenflü-gel, sowie des Blutvolumens der einzelnen Versuchstiere. Die Atemwegsinflammation wurde mittels Bestimmung von Gesamt-IgE im Serum, sowie his-topathologischer Analyse des Lungengewebes quantifiziert. Die Konzentration von IL-23 und IL-17 im Lungenhomogenat wurde mittels Sandwich-ELISA bestimmt. Nachfolgend wurde die Dichte von neutrophilen Granulozyten im Lungenparenchym, durch Immunfluoreszenzfärbung mit Antikörpern gegenüber neutrophiler Elastase bestimmt. Zur Identifikation IL-23-produzierender Zellen im Lungengewebe erfolgte eine Immunfluores-zenz durch die Kombination von Antikörpern gegen IL-23, F4/80 und CD11c. Die Identifikation und Quantifizierung von IL-23R-positiven Immunzellen der Lunge erfolgte durch Immunfluo-reszenz. Kombiniert wurde hierbei folgende Antikörper: - IL-23R + CD4 - IL-23R + F4/80 + CD11c - IL-23R + F4/80 + iNOS - IL-23R + F4/80 + RELMα - IL-23R + CD38 + c-Myc Anschließend wurde eine Überprüfung einer möglichen Ko-Lokalisation von IL-23R und IL-17, ebenfalls mittels Immunfluoreszenz durchgeführt. Ergebnisse: HDM-behandelte Versuchstiere zeigten höhere Konzentrationen an Gesamt-IgE und IL-23 im Lungenhomogenat. Ebenfalls konnten bei diesen Tieren eine erhöhte Epitheldicke, eine signi-fikante Becherzell-Hyperplasie, sowie eine höhere Dichte an Neutrophile Elastase- positiven Zellen im Lungenparenchym nachgewiesen werden. Nur ein sehr geringer Anteil von IL-23R-exprimierenden CD3-positiven Zellen konnte bestimmt werden. Im Gegensatz dazu wiesen F4/80-positive Makrophagen und F4/80-CD11c+ Dendriti-sche Zellen eine höherfrequente IL-23R-Positivität auf. Bei HDM-behandelten Tieren wiesen lediglich Makrophagen eine signifikante Hochregulation der IL-23R-Expression auf. Eine IL-23R-Expression wurde bei jeder untersuchten Makrophagen-Subpopulation nachge-wiesen. Wobei Mϕ1 und Hybride zwischen Mϕ1- und Mϕ2- Phänotyp eine Hochregulation von IL-23R aufwiesen. Zusätzlich wurde eine Ko-Lokalisation von IL-23R und IL-17 bei F4/80+ Makrophagen nachgewiesen. Diskussion: Die HDM-Behandlung induzierte eine Atemwegsentzündung, inklusive einer signifikanten Neutrophilie. Die Mechanismen des neutrophilen Influx in das Lungenparenchym sind weiter-hin nicht komplett entschlüsselt. Jedoch besteht seit einigen Jahren die Hypothese, dass eine IL-23/IL-17 Dysregulation eine wesentliche Rolle hierbei spielt. Aufgrund der Tatsache, dass eine höhere Konzentration von IL-23 im Lungenhomogenat und ein höherer Prozentsatz IL-23R-positiver Makrophagen in der HDM-Gruppe nachgewiesen werden konnte, könnte dies eine Bekräftigung dieser These darstellen. Entgegen der Erwartungen zeigte sich keine relevante IL-23R-Hochregulation durch CD3+ T-Zellen und CD11c+ F4/80- Dendritische Zellen. Sodass von einer untergeordneten Rolle die-ser Zellen im Gegensatz zu den F4/80+ Makrophagen ausgegangen werden kann. Die Ko-Lokalisation von IL-23R und IL-17 auf Makrophagen könnte darauf hinweisen, eine Lymphozyten-unabhängige, rein durch Makrophagen ausgelöste, IL-23-abhängige IL-17-Produktion existiert.Introduction: Bronchial Asthma is defined as a variable, reversible constriction of the airways, caused by inflammatory processes within the lung. In allergic airway disease, proinflammatory interleukin 23 and its specific interleukin-23-Re-ceptor increase, through variable mechanisms, the concentration of interleukin 17. Interleukin 17 induces a neutrophilic inflammation of the lung. These mechanisms are often observed in severe, steroid-resistant forms of bronchial asthma. For that reason, understanding these IL-23/IL-17-axis seems to be very important for future therapy-strategies, targeting the neutrophil component of asthma. The underlying project deals with expression of interleukin-23-receptors of the different leukocytes of the lung in HDM-mouse-model. Methods: To induce allergic allergic airway inflammation, female C57B16J-mice received house-dust-mite extract intranasally. After seven weeks the lungs and blood of the animals were harvested. Airway inflammation was quantified by determining the concentrations of total serum-IgE and by histopathologic analysis of lung tissue. The concentration of IL-23 and IL-17 in lung homog-enate was measured using sandwich-ELISA. Afterwards, density of neutrophil granulocytes in lung parenchyma was determined using immunofluorescence-staining with antibodies against neutrophile elastasis. Identification of IL-23 producing cells in lung-tissue was performed by Immunofluorescence-staining using antibodies against IL-23, F4/80 and CD11c. The identification and quantification of IL-23R-positive leukocytes was performed using immunofluorescence as well. The following combinations of antibodies were used: - IL-23R + CD4 - IL-23R + F4/80 + CD11c - IL-23R + F4/80 + iNOS - IL-23R + F4/80 + RELMα - IL-23R + CD38 + c-Myc Subsequent, the co-localisation of IL-23R and IL-17 was tested, also using immunofluores-cence. Results: HDM-treated animals exhibited higher concentration of total IgE in serum and IL-23 in lung homogenate. Additionally, these mice showed an increased epithelial thickness, a significant goblet-cell-hyperplasia and higher density of neutrophil elastasis – positive cells per lung pa-renchyma. Only a small amount of IL-23R-expressing CD3-positive cells could be counted. In contrast, F4/80-positive macrophages and F4/80-CD11c+ dendritic cells exhibited a more frequently IL-23R-positivity. In HDM-treated animals, only macrophages showed an upregulation of IL-23-R-expression. IL-23R expression was observed in every macrophage-subpopulation. Mϕ1 and hybrids be-tween Mϕ1 and Mϕ2-phenotype exhibited an upregulation of IL-23R. Additionally, a co-locali-zation of IL-23R and IL-17 in F4/80+ machrophages was detected. Discussion: HDM-treatment induced allergic airway inflammation, including significant neutrophilia. The mechanisms of neutrophil influx in lung-parenchyma are still not completely understood. Since a few years, there is a thesis, that IL-23/IL-17 dysregulation could play a major role. Because of a higher concentration of IL-23 in lung homogenate and an increased percentage of IL-23R-positive macrophages in HDM-treated mice, this thesis could be supported. Against the expectations, CD3+ T-cells and CD11c+ F4/80- dendritic cells showed no upregu-lation of IL-23R. This could reveal a minor part of these cells, in contrast to F4/80+ macro-phages. Co-localization of IL-23R and IL-17 by macrophages could indicate a lymphocyte-independent, only macrophage derived, IL-23 dependent IL-17 production

Allergic airway inflammation induces upregulation of the expression of IL-23R by macrophages and not in CD3 + T cells and CD11c+F4/80- dendritic cells of the lung

Interleukin 23 and the interleukin 23 receptor (IL-23-IL23R) are described as the major enhancing factors for Interleukin 17 (IL-17) in allergic airway infammation. IL-17 is considered to induce neutrophilic infammation in the lung, which is often observed in severe, steroid-resistant asthma-phenotypes. For that reason, understanding of IL-23 and IL-17 axis is very important for future therapy strategies, targeting neutrophil pathway of bronchial asthma. This study aimed to investigate the distribution and expression of IL-23R under physiological and infammatory conditions. Therefore, a house dust mite (HDM) model of allergic airway infammation was performed by treating mice with HDM intranasally. Immunofuorescence staining with panel of antibodies was performed in lung tissues to examine the macrophage, dendritic cell, and T cell subpopulations. The allergic airway infammation was quantifed by histopathological analysis, ELISA measurements, and airway function. HDM-treated mice exhibited a signifcant allergic airway infammation including higher amounts of NE+ cells in lung parenchyma. We found only a small amount of IL-23R positives, out of total CD3+T cells, and no upregulation in HDMtreated animals. In contrast, the populations of F4/80+ macrophages and CD11c+F4/80− dendritic cells (DCs) with IL-23R expression were found to be higher. But HDM treatment leads to a signifcant increase of IL-23R+ macrophages, only. IL23R was expressed by every examined macrophage subpopulation, whereas only Mϕ1 and hybrids between Mϕ1 and Mϕ2 phenotype and not Mϕ2 were found to upregulate IL-23R. Co-localization of IL-23R and IL-17 was only observed in F4/80+ macrophages, suggesting F4/80+ macrophages express IL-23R along with IL-17 in lung tissue. The study revealed that macrophages involving the IL-23 and IL-17 pathway may provide a potential interesting therapeutic target in neutrophilic bronchial asthma

Synergies between interstellar dust and heliospheric science with an Interstellar Probe

We discuss the synergies between heliospheric and dust science, the open science questions, the technological endeavors and programmatic aspects that are important to maintain or develop in the decade to come. In particular, we illustrate how we can use interstellar dust in the solar system as a tracer for the (dynamic) heliosphere properties, and emphasize the fairly unexplored, but potentially important science question of the role of cosmic dust in heliospheric and astrospheric physics. We show that an Interstellar Probe mission with a dedicated dust suite would bring unprecedented advances to interstellar dust research, and can also contribute-through measuring dust - to heliospheric science. This can, in particular, be done well if we work in synergy with other missions inside the solar system, thereby using multiple vantage points in space to measure the dust as it `rolls' into the heliosphere. Such synergies between missions inside the solar system and far out are crucial for disentangling the spatially and temporally varying dust flow. Finally, we highlight the relevant instrumentation and its suitability for contributing to finding answers to the research questions.Comment: 18 pages, 7 Figures, 5 Tables. Originally submitted as white paper for the National Academies Decadal Survey for Solar and Space Physics 2024-203

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements