13 results on '"Herster F"'
Search Results
2. Impact of TLR, IL-1R and TACI receptor signaling in a MyD88 L265P mutation-driven murine model of diffuse large B cell lymphoma
- Author
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Wolz, O. O., Kittel, G., Cardona, Y., Herster, F., Kashkar, H., Reinhardt, H. C., Weber, A. N. R., Wolz, O. O., Kittel, G., Cardona, Y., Herster, F., Kashkar, H., Reinhardt, H. C., and Weber, A. N. R.
- Published
- 2017
3. Multicenter Real-World Analysis of Combined MET and EGFR Inhibition in Patients With Non-Small Cell Lung Cancer and Acquired MET Amplification or Polysomy After EGFR Inhibition.
- Author
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Acker F, Klein A, Rasokat A, Eisert A, Kron A, Christopoulos P, Stenzinger A, Kulhavy J, Hummel HD, Waller CF, Hummel A, Rittmeyer A, Kropf-Sanchen C, Zimmermann H, Lörsch A, Kauffmann-Guerrero D, Schütz M, Herster F, Thielert F, Demes M, Althoff FC, Aguinarte L, Heinzen S, Rost M, Schulte H, Stratmann J, Rohde G, Büttner R, Wolf J, Sebastian M, and Michels S
- Subjects
- Humans, Male, Female, Middle Aged, Aged, Adult, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Aged, 80 and over, Mutation, Carcinoma, Non-Small-Cell Lung drug therapy, Carcinoma, Non-Small-Cell Lung genetics, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung mortality, Proto-Oncogene Proteins c-met genetics, Proto-Oncogene Proteins c-met antagonists & inhibitors, Lung Neoplasms drug therapy, Lung Neoplasms genetics, Lung Neoplasms pathology, Lung Neoplasms mortality, ErbB Receptors genetics, ErbB Receptors antagonists & inhibitors, Gene Amplification, Protein Kinase Inhibitors therapeutic use
- Abstract
Purpose: MET amplification is a common resistance mechanism to EGFR inhibition in EGFR-mutant non-small cell lung cancer (NSCLC). Several trials showed encouraging results with combined EGFR and MET inhibition (EGFRi/METi). However, MET amplification has been inconsistently defined and frequently included both polysomy and true amplification., Methods: This is a multicenter, real-world analysis in patients with disease progression on EGFR inhibition and MET copy number gain (CNG), defined as either true amplification (MET to centromere of chromosome 7 ratio [MET-CEP7] ≥ 2) or polysomy (gene copy number ≥ 5, MET-CEP7 < 2)., Results: A total of 43 patients with MET CNG were included, 42 of whom were detected by FISH. Twenty-three, 7, and 14 received EGFRi/METi, METi, and SoC, respectively. Patients in the EGFRi/METi cohort exhibited a superior real-world clinical benefit rate, defined as stable disease or better, of 82% (95% confidence interval [CI], 60-95) compared to METi (29%, 4-71) and SoC (50%, 23-77). Median real-world progression-free survival was longer with EGFRi/METi with 9.8 vs. 4.3 months with METi (hazard ratio [HR], 0.19, 95% CI, 0.06-0.57) and 3.7 months with SoC (0.41, 0.18-0.91), respectively. Overall survival was numerically improved. Interaction analysis with treatment and type of CNG (amplification vs. polysomy) suggests that differences were exclusively driven by MET-amplified patients receiving EGFRi/METi (HR for OS, 0.09, 0.01-0.54)., Conclusion: In this real-world study, EGFRi/METi showed clinical benefit over METi and SoC. Future studies should focus on the differential impact of the type of MET CNG with a focus on true MET amplification as predictor of response., Competing Interests: Disclosure F. A. received support for attending meetings and speaker's honoraria from AstraZeneca, and consultant fees from IQVIA. P. C. received research funding from AstraZeneca, Amgen, Boehringer Ingelheim, Merck, Novartis, Roche, and Takeda, speaker's honoraria from AstraZeneca, Gilead, Janssen, Novartis, Roche, Pfizer, Thermo Fisher, and Takeda, support for attending meetings from AstraZeneca, Eli Lilly, Daiichi Sankyo, Janssen, Gilead, Novartis, Pfizer, Takeda, and personal fees for participating to advisory boards from AstraZeneca, Boehringer Ingelheim, Chugai, Pfizer, Novartis, MSD, Takeda and Roche, all outside the submitted work. H.-D. H. received personal fees for participating to advisory boards from Amgen, speaker's honoraria from Amgen, Boehringer Ingelheim, and Bristol-Myers Squibb. C. F. W. received personal fees for participating to advisory boards from Amgen, AstraZeneca, Boehringer Ingelheim, Bristol-Myers Squibb, Chugai, Lilly, Merck, MSD, Novartis, Pfizer, Roche, and Takeda, consultancy fees from Mylan/Viatris, Alvotech, Roche, support for attending meetings from Amgen, Bristol-Myers Squibb, Janssen, Lilly. A. Ri. received speaker's honoraria and consulting fees from Abbvie, AstraZeneca, Bristol-Myers Squibb, Boehringer Ingelheim, Daiichi Sankyo, Lilly, GSK, MSD, Novartis, Pfizer, Roche/Genentech. H. Z. received support for attending meetings from Janssen, speaker's honoraria from Pierre Fabre, and Roche. A. L. received support for attending meetings from Abbvie. D. K.-G. received consultant fees from AstraZeneca, Boehringer Ingelheim, Roche, MSD, Pfizer, Bristol-Myers Squibb, GSK, Novartis, Takeda, Sanofi, and Janssen, support for attending meetings from Takeda, Boehringer-Ingelheim, Janssen. R. B. received honoraries for lectures and advisory boards for AbbVie, Amgen, AstraZeneca, Bayer, Bristol-Myers Squibb, Boehringer Ingelheim, Illumina, Janssen, Lilly, Merck-Serono, MSD, Novartis, Qiagen, Pfizer, Roche, Targos MP Inc. R.B. is a Co-Founder and Co-Owner of Targos Inc / Kassel (previous); Gnothis Inc / Stockholm (current); Timer Therapeutics Inc / Fulda & Freiburg (current). M. D. received personal fees for participating in advisory boards from AstraZeneca, Bayer, Diaceutics, Biocartis, Sophia Genetics, and ThermoFisher. F. C. A. has received research grants from Novartis, support for attending meetings and/or travel from Amgen, and consultant fees from IQVIA. S. H. has received research grants from Novartis and travel support from BeiGene. J. A. S. received personal fees from Boehringer Ingelheim, AstraZeneca, Roche, Bristol-Myers Squibb, Amgen, LEO pharma, Novartis, and Takeda. J. W. received speaker's honoraria and personal fees for participating in advisory boards from Amgen, AstraZeneca, Bayer, Blueprint, Bristol-Myers Squibb, Boehringer Ingelheim, Chugai, Daiichi Sankyo, Ignyta, Janssen, Lilly, Loxo, Merck, Mirati, MSD, Novartis, Nuvalent, Pfizer, Roche, Seattle Genetics, Takeda, and Turning Point and received institutional research grants from Bristol-Myers Squibb, Janssen, Novartis, Pfizer, and AstraZeneca. M. S. received research grants from AstraZeneca, consulting fees from AstraZeneca, Bristol-Myers Squibb, MSD, Novartis, Lilly, Roche, Boehringer Ingelheim, Amgen, Takeda, Johnson, Merck-Serono, and GSK, and speaker's honoraria from AstraZeneca, Bristol-Myers Squibb, MSD, Novartis, Lilly, Roche, Boehringer Ingelheim, Amgen, Takeda, Johnson, CureVac, BioNTech, Merck-Serono, GSK, Daiichi, and Pfizer. S. M. has received research grants from Novartis and Pfizer, personal fees from Eli Lilly, Janssen, and Astra Zeneca as well as support for attending meetings and/or travel from Eli Lilly, and Janssen. A. S. has received speaker's honoraria from Agilent, Aignostics, Amgen, Astellas, Astra Zeneca, Bayer, BMS, Eli Lilly, Illumina, Incyte, Janssen, MSD, Novartis, Pfizer, Qlucore, Roche, Seagen, Servier, Takeda, and Thermo Fisher, and institutional research grants from Bayer, BMS, Chugai, and Incyte. All other authors declared no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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4. Activity of afatinib in patients with NSCLC harboring novel uncommon EGFR mutations with or without co-mutations: a case report.
- Author
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Christopoulos P, Herster F, Hoffknecht P, Falk M, Tiemann M, Kopp HG, Althoff A, Stammberger A, and Laack E
- Abstract
Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) represent first-line standard of care in unresectable EGFR mutation-positive ( EGFR m+) non-small cell lung cancer (NSCLC). However, 10-20% of patients with EGFR m+ NSCLC have uncommon EGFR variants, defined as mutations other than L858R substitutions or exon 19 deletions. NSCLC harboring uncommon EGFR mutations may demonstrate lower sensitivity to targeted agents than NSCLC with L858R or exon 19 deletion mutations. Prospective clinical trial data in patients with NSCLC uncommon EGFR mutations are lacking. Afatinib is a second-generation TKI and the only Food and Drug Administration-approved drug for some of the more prevalent uncommon EGFR mutations. We present a series of seven case reports describing clinical outcomes in afatinib-treated patients with NSCLC harboring a diverse range of extremely rare mutations with or without co-mutations affecting other genes. EGFR alterations included compound mutations, P-loop αC-helix compressing mutations, and novel substitution mutations. We also present a case with NSCLC harboring a novel EGFR :: CCDC6 gene fusion. Overall, the patients responded well to afatinib, including radiologic partial responses in six patients during treatment. Responses were durable for three patients. The cases presented are in line with a growing body of clinical and preclinical evidence that indicating that NSCLC with various uncommon EGFR mutations, with or without co-mutations, may be sensitive to afatinib., Competing Interests: AS is a current employee of Boehringer Ingelheim. PC reports research funding from Amgen, AstraZeneca, Boehringer Ingelheim, Novartis, Roche, Takeda, and advisory board/lecture fees from AstraZeneca, Boehringer Ingelheim, Chugai, Daiichi Sankyo, Gilead, Janssen, Novartis, Pfizer, Roche, Takeda, and Thermo Fisher. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Christopoulos, Herster, Hoffknecht, Falk, Tiemann, Kopp, Althoff, Stammberger and Laack.)
- Published
- 2024
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5. Germline findings in patients with advanced malignancies screened with paired blood-tumour testing for personalised treatment approaches.
- Author
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Roggia C, Armeanu-Ebinger S, Gschwind A, Seibel-Kelemen O, Hertler S, Faust U, Liebmann A, Haack TB, Neumann M, Bonzheim I, Forschner A, Kopp HG, Herster F, Hartkopf A, Bitzer M, Malek NP, Brecht IB, Ruhm K, Möller Y, Löwenheim H, Ossowski S, Rieß OH, and Schroeder C
- Subjects
- Humans, Precision Medicine, Germ-Line Mutation, Mutation, Genes, BRCA2, Genetic Predisposition to Disease, Genetic Testing methods, Neoplasms diagnosis, Neoplasms genetics, Neoplasms therapy, Hematologic Neoplasms
- Abstract
Background: Sequencing of tumour tissue with comprehensive gene panels is increasingly used to guide treatment in precision oncology. Analysis of tumour-normal pairs allows in contrast to tumour-only assessment direct discrimination between somatic and germline alterations, which might have important implications not only for the patients but also their families., Methods: We performed tumour normal sequencing with a large gene panel in 1048 patients with advanced cancer to support treatment decision. Sequencing results were correlated with clinical and family data., Results: We identified 156 likely pathogenic or pathogenic (LP/P) germline variants in cancer predisposition genes (CPGs) in 144 cases (13.7%). Of all patients, 8.8% had a LP/P variant in autosomal-dominant cancer predisposition genes (AD-CPGs), most of them being genes with high or moderate penetrance (ATM, BRCA2, CHEK2 and BRCA1). In 48 cases, the P/LP variant matched the expected tumour spectrum. A second variant in tumour tissue was found in 31 patients with AD-CPG variants. Low frequency mutations in either TP53, ATM or DNMT3A in the normal sample indicated clonal haematopoiesis in five cases., Conclusions: Tumour-normal testing for personalised treatment identifies germline LP/P variants in a relevant proportion of patients with cancer. The majority of them would not have been referred to genetic counselling based on family history. Indirect functional readouts of tumour-normal sequencing can provide novel links between CPGs and unexpected cancers. The interpretation of increasingly complex datasets in precision oncology is challenging and concepts of interdisciplinary personalised cancer prevention are needed to support patients and their families., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2023
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6. Prolonged Exposure to Oxaliplatin during HIPEC Improves Effectiveness in a Preclinical Micrometastasis Model.
- Author
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Seyfried N, Yurttas C, Burkard M, Oswald B, Tolios A, Herster F, Kauer J, Jäger T, Königsrainer I, Thiel K, Quante M, Rammensee HG, Venturelli S, Schwab M, Königsrainer A, Beckert S, and Löffler MW
- Abstract
Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) was considered a promising treatment for patients with peritoneal metastasis from colorectal cancer. However, the recently published randomized controlled PRODIGE 7 trial failed to demonstrate survival benefits through the addition of short-term oxaliplatin-based HIPEC. Constituting a complex multifactorial treatment, we investigated HIPEC in a preclinical model concerning the elimination of minimal tumor residues, thereby aiming to better understand the size of effects and respective clinical trial results. Patient samples of peritoneal perfusates obtained during HIPEC treatments and oxaliplatin-containing solutions at clinically relevant dosages, conforming with established HIPEC protocols, were assessed regarding their ability to eliminate modelled ~100 µm thickness cancer cell layers. Impedance-based real-time cell analysis and classical end-point assays were used. Flow cytometry was employed to determine the effect of different HIPEC drug solvents on tumor cell properties. Effectiveness of peritoneal perfusate patient samples and defined oxaliplatin-containing solutions proved limited but reproducible. HIPEC simulations for 30 min reduced the normalized cell index below 50% with peritoneal perfusates from merely 3 out of 9 patients within 72 h, indicating full-thickness cytotoxic effects. Instead, prolonging HIPEC to 1 h enhanced these effects and comprised 7 patients' samples, while continuous drug exposure invariably resulted in complete cell death. Further, frequently used drug diluents caused approximately 25% cell size reduction within 30 min. Prolonging oxaliplatin exposure improved effectiveness of HIPEC to eliminate micrometastases in our preclinical model. Accordingly, insufficient penetration depth, short exposure time, and the physicochemical impact of drug solvents may constitute critical factors.
- Published
- 2022
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7. BTK operates a phospho-tyrosine switch to regulate NLRP3 inflammasome activity.
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Bittner ZA, Liu X, Mateo Tortola M, Tapia-Abellán A, Shankar S, Andreeva L, Mangan M, Spalinger M, Kalbacher H, Düwell P, Lovotti M, Bosch K, Dickhöfer S, Marcu A, Stevanović S, Herster F, Cardona Gloria Y, Chang TH, Bork F, Greve CL, Löffler MW, Wolz OO, Schilling NA, Kümmerle-Deschner JB, Wagner S, Delor A, Grimbacher B, Hantschel O, Scharl M, Wu H, Latz E, and Weber ANR
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- Animals, Inflammation metabolism, Interleukin-1beta metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Agammaglobulinaemia Tyrosine Kinase metabolism, Inflammasomes metabolism, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Tyrosine metabolism
- Abstract
Activity of the NLRP3 inflammasome, a critical mediator of inflammation, is controlled by accessory proteins, posttranslational modifications, cellular localization, and oligomerization. How these factors relate is unclear. We show that a well-established drug target, Bruton's tyrosine kinase (BTK), affects several levels of NLRP3 regulation. BTK directly interacts with NLRP3 in immune cells and phosphorylates four conserved tyrosine residues upon inflammasome activation, in vitro and in vivo. Furthermore, BTK promotes NLRP3 relocalization, oligomerization, ASC polymerization, and full inflammasome assembly, probably by charge neutralization, upon modification of a polybasic linker known to direct NLRP3 Golgi association and inflammasome nucleation. As NLRP3 tyrosine modification by BTK also positively regulates IL-1β release, we propose BTK as a multifunctional positive regulator of NLRP3 regulation and BTK phosphorylation of NLRP3 as a novel and therapeutically tractable step in the control of inflammation., Competing Interests: Disclosures: J.B. Kümmerle-Deschner reported grants from Novartis, personal fees from Novartis, grants from SOBI, and personal fees from SOBI outside the submitted work. B. Grimbacher reported grants from BMBF, grants from DFG, grants from several pharmaceutical companies, personal fees from several pharmaceutical companies, and grants from foundations outside the submitted work. E. Latz is co-founder and consultant to IFM Therapeutics. No other disclosures were reported., (© 2021 Bittner et al.)
- Published
- 2021
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8. Platelets: Underestimated Regulators of Autoinflammation in Psoriasis.
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Herster F, Karbach S, Chatterjee M, and Weber ANR
- Subjects
- Animals, Blood Coagulation immunology, Cardiovascular Diseases blood, Cardiovascular Diseases epidemiology, Cell Communication immunology, Comorbidity, Dermatitis blood, Dermatitis epidemiology, Dermatitis pathology, Disease Models, Animal, Humans, Neutrophils immunology, Psoriasis blood, Psoriasis epidemiology, Psoriasis pathology, Skin immunology, Blood Platelets immunology, Cardiovascular Diseases immunology, Dermatitis immunology, Psoriasis immunology, Skin pathology
- Abstract
Platelets have long been known as mediators of hemostasis and, more recently, as mediators of thromboinflammation, although their physiopathological role has mostly been investigated in the context of disease of internal organs, such as liver and kidney, or systemic disorders. Of late, exciting recent data suggest that platelets may also play a role in inflammation at distal sites such as the skin: recent studies show that platelets, by engaging polymorphonuclear neutrophils (PMNs), contribute to local inflammation in the frequent skin disorder, psoriasis. In an experimental model, systemic depletion of platelets drastically attenuated skin inflammation by preventing PMN infiltration of the skin. A broader role of platelets in different types of skin inflammation is therefore likely, and in this paper, we specifically review recent advances in psoriasis. Special emphasis is given to the crosstalk with systemic platelet effects, which may be of interest in psoriasis-related cardiovascular comorbidities. Furthermore, we discuss the potential for platelet-centered interventions in the therapy for psoriasis., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2021
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9. Staphylococcus aureus Skin Colonization Is Enhanced by the Interaction of Neutrophil Extracellular Traps with Keratinocytes.
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Bitschar K, Staudenmaier L, Klink L, Focken J, Sauer B, Fehrenbacher B, Herster F, Bittner Z, Bleul L, Schaller M, Wolz C, Weber ANR, Peschel A, and Schittek B
- Subjects
- Animals, Cell Communication, Cells, Cultured, Coculture Techniques, Dermatitis, Atopic microbiology, Female, Humans, Male, Mice, Microbiota, Skin microbiology, Staphylococcal Infections microbiology, Surgical Tape, Dermatitis, Atopic immunology, Extracellular Traps metabolism, Keratinocytes immunology, Neutrophils immunology, Skin immunology, Staphylococcal Infections immunology, Staphylococcus aureus physiology
- Abstract
Staphylococcus aureus is a facultative pathogen found on skin and nasal surfaces. It is usually absent from the skin of healthy humans but frequently colonizes the skin of patients with atopic dermatitis. Here, we investigate the functional role of neutrophils in the initial steps of S. aureus skin colonization and how skin commensals modulate the S. aureus-induced recruitment of neutrophils to the skin. Using an epicutaneous mouse skin colonization model, we show that skin inflammation induced by tape-stripping leads to a rapid recruitment of neutrophils, which correlates with enhanced S. aureus skin colonization. Interestingly, the depletion of neutrophils in vivo reduces S. aureus colonization, and in vitro coculture of primary human keratinocytes with neutrophils promotes S. aureus adherence. We demonstrate that the interaction of neutrophil extracellular traps with keratinocytes are responsible for the increased S. aureus skin colonization. Finally, we show that S. epidermidis as part of the skin microbiota can reduce the neutrophil recruitment induced by S. aureus infection. These data suggest that microbiota-mediated skin protection against S. aureus is dampened in an inflammatory environment in which neutrophil extracellular traps released by infiltrating neutrophils unexpectedly contribute to enhanced S. aureus skin colonization., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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10. Neutrophil extracellular trap-associated RNA and LL37 enable self-amplifying inflammation in psoriasis.
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Herster F, Bittner Z, Archer NK, Dickhöfer S, Eisel D, Eigenbrod T, Knorpp T, Schneiderhan-Marra N, Löffler MW, Kalbacher H, Vierbuchen T, Heine H, Miller LS, Hartl D, Freund L, Schäkel K, Heister M, Ghoreschi K, and Weber ANR
- Subjects
- Adult, Animals, Antimicrobial Cationic Peptides, Cytokines genetics, Cytokines immunology, Extracellular Traps genetics, Female, Humans, Male, Mice, Mice, Inbred C57BL, Middle Aged, Neutrophil Infiltration, Psoriasis genetics, RNA genetics, RNA immunology, Toll-Like Receptor 8 genetics, Toll-Like Receptor 8 immunology, Young Adult, Cathelicidins, Extracellular Traps immunology, Neutrophils immunology, Psoriasis immunology
- Abstract
Psoriasis is an inflammatory skin disease with strong neutrophil (PMN) infiltration and high levels of the antimicrobial peptide, LL37. LL37 in complex with DNA and RNA is thought to initiate disease exacerbation via plasmacytoid dendritic cells. However, the source of nucleic acids supposed to start this initial inflammatory event remains unknown. We show here that primary murine and human PMNs mount a fulminant and self-propagating neutrophil extracellular trap (NET) and cytokine response, but independently of the canonical NET component, DNA. Unexpectedly, RNA, which is abundant in NETs and psoriatic but not healthy skin, in complex with LL37 triggered TLR8/TLR13-mediated cytokine and NET release by PMNs in vitro and in vivo. Transfer of NETs to naive human PMNs prompts additional NET release, promoting further inflammation. Our study thus uncovers a self-propagating vicious cycle contributing to chronic inflammation in psoriasis, and NET-associated RNA (naRNA) as a physiologically relevant NET component.
- Published
- 2020
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11. Platelets Aggregate With Neutrophils and Promote Skin Pathology in Psoriasis.
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Herster F, Bittner Z, Codrea MC, Archer NK, Heister M, Löffler MW, Heumos S, Wegner J, Businger R, Schindler M, Stegner D, Schäkel K, Grabbe S, Ghoreschi K, Miller LS, and Weber ANR
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- Adult, Animals, Humans, Imiquimod toxicity, Mice, Mice, Inbred C57BL, Platelet Activation immunology, Platelet Count, Psoriasis pathology, Blood Platelets immunology, Neutrophils immunology, Platelet Aggregation immunology, Psoriasis immunology, Skin pathology
- Abstract
Psoriasis is a frequent systemic inflammatory autoimmune disease characterized primarily by skin lesions with massive infiltration of leukocytes, but frequently also presents with cardiovascular comorbidities. Especially polymorphonuclear neutrophils (PMNs) abundantly infiltrate psoriatic skin but the cues that prompt PMNs to home to the skin are not well-defined. To identify PMN surface receptors that may explain PMN skin homing in psoriasis patients, we screened 332 surface antigens on primary human blood PMNs from healthy donors and psoriasis patients. We identified platelet surface antigens as a defining feature of psoriasis PMNs, due to a significantly increased aggregation of neutrophils and platelets in the blood of psoriasis patients. Similarly, in the imiquimod-induced experimental in vivo mouse model of psoriasis, disease induction promoted PMN-platelet aggregate formation. In psoriasis patients, disease incidence directly correlated with blood platelet counts and platelets were detected in direct contact with PMNs in psoriatic but not healthy skin. Importantly, depletion of circulating platelets in mice in vivo ameliorated disease severity significantly, indicating that both PMNs and platelets may be relevant for psoriasis pathology and disease severity.
- Published
- 2019
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12. Crucial Role of Nucleic Acid Sensing via Endosomal Toll-Like Receptors for the Defense of Streptococcus pyogenes in vitro and in vivo .
- Author
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Hafner A, Kolbe U, Freund I, Castiglia V, Kovarik P, Poth T, Herster F, Weigand MA, Weber ANR, Dalpke AH, and Eigenbrod T
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- Biomarkers, Cytokines metabolism, Humans, Immunity, Cellular, Immunity, Innate, Nitric Oxide metabolism, Nucleic Acids immunology, RNA, Bacterial immunology, Reactive Oxygen Species metabolism, Streptococcal Infections microbiology, Endosomes metabolism, Host-Pathogen Interactions immunology, Streptococcal Infections immunology, Streptococcal Infections metabolism, Streptococcus pyogenes physiology, Toll-Like Receptors metabolism
- Abstract
Streptococcus pyogenes is a major human pathogen causing a variety of diseases ranging from common pharyngitis to life-threatening soft tissue infections and sepsis. Microbial nucleic acids, especially bacterial RNA, have recently been recognized as a major group of pathogen-associated molecular patterns (PAMPs) involved in the detection of Streptococcus pyogenes via endosomal Toll-like receptors (TLRs) in vitro . However, the individual contribution and cooperation between TLRs as well as cell-type and strain specific differences in dependency on nucleic acid detection during S. pyogenes infection in vitro have not been clarified in detail. Moreover, the role of particularly bacterial RNA for the defense of S. pyogenes infection in vivo remains poorly defined. In this study, we report that in all investigated innate immune cells involved in the resolution of bacterial infections, including murine macrophages, dendritic cells and neutrophils, recognition of S. pyogenes strain ATCC12344 is almost completely dependent on nucleic acid sensing via endosomal TLRs at lower MOIs, whereas at higher MOIs, detection via TLR2 plays an additional, yet redundant role. We further demonstrate that different S. pyogenes strains display a considerable inter-strain variability with respect to their nucleic acid dependent recognition. Moreover, TLR13-dependent recognition of S. pyogenes RNA is largely non-redundant in bone marrow-derived macrophages (BMDMs), but less relevant in neutrophils and bone marrow-derived myeloid dendritic cells (BMDCs) for the induction of an innate immune response in vitro . In vivo , we show that a loss of nucleic acid sensing blunts early recognition of S. pyogenes , leading to a reduced local containment of the bacterial infection with subsequent pronounced systemic inflammation at later time points. Thus, our results argue for a crucial role of nucleic acid sensing via endosomal TLRs in defense of S. pyogenes infection both in vitro and in vivo .
- Published
- 2019
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13. The fungal ligand chitin directly binds TLR2 and triggers inflammation dependent on oligomer size.
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Fuchs K, Cardona Gloria Y, Wolz OO, Herster F, Sharma L, Dillen CA, Täumer C, Dickhöfer S, Bittner Z, Dang TM, Singh A, Haischer D, Schlöffel MA, Koymans KJ, Sanmuganantham T, Krach M, Roger T, Le Roy D, Schilling NA, Frauhammer F, Miller LS, Nürnberger T, LeibundGut-Landmann S, Gust AA, Macek B, Frank M, Gouttefangeas C, Dela Cruz CS, Hartl D, and Weber AN
- Subjects
- Animals, Cell Wall drug effects, Cell Wall metabolism, Chitinases metabolism, Female, Humans, Hydrophobic and Hydrophilic Interactions, Immunologic Factors pharmacology, Ligands, Lymphocytes drug effects, Lymphocytes metabolism, Mice, Inbred C57BL, Mice, Knockout, THP-1 Cells, Toll-Like Receptor 1 agonists, Toll-Like Receptor 1 metabolism, Toll-Like Receptor 2 chemistry, Zymosan metabolism, Chitin chemistry, Chitin metabolism, Fungi metabolism, Inflammation metabolism, Inflammation pathology, Toll-Like Receptor 2 metabolism
- Abstract
Chitin is the second most abundant polysaccharide in nature and linked to fungal infection and asthma. However, bona fide immune receptors directly binding chitin and signaling immune activation and inflammation have not been clearly identified because polymeric crude chitin with unknown purity and molecular composition has been used. By using defined chitin (N-acetyl-glucosamine) oligomers, we here identify six-subunit-long chitin chains as the smallest immunologically active motif and the innate immune receptor Toll-like receptor (TLR2) as a primary fungal chitin sensor on human and murine immune cells. Chitin oligomers directly bind TLR2 with nanomolar affinity, and this fungal TLR2 ligand shows overlapping and distinct signaling outcomes compared to known mycobacterial TLR2 ligands. Unexpectedly, chitin oligomers composed of five or less subunits are inactive, hinting to a size-dependent system of immuno-modulation that appears conserved in plants and humans. Since blocking of the chitin-TLR2 interaction effectively prevents chitin-mediated inflammation in vitro and in vivo , our study highlights the chitin-TLR2 interaction as a potential target for developing novel therapies in chitin-related pathologies and fungal disease., (© 2018 The Authors.)
- Published
- 2018
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