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1.
Mol Cell Proteomics ; 23(9): 100825, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39111711

RESUMO

Personalized cancer immunotherapies such as therapeutic vaccines and adoptive transfer of T cell receptor-transgenic T cells rely on the presentation of tumor-specific peptides by human leukocyte antigen class I molecules to cytotoxic T cells. Such neoepitopes can for example arise from somatic mutations and their identification is crucial for the rational design of new therapeutic interventions. Liquid chromatography mass spectrometry (LC-MS)-based immunopeptidomics is the only method to directly prove actual peptide presentation and we have developed a parameter optimization workflow to tune targeted assays for maximum detection sensitivity on a per peptide basis, termed optiPRM. Optimization of collision energy using optiPRM allows for the improved detection of low abundant peptides that are very hard to detect using standard parameters. Applying this to immunopeptidomics, we detected a neoepitope in a patient-derived xenograft from as little as 2.5 × 106 cells input. Application of the workflow on small patient tumor samples allowed for the detection of five mutation-derived neoepitopes in three patients. One neoepitope was confirmed to be recognized by patient T cells. In conclusion, optiPRM, a targeted MS workflow reaching ultra-high sensitivity by per peptide parameter optimization, makes the identification of actionable neoepitopes possible from sample sizes usually available in the clinic.


Assuntos
Mutação , Proteômica , Fluxo de Trabalho , Humanos , Cromatografia Líquida , Proteômica/métodos , Espectrometria de Massas/métodos , Epitopos/imunologia , Neoplasias/imunologia , Peptídeos , Animais , Antígenos de Neoplasias/imunologia , Camundongos , Espectrometria de Massa com Cromatografia Líquida
2.
Sci Adv ; 10(5): eadi9091, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38306431

RESUMO

H3K27M, a driver mutation with T and B cell neoepitope characteristics, defines an aggressive subtype of diffuse glioma with poor survival. We functionally dissect the immune response of one patient treated with an H3K27M peptide vaccine who subsequently entered complete remission. The vaccine robustly expanded class II human leukocyte antigen (HLA)-restricted peripheral H3K27M-specific T cells. Using functional assays, we characterized 34 clonally unique H3K27M-reactive T cell receptors and identified critical, conserved motifs in their complementarity-determining region 3 regions. Using detailed HLA mapping, we further demonstrate that diverse HLA-DQ and HLA-DR alleles present immunogenic H3K27M epitopes. Furthermore, we identified and profiled H3K27M-reactive B cell receptors from activated B cells in the cerebrospinal fluid. Our results uncover the breadth of the adaptive immune response against a shared clonal neoantigen across multiple HLA allelotypes and support the use of class II-restricted peptide vaccines to stimulate tumor-specific T and B cells harboring receptors with therapeutic potential.


Assuntos
Glioma , Linfócitos T , Humanos , Antígenos HLA-DR , Vacinação , Glioma/genética , Epitopos
3.
Nat Med ; 29(10): 2586-2592, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37735561

RESUMO

Substitution of lysine 27 to methionine in histone H3 (H3K27M) defines an aggressive subtype of diffuse glioma. Previous studies have shown that a H3K27M-specific long peptide vaccine (H3K27M-vac) induces mutation-specific immune responses that control H3K27M+ tumors in major histocompatibility complex-humanized mice. Here we describe a first-in-human treatment with H3K27M-vac of eight adult patients with progressive H3K27M+ diffuse midline glioma on a compassionate use basis. Five patients received H3K27M-vac combined with anti-PD-1 treatment based on physician's discretion. Repeat vaccinations with H3K27M-vac were safe and induced CD4+ T cell-dominated, mutation-specific immune responses in five of eight patients across multiple human leukocyte antigen types. Median progression-free survival after vaccination was 6.2 months and median overall survival was 12.8 months. One patient with a strong mutation-specific T cell response after H3K27M-vac showed pseudoprogression followed by sustained complete remission for >31 months. Our data demonstrate safety and immunogenicity of H3K27M-vac in patients with progressive H3K27M+ diffuse midline glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Vacinas , Humanos , Adulto , Animais , Camundongos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Histonas/genética , Glioma/genética , Glioma/terapia , Mutação/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-36982116

RESUMO

To prevent the spread of Coronavirus (COVID-19) and protect the health of school staff and students, Austrian education policymakers introduced several hygiene measures that posed new challenges for teachers. The current paper focuses on teachers' perceptions of hygiene measures in schools during the 2021-2022 school year. In Study 1, 1372 Austrian teachers participated in an online survey at the end of 2021. In Study 2, five teachers participated in an in-depth qualitative interview study. The quantitative results show that half the teachers felt a strong burden from the COVID-19 tests, but that the tests worked better when teachers had more teaching experience. Elementary and secondary school teachers, unlike special education teachers, had fewer problems implementing COVID-19 testing. The qualitative results suggest that teachers needed an acclimatization period for previously unfamiliar tasks, such as COVID-19 testing, to become accustomed to this newly implemented measure. Additionally, wearing facemasks was only evaluated positively in the context of self-serving strategies, while the protection of student health was not considered. In summary, the current study calls attention to the particular vulnerability of teachers and provides insights into the reality of schools in times of crisis that could be particularly helpful to education policymakers.


Assuntos
Teste para COVID-19 , COVID-19 , Humanos , Pandemias/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , Instituições Acadêmicas , Professores Escolares , Higiene
5.
Cancer Cell ; 41(2): 235-251.e9, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36638785

RESUMO

Cancer immunotherapy critically depends on fitness of cytotoxic and helper T cell responses. Dysfunctional cytotoxic T cell states in the tumor microenvironment (TME) are a major cause of resistance to immunotherapy. Intratumoral myeloid cells, particularly blood-borne myeloids (bbm), are key drivers of T cell dysfunction in the TME. We show here that major histocompatibility complex class II (MHCII)-restricted antigen presentation on bbm is essential to control the growth of brain tumors. Loss of MHCII on bbm drives dysfunctional intratumoral tumor-reactive CD8+ T cell states through increased chromatin accessibility and expression of Tox, a critical regulator of T cell exhaustion. Mechanistically, MHCII-dependent activation of CD4+ T cells restricts myeloid-derived osteopontin that triggers a chronic activation of NFAT2 in tumor-reactive CD8+ T cells. In summary, we provide evidence that MHCII-restricted antigen presentation on bbm is a key mechanism to directly maintain functional cytotoxic T cell states in brain tumors.


Assuntos
Neoplasias Encefálicas , Linfócitos T Citotóxicos , Humanos , Apresentação de Antígeno , Linfócitos T CD8-Positivos , Antígenos de Histocompatibilidade Classe II/metabolismo , Microambiente Tumoral
6.
Front Immunol ; 14: 1294565, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239352

RESUMO

Peptide-loaded MHC class I (pMHC-I) multimers have revolutionized our capabilities to monitor disease-associated T cell responses with high sensitivity and specificity. To improve the discovery of T cell receptors (TCR) targeting neoantigens of individual tumor patients with recombinant MHC molecules, we developed a peptide-loadable MHC class I platform termed MediMer. MediMers are based on soluble disulfide-stabilized ß2-microglobulin/heavy chain ectodomain single-chain dimers (dsSCD) that can be easily produced in large quantities in eukaryotic cells and tailored to individual patients' HLA allotypes with only little hands-on time. Upon transient expression in CHO-S cells together with ER-targeted BirA biotin ligase, biotinylated dsSCD are purified from the cell supernatant and are ready to use. We show that CHO-produced dsSCD are free of endogenous peptide ligands. Empty dsSCD from more than 30 different HLA-A,B,C allotypes, that were produced and validated so far, can be loaded with synthetic peptides matching the known binding criteria of the respective allotypes, and stored at low temperature without loss of binding activity. We demonstrate the usability of peptide-loaded dsSCD multimers for the detection of human antigen-specific T cells with comparable sensitivities as multimers generated with peptide-tethered ß2m-HLA heavy chain single-chain trimers (SCT) and wild-type peptide-MHC-I complexes prior formed in small-scale refolding reactions. Using allotype-specific, fluorophore-labeled competitor peptides, we present a novel dsSCD-based peptide binding assay capable of interrogating large libraries of in silico predicted neoepitope peptides by flow cytometry in a high-throughput and rapid format. We discovered rare T cell populations with specificity for tumor neoepitopes and epitopes from shared tumor-associated antigens in peripheral blood of a melanoma patient including a so far unreported HLA-C*08:02-restricted NY-ESO-1-specific CD8+ T cell population. Two representative TCR of this T cell population, which could be of potential value for a broader spectrum of patients, were identified by dsSCD-guided single-cell sequencing and were validated by cognate pMHC-I multimer staining and functional responses to autologous peptide-pulsed antigen presenting cells. By deploying the technically accessible dsSCD MHC-I MediMer platform, we hope to significantly improve success rates for the discovery of personalized neoepitope-specific TCR in the future by being able to also cover rare HLA allotypes.


Assuntos
Linfócitos T CD8-Positivos , Peptídeos , Humanos , Receptores de Antígenos de Linfócitos T , Antígenos HLA/metabolismo , Antígenos de Neoplasias
7.
Neurooncol Adv ; 4(1): vdac140, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36196364

RESUMO

Background: Glioblastoma (GBM) is characterized by low numbers of glioma-infiltrating lymphocytes (GIL) with a dysfunctional phenotype. Whether this dysfunctional phenotype is fixed or can be reversed upon ex vivo culturing is poorly understood. The aim of this study was to assess T cell receptor (TCR)-dynamics and -specificities as well as determinants of in vitro GIL expansion by sequencing-based technologies and functional assays to explore the use of GIL for cell therapy. Methods: By means of flow cytometry, T cell functionality in GIL cultures was assessed from 9 GBM patients. TCR beta sequencing (TCRB-seq) was used for TCR repertoire profiling before and after in vitro expansion. Microarrays or RNA sequencing (RNA-seq) were performed from 6 micro-dissected GBM tissues and healthy brain RNA to assess the individual expression of GBM-associated antigens (GAA). GIL reactivity against in silico predicted tumor-associated antigens (TAA) and patient-individual GAA was assessed by ELISpot assay. Combined ex vivo single cell (sc)TCR-/RNA-seq and post-expansion TCRB-seq were used to evaluate transcriptional signatures that determine GIL expansion. Results: Human GIL regains cellular fitness upon in vitro expansion. Profound TCR dynamics were observed during in vitro expansion and only in one of six GIL cultures, reactivity against GAA was observed. Paired ex vivo scTCR/RNA-seq and TCRB-seq revealed predictive transcriptional signatures that determine GIL expansion. Conclusions: Profound TCR repertoire dynamics occur during GIL expansion. Ex vivo transcriptional T cell states determine expansion capacity in gliomas. Our observation has important implications for the use of GIL for cell therapy including genetic manipulation to maintain both antigen specificity and expansion capacity.

8.
Front Psychol ; 13: 917676, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967702

RESUMO

The aim of the study was to illustrate the impact of teachers' implementation of differentiation and individualization (perceived by students) on students' perception of their inclusion regarding their social inclusion, emotional wellbeing and academic self-concept. The study sample comprised 824 third-to-eighth-grade students [255 males (31%) and 569 females (69%)]. Around 10% of the sample (82) had special educational needs (SEN). Students' perceived inclusion levels and academic self-concept were examined with the Arabic version of the Perceptions of Inclusion Questionnaire (PIQ-S-AR). Students' ratings of inclusive practices in their classroom were examined using the Arabic version of the Inclusive Teaching Practices Scale (ITPS). SEN students expressed lower perceived social inclusion, emotional inclusion, and academic self-concept in comparison with non-SEN students. Moreover, high levels of inclusive teaching practices strongly predicted students' perceived emotional inclusion, social inclusion, and academic self-concept. The results of the study supported the importance of school-level inclusive teaching practices and their relation to students' school experiences. It also highlighted the need for schools and teachers to work towards improved school-level inclusion experiences for SEN students.

9.
Neurol Res Pract ; 4(1): 20, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35599302

RESUMO

INTRODUCTION: Isocitrate dehydrogenase (IDH) mutations are disease-defining mutations in IDH-mutant astrocytomas and IDH-mutant and 1p/19q-codeleted oligodendrogliomas. In more than 80% of these tumors, point mutations in IDH type 1 (IDH1) lead to expression of the tumor-specific protein IDH1R132H. IDH1R132H harbors a major histocompatibility complex class II (MHCII)-restricted neoantigen that was safely and successfully targeted in a first-in human clinical phase 1 trial evaluating an IDH1R132H 20-mer peptide vaccine (IDH1-vac) in newly diagnosed astrocytomas concomitant to standard of care (SOC). METHODS: AMPLIFY-NEOVAC is a randomized, 3-arm, window-of-opportunity, multicenter national phase 1 trial to assess safety, tolerability and immunogenicity of IDH1-vac combined with avelumab (AVE), an immune checkpoint inhibitor (ICI) targeting programmed death-ligand 1 (PD-L1). The target population includes patients with resectable IDH1R132H-mutant recurrent astrocytoma or oligodendroglioma after SOC. Neoadjuvant and adjuvant immunotherapy will be administered to 48 evaluable patients. In arm 1, 12 patients will receive IDH1-vac; in arm 2, 12 patients will receive the combination of IDH1-vac and AVE, and in arm 3, 24 patients will receive AVE only. Until disease progression according to immunotherapy response assessment for neuro-oncology (iRANO) criteria, treatment will be administered over a period of maximum 43 weeks (primary treatment phase) followed by facultative maintenance treatment. PERSPECTIVE: IDH1R132H 20-mer peptide is a shared clonal driver mutation-derived neoepitope in diffuse gliomas. IDH1-vac safely targets IDH1R132H in newly diagnosed astrocytomas. AMPLIFY-NEOVAC aims at (1) demonstrating safety of enhanced peripheral IDH1-vac-induced T cell responses by combined therapy with AVE compared to IDH1-vac only and (2) investigating intra-glioma abundance and phenotypes of IDH1-vac induced T cells in exploratory post-treatment tissue analyses. In an exploratory analysis, both will be correlated with clinical outcome. TRIAL REGISTRATION: NCT03893903.

10.
Front Psychol ; 12: 702606, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867585

RESUMO

Starting with the COVID-19 pandemic, research intensively investigated the effects of school lockdowns on involved stakeholders, such as teachers, students and parents. However, as research projects had to be hurriedly conducted, in-depth and longitudinal studies are lacking. Therefore, the current study uses data from a longitudinal study to investigate the well-being of Austrian in-service teachers during the COVID-19 pandemic. In total 256 teachers took part at both measurement waves and participated in an online survey. Standardized questionnaires were used to assess teachers' perception of emotional experiences and job satisfaction before COVID-19 (retrospective, t1), during the first (in situ, t2) and during the second school lockdown (in situ, t3). The results indicated that the vast majority of teachers generally felt a high level of job satisfaction. However, teachers' satisfaction decreased between regular teaching and school lockdowns. Similarly, positive emotional activation was reduced and negative activation increased. Further, results from a positive activation cross-lagged path model indicated that the lack of positive activation led to lower job satisfaction. For negative emotional activation, job satisfaction during the first school lockdown predicted negative activation at the second lockdown.

11.
Front Psychol ; 12: 676482, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566756

RESUMO

Addressing students' individual needs is a crucial component of inclusive teaching. However, empirical evidence comparing practices such as differentiation and grouping strategies within inclusive, regular and special classes is still lacking. The present study contrasts these settings using data from the German National Educational Panel Study (NEPS). Data from 1034 teachers (755 regular, 89 inclusive, 190 special teachers) teaching the subject German in secondary school (grade 5 to grade 8) were used. Results show the highest use of differentiation in special school classes. Teachers' use the majority of grouping practices to a similar extent when comparing the three educational settings. Class size and the number of students with migration background were predictors for teachers' use of differentiation, whereas patterns of grouping strategies were predicted by students' gender and teachers' experience.

12.
EMBO Mol Med ; 13(8): e13953, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34254741

RESUMO

IgG4-related disease (IgG4-RD) is a fibroinflammatory disorder signified by aberrant infiltration of IgG4-restricted plasma cells into a variety of organs. Clinical presentation is heterogeneous, and pathophysiological mechanisms of IgG4-RD remain elusive. There are very few cases of IgG4-RD with isolated central nervous system manifestation. By leveraging single-cell sequencing of the cerebrospinal fluid (CSF) of a patient with an inflammatory intracranial pseudotumor, we provide novel insights into the immunopathophysiology of IgG4-RD. Our data illustrate an IgG4-RD-associated polyclonal T-cell response in the CSF and an oligoclonal T-cell response in the parenchymal lesions, the latter being the result of a multifaceted cell-cell interaction between immune cell subsets and pathogenic B cells. We demonstrate that CD8+ T effector memory cells might drive and sustain autoimmunity via macrophage migration inhibitory factor (MIF)-CD74 signaling to immature B cells and CC-chemokine ligand 5 (CCL5)-mediated recruitment of cytotoxic CD4+ T cells. These findings highlight the central role of T cells in sustaining IgG4-RD and open novel avenues for targeted therapies.


Assuntos
Doença Relacionada a Imunoglobulina G4 , Linfócitos B , Encéfalo , Linfócitos T CD8-Positivos , Humanos , Memória Imunológica
13.
Clin Cancer Res ; 26(16): 4289-4301, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32303540

RESUMO

PURPOSE: During our efforts to develop tumor-infiltrating lymphocyte (TIL) therapy to counter the devastating recurrence rate in patients with primary resectable pancreatic ductal adenocarcinoma (PDA), we found that PDA TILs can readily be expanded in vitro and that the majority of resulting TIL cultures show reactivity against the autologous tumor. However, the fraction of tumor-reactive T cells is low. We investigated to which extent this was related to the in vitro expansion. EXPERIMENTAL DESIGN: We compared the clonal composition of TIL preparations before and after in vitro expansion using T-cell receptor (TCR) deep sequencing. Our findings for PDA were benchmarked to experiments with melanoma TILs. RESULTS: We found that the TIL TCR repertoire changes dramatically during in vitro expansion, leading to loss of tumor- dominant T-cell clones and overgrowth by newly emerging T-cell clones that are barely detectable in the tumor. These changes are primarily driven by differences in the intrinsic in vitro expansion capacity of T-cell clones. Single-cell experiments showed an association between poor proliferative capacity and expression of markers related to antigen experience and dysfunction. Furthermore, we found that spatial heterogeneity of the TIL repertoire resulted in TCR repertoires that are greatly divergent between TIL cultures derived from distant tumor samples of the same patient. CONCLUSIONS: Culture-induced changes in clonal composition are likely to affect tumor reactivity of TIL preparations. TCR deep sequencing provides important insights into the factors that govern the outcome of in vitro TIL expansion and thereby a path toward optimization of the production of TIL preparations with high therapeutic efficacy.See related commentary by Lozano-Rabella and Gros, p. 4177.


Assuntos
Linfócitos do Interstício Tumoral , Linfócitos T , Células Clonais , Humanos , Recidiva Local de Neoplasia , Receptores de Antígenos de Linfócitos T/genética
14.
Int J Med Microbiol ; 308(7): 969-976, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30064820

RESUMO

Escherichia coli-induced hemolytic uremic syndrome (eHUS) is a life-threatening complication of infection with Shiga toxin (Stx), in particular Stx2a-producing Escherichia coli. Enhanced coagulation activation with formation of microthrombi seems to be a key event in development of eHUS. Platelet activation has been postulated as a possible, but controversially debated mechanism. The present study investigated the effect of Stx2a on plasmatic coagulation and platelets. Binding studies were initially performed with ELISA and co-immunoprecipitation and supported by quartz crystal microbalance with dissipation monitoring (QCM-D). Antithrombin (AT) activity was measured using the automated BCS XP® system. ROTEM® was used for functional coagulation testing. Platelet binding and activation was studied with FACS and light-transmission aggregometry. We found binding of Stx2a to AT, an important inhibitor of blood coagulation, but only a mild albeit significant reduction of AT activity against FXa in the presence of Stx2a. QCM-D analysis also showed binding of Stx2a to heparin and an impaired binding of AT to Stx2a-bound heparin. ROTEM® using Stx2a-treated platelet-poor plasma revealed a significant, but only moderate shortening of clotting time. Neither binding nor activation of platelets by Stx2a could be demonstrated. In summary, data of this study suggest that Stx2a binds to AT, but does not induce major effects on plasmatic coagulation. In addition, no interaction with platelets occurred. The well-known non-beneficial administration of heparin in eHUS patients could be explained by the interaction of Stx2a with heparin.


Assuntos
Antitrombinas/metabolismo , Coagulação Sanguínea/fisiologia , Heparina/metabolismo , Agregação Plaquetária/imunologia , Toxina Shiga II/metabolismo , Plaquetas/imunologia , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Ligação Proteica/fisiologia , Escherichia coli Shiga Toxigênica/patogenicidade
15.
Pediatrics ; 118(2): 563-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16882808

RESUMO

OBJECTIVE: The purpose of this work was to record the current practice of restricting ongoing intensive care in severely ill newborns. METHODS: This was a prospective observational study over a 30-month period of consecutive newborns for whom restriction of ongoing intensive care was taken into consideration, discussed, or decided on. A standardized form recorded patients' medical condition, the type of restriction decided on, parents' wishes, and their information level. The research was conducted in a neonatal unit of a level III university children's hospital, with no interventions. RESULTS: Forty patients were enrolled, 25 were preterm, 21 had either a genetic defect or an inborn malformation. Restriction of ongoing intensive care was decided on for 32 patients with a great variety of specified recommendations. Thirty-six patients died during the observation period. In general, parents were well informed; however, their wishes concerning restriction of ongoing intensive care were unknown in approximately 25% of cases. CONCLUSIONS: The decision-making process for restriction of ongoing intensive care is well established, but the role of parents needs to be defined.


Assuntos
Hemorragia Cerebral/terapia , Anormalidades Congênitas/terapia , Doenças Genéticas Inatas/terapia , Terapia Intensiva Neonatal , Recusa em Tratar , Hemorragia Cerebral/epidemiologia , Anormalidades Congênitas/epidemiologia , Tomada de Decisões , Comitês de Ética Clínica , Doenças Genéticas Inatas/epidemiologia , Alemanha/epidemiologia , Idade Gestacional , Mortalidade Hospitalar , Hospitais Universitários/estatística & dados numéricos , Humanos , Recém-Nascido , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/terapia , Terapia Intensiva Neonatal/ética , Terapia Intensiva Neonatal/estatística & dados numéricos , Futilidade Médica , Pais/psicologia , Alta do Paciente , Médicos/psicologia , Prognóstico , Estudos Prospectivos , Qualidade de Vida , Recusa em Tratar/ética , Recusa em Tratar/estatística & dados numéricos
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