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1.
PLoS One ; 19(4): e0298407, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38640190

RESUMEN

INTRODUCTION: Vaccination during pregnancy protects both the mother and the foetus from vaccine-preventable diseases. However, uptake of the recommended vaccines (influenza, pertussis, COVID-19) by pregnant women remains low in Europe and the USA. Understanding the reasons for this is crucial to inform strategies to increase vaccination rates in pregnant women. This qualitative systematic review aimed to identify the barriers and facilitators to vaccination against influenza, pertussis/whooping cough and COVID-19 during pregnancy and identify possible strategies to increase vaccination rates. METHODS: We conducted a comprehensive search of electronic databases, including Medline, PsycINFO, CINAHL, Web of Science, WHO database, Embase and grey literature to identify qualitative studies that explored barriers and facilitators to vaccine uptake among pregnant women (PROSPERO CRD42023399488). The search was limited to studies published between 2012 and 2022 conducted in high-income countries with established vaccination programmes during pregnancy. Studies were thematically analysed and underwent quality assessment using the Joanna Briggs Institute validated critical appraisal tool for qualitative research. RESULTS: Out of 2681 articles screened, 28 studies (n = 1573 participants) were eligible for inclusion. Five overarching themes emerged relating to personal, provider and systemic factors. Barriers to vaccine uptake included concerns about vaccine safety and efficacy, lack of knowledge about vaccines' benefits and necessity, fear of adverse effects on the foetus or mother and low perception of disease severity. Facilitators included recommendations from trusted healthcare providers, easy access to vaccination, clear communication on the benefits and safety of vaccination, and positive social influences from family and friends. Strategies for increasing vaccination uptake included strong and proactive vaccine recommendations by trusted healthcare professionals, provision of vaccines during routine antenatal care, and clear and consistent communication about vaccines addressing pregnant women's concerns. CONCLUSION: This review highlights the need for interventions that address the identified barriers to vaccine uptake among pregnant women. Recommendation from a healthcare provider can play a significant role in promoting vaccine uptake, as can clear risk/benefit communication and convenient access to vaccination. Addressing concerns about vaccine safety and providing accurate information about vaccines is also important.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Tos Ferina , Femenino , Embarazo , Humanos , Gripe Humana/prevención & control , Tos Ferina/prevención & control , Vacunación , COVID-19/prevención & control
2.
Nat Commun ; 15(1): 2790, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38555308

RESUMEN

Analysis of DNA methylation in cell-free DNA reveals clinically relevant biomarkers but requires specialized protocols such as whole-genome bisulfite sequencing. Meanwhile, millions of cell-free DNA samples are being profiled by whole-genome sequencing. Here, we develop FinaleMe, a non-homogeneous Hidden Markov Model, to predict DNA methylation of cell-free DNA and, therefore, tissues-of-origin, directly from plasma whole-genome sequencing. We validate the performance with 80 pairs of deep and shallow-coverage whole-genome sequencing and whole-genome bisulfite sequencing data.


Asunto(s)
Ácidos Nucleicos Libres de Células , Metilación de ADN , Metilación de ADN/genética , Secuenciación Completa del Genoma/métodos , Sulfitos , Ácidos Nucleicos Libres de Células/genética , Análisis de Secuencia de ADN/métodos , Secuenciación de Nucleótidos de Alto Rendimiento
3.
Nat Immunol ; 25(4): 644-658, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38503922

RESUMEN

The organization of immune cells in human tumors is not well understood. Immunogenic tumors harbor spatially localized multicellular 'immunity hubs' defined by expression of the T cell-attracting chemokines CXCL10/CXCL11 and abundant T cells. Here, we examined immunity hubs in human pre-immunotherapy lung cancer specimens and found an association with beneficial response to PD-1 blockade. Critically, we discovered the stem-immunity hub, a subtype of immunity hub strongly associated with favorable PD-1-blockade outcome. This hub is distinct from mature tertiary lymphoid structures and is enriched for stem-like TCF7+PD-1+CD8+ T cells, activated CCR7+LAMP3+ dendritic cells and CCL19+ fibroblasts as well as chemokines that organize these cells. Within the stem-immunity hub, we find preferential interactions between CXCL10+ macrophages and TCF7-CD8+ T cells as well as between mature regulatory dendritic cells and TCF7+CD4+ and regulatory T cells. These results provide a picture of the spatial organization of the human intratumoral immune response and its relevance to patient immunotherapy outcomes.


Asunto(s)
Neoplasias Pulmonares , Humanos , Linfocitos T CD8-positivos , Receptor de Muerte Celular Programada 1 , Quimiocinas/metabolismo , Inmunoterapia/métodos , Microambiente Tumoral
4.
bioRxiv ; 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38260558

RESUMEN

Analysis of DNA methylation in cell-free DNA (cfDNA) reveals clinically relevant biomarkers but requires specialized protocols and sufficient input material that limits its applicability. Millions of cfDNA samples have been profiled by genomic sequencing. To maximize the gene regulation information from the existing dataset, we developed FinaleMe, a non-homogeneous Hidden Markov Model (HMM), to predict DNA methylation of cfDNA and, therefore, tissues-of-origin directly from plasma whole-genome sequencing (WGS). We validated the performance with 80 pairs of deep and shallow-coverage WGS and whole-genome bisulfite sequencing (WGBS) data.

5.
Emerg Med Australas ; 36(2): 252-265, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38044755

RESUMEN

OBJECTIVE: To assess Australian and New Zealand emergency clinicians' attitudes towards the use of artificial intelligence (AI) in emergency medicine. METHODS: We undertook a qualitative interview-based study based on grounded theory. Participants were recruited through ED internal mailing lists, the Australasian College for Emergency Medicine Bulletin, and the research teams' personal networks. Interviews were transcribed, coded and themes presented. RESULTS: Twenty-five interviews were conducted between July 2021 and May 2022. Thematic saturation was achieved after 22 interviews. Most participants were from either Western Australia (52%) or Victoria (16%) and were consultants (96%). More participants reported feeling optimistic (10/25) than neutral (6/25), pessimistic (2/25) or mixed (7/25) towards the use of AI in the ED. A minority expressed scepticism regarding the feasibility or value of implementing AI into the ED. Multiple potential risks and ethical issues were discussed by participants including skill loss from overreliance on AI, algorithmic bias, patient privacy and concerns over liability. Participants also discussed perceived inadequacies in existing information technology systems. Participants felt that AI technologies would be used as decision support tools and not replace the roles of emergency clinicians. Participants were not concerned about the impact of AI on their job security. Most (17/25) participants thought that AI would impact emergency medicine within the next 10 years. CONCLUSIONS: Emergency clinicians interviewed were generally optimistic about the use of AI in emergency medicine, so long as it is used as a decision support tool and they maintain the ability to override its recommendations.


Asunto(s)
Inteligencia Artificial , Medicina de Emergencia , Humanos , Consultores , Teoría Fundamentada , Victoria
6.
J Travel Med ; 30(8)2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-37934788

RESUMEN

BACKGROUND: Pregnant women and their babies face significant risks from three vaccine-preventable diseases: COVID-19, influenza and pertussis. However, despite these vaccines' proven safety and effectiveness, uptake during pregnancy remains low. METHODS: We conducted a systematic review (PROSPERO CRD42023399488; January 2012-December 2022 following PRISMA guidelines) of interventions to increase COVID-19/influenza/pertussis vaccination in pregnancy. We searched nine databases, including grey literature. Two independent investigators extracted data; discrepancies were resolved by consensus. Meta-analyses were conducted using random-effects models to estimate pooled effect sizes. Heterogeneity was assessed using the I2 statistics. RESULTS: From 2681 articles, we identified 39 relevant studies (n = 168 262 participants) across nine countries. Fifteen studies (39%) were randomized controlled trials (RCTs); the remainder were observational cohort, quality-improvement or cross-sectional studies. The quality of 18% (7/39) was strong. Pooled results of interventions to increase influenza vaccine uptake (18 effect estimates from 12 RCTs) showed the interventions were effective but had a small effect (risk ratio = 1.07, 95% CI 1.03, 1.13). However, pooled results of interventions to increase pertussis vaccine uptake (10 effect estimates from six RCTs) showed no clear benefit (risk ratio = 0.98, 95% CI 0.94, 1.03). There were no relevant RCTs for COVID-19. Interventions addressed the 'three Ps': patient-, provider- and policy-level strategies. At the patient level, clear recommendations from healthcare professionals backed by text reminders/written information were strongly associated with increased vaccine uptake, especially tailored face-to-face interventions, which addressed women's concerns, dispelled myths and highlighted benefits. Provider-level interventions included educating healthcare professionals about vaccines' safety and effectiveness and reminders to offer vaccinations routinely. Policy-level interventions included financial incentives, mandatory vaccination data fields in electronic health records and ensuring easy availability of vaccinations. CONCLUSIONS: Interventions had a small effect on increasing influenza vaccination. Training healthcare providers to promote vaccinations during pregnancy is crucial and could be enhanced by utilizing mobile health technologies.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Tos Ferina , Embarazo , Femenino , Humanos , Gripe Humana/prevención & control , Tos Ferina/prevención & control , COVID-19/prevención & control , Vacunación
7.
J Biol Chem ; 299(8): 105014, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37414149

RESUMEN

The target for humoral immunity, SARS-CoV-2 spike glycoprotein, has become the focus of vaccine research and development. Previous work demonstrated that the N-terminal domain (NTD) of SARS-CoV-2 spike binds biliverdin-a product of heme catabolism-causing a strong allosteric effect on the activity of a subset of neutralizing antibodies. Herein, we show that the spike glycoprotein is also able to bind heme (KD = 0.5 ± 0.2 µM). Molecular modeling indicated that the heme group fits well within the same pocket on the SARS-CoV-2 spike NTD. Lined by aromatic and hydrophobic residues (W104, V126, I129, F192, F194, I203, and L226), the pocket provides a suitable environment to stabilize the hydrophobic heme. Mutagenesis of N121 has a substantive effect on heme binding (KD = 3000 ± 220 µM), confirming the pocket as a major heme binding location of the viral glycoprotein. Coupled oxidation experiments in the presence of ascorbate indicated that the SARS-CoV-2 glycoprotein can catalyze the slow conversion of heme to biliverdin. The heme trapping and oxidation activities of the spike may allow the virus to reduce levels of free heme during infection to facilitate evasion of the adaptive and innate immunity.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Anticuerpos Antivirales , Biliverdina , Receptores Virales/metabolismo , Anticuerpos Neutralizantes
8.
Nat Commun ; 14(1): 4400, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37474509

RESUMEN

Deciphering individual cell phenotypes from cell-specific transcriptional processes requires high dimensional single cell RNA sequencing. However, current dimensionality reduction methods aggregate sparse gene information across cells, without directly measuring the relationships that exist between genes. By performing dimensionality reduction with respect to gene co-expression, low-dimensional features can model these gene-specific relationships and leverage shared signal to overcome sparsity. We describe GeneVector, a scalable framework for dimensionality reduction implemented as a vector space model using mutual information between gene expression. Unlike other methods, including principal component analysis and variational autoencoders, GeneVector uses latent space arithmetic in a lower dimensional gene embedding to identify transcriptional programs and classify cell types. In this work, we show in four single cell RNA-seq datasets that GeneVector was able to capture phenotype-specific pathways, perform batch effect correction, interactively annotate cell types, and identify pathway variation with treatment over time.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Análisis de Componente Principal , Secuenciación del Exoma , Análisis de Secuencia de ARN/métodos , Análisis por Conglomerados
9.
bioRxiv ; 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37066412

RESUMEN

The organization of immune cells in human tumors is not well understood. Immunogenic tumors harbor spatially-localized multicellular 'immunity hubs' defined by expression of the T cell-attracting chemokines CXCL10/CXCL11 and abundant T cells. Here, we examined immunity hubs in human pre-immunotherapy lung cancer specimens, and found that they were associated with beneficial responses to PD-1-blockade. Immunity hubs were enriched for many interferon-stimulated genes, T cells in multiple differentiation states, and CXCL9/10/11 + macrophages that preferentially interact with CD8 T cells. Critically, we discovered the stem-immunity hub, a subtype of immunity hub strongly associated with favorable PD-1-blockade outcomes, distinct from mature tertiary lymphoid structures, and enriched for stem-like TCF7+PD-1+ CD8 T cells and activated CCR7 + LAMP3 + dendritic cells, as well as chemokines that organize these cells. These results elucidate the spatial organization of the human intratumoral immune response and its relevance to patient immunotherapy outcomes.

10.
Nat Genet ; 55(5): 807-819, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37024582

RESUMEN

Anti-PD-1/PD-L1 agents have transformed the treatment landscape of advanced non-small cell lung cancer (NSCLC). To expand our understanding of the molecular features underlying response to checkpoint inhibitors in NSCLC, we describe here the first joint analysis of the Stand Up To Cancer-Mark Foundation cohort, a resource of whole exome and/or RNA sequencing from 393 patients with NSCLC treated with anti-PD-(L)1 therapy, along with matched clinical response annotation. We identify a number of associations between molecular features and outcome, including (1) favorable (for example, ATM altered) and unfavorable (for example, TERT amplified) genomic subgroups, (2) a prominent association between expression of inducible components of the immunoproteasome and response and (3) a dedifferentiated tumor-intrinsic subtype with enhanced response to checkpoint blockade. Taken together, results from this cohort demonstrate the complexity of biological determinants underlying immunotherapy outcomes and reinforce the discovery potential of integrative analysis within large, well-curated, cancer-specific cohorts.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Transcriptoma/genética , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/uso terapéutico , Genómica
11.
Lancet Haematol ; 10(3): e203-e212, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36858677

RESUMEN

BACKGROUND: Patients with precursors to multiple myeloma are dichotomised as having monoclonal gammopathy of undetermined significance or smouldering multiple myeloma on the basis of monoclonal protein concentrations or bone marrow plasma cell percentage. Current risk stratifications use laboratory measurements at diagnosis and do not incorporate time-varying biomarkers. Our goal was to develop a monoclonal gammopathy of undetermined significance and smouldering multiple myeloma stratification algorithm that utilised accessible, time-varying biomarkers to model risk of progression to multiple myeloma. METHODS: In this retrospective, multicohort study, we included patients who were 18 years or older with monoclonal gammopathy of undetermined significance or smouldering multiple myeloma. We evaluated several modelling approaches for predicting disease progression to multiple myeloma using a training cohort (with patients at Dana-Farber Cancer Institute, Boston, MA, USA; annotated from Nov, 13, 2019, to April, 13, 2022). We created the PANGEA models, which used data on biomarkers (monoclonal protein concentration, free light chain ratio, age, creatinine concentration, and bone marrow plasma cell percentage) and haemoglobin trajectories from medical records to predict progression from precursor disease to multiple myeloma. The models were validated in two independent validation cohorts from National and Kapodistrian University of Athens (Athens, Greece; from Jan 26, 2020, to Feb 7, 2022; validation cohort 1), University College London (London, UK; from June 9, 2020, to April 10, 2022; validation cohort 1), and Registry of Monoclonal Gammopathies (Czech Republic, Czech Republic; Jan 5, 2004, to March 10, 2022; validation cohort 2). We compared the PANGEA models (with bone marrow [BM] data and without bone marrow [no BM] data) to current criteria (International Myeloma Working Group [IMWG] monoclonal gammopathy of undetermined significance and 20/2/20 smouldering multiple myeloma risk criteria). FINDINGS: We included 6441 patients, 4931 (77%) with monoclonal gammopathy of undetermined significance and 1510 (23%) with smouldering multiple myeloma. 3430 (53%) of 6441 participants were female. The PANGEA model (BM) improved prediction of progression from smouldering multiple myeloma to multiple myeloma compared with the 20/2/20 model, with a C-statistic increase from 0·533 (0·480-0·709) to 0·756 (0·629-0·785) at patient visit 1 to the clinic, 0·613 (0·504-0·704) to 0·720 (0·592-0·775) at visit 2, and 0·637 (0·386-0·841) to 0·756 (0·547-0·830) at visit three in validation cohort 1. The PANGEA model (no BM) improved prediction of smouldering multiple myeloma progression to multiple myeloma compared with the 20/2/20 model with a C-statistic increase from 0·534 (0·501-0·672) to 0·692 (0·614-0·736) at visit 1, 0·573 (0·518-0·647) to 0·693 (0·605-0·734) at visit 2, and 0·560 (0·497-0·645) to 0·692 (0·570-0·708) at visit 3 in validation cohort 1. The PANGEA models improved prediction of monoclonal gammopathy of undetermined significance progression to multiple myeloma compared with the IMWG rolling model at visit 1 in validation cohort 2, with C-statistics increases from 0·640 (0·518-0·718) to 0·729 (0·643-0·941) for the PANGEA model (BM) and 0·670 (0·523-0·729) to 0·879 (0·586-0·938) for the PANGEA model (no BM). INTERPRETATION: Use of the PANGEA models in clinical practice will allow patients with precursor disease to receive more accurate measures of their risk of progression to multiple myeloma, thus prompting for more appropriate treatment strategies. FUNDING: SU2C Dream Team and Cancer Research UK.


Asunto(s)
Gammopatía Monoclonal de Relevancia Indeterminada , Mieloma Múltiple , Humanos , Femenino , Masculino , Estudios Retrospectivos , Algoritmos , Creatinina
12.
STAR Protoc ; 4(1): 102125, 2023 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-36853705

RESUMEN

Although neutrophils are the most abundant leukocyte in healthy individuals and impact outcomes of diseases ranging from sepsis to cancer, they remain understudied due to technical constraints of isolation, preservation, and sequencing. We present a modified Smart-Seq2 protocol for bulk RNA sequencing of neutrophils enriched from whole blood. We describe steps for neutrophil isolation, cDNA generation, library preparation, and sample purity estimation via a bioinformatic approach. Our approach permits the collection of large cohorts and enables detection of neutrophil transcriptomic subtypes. For complete details on the use and execution of this protocol, please refer to LaSalle et al. (2022)1 and Boribong et al. (2022).2.


Asunto(s)
Neutrófilos , Sepsis , Humanos , Leucocitos , Secuencia de Bases , Análisis de Secuencia de ARN
13.
Cell Rep Med ; 3(10): 100779, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36208629

RESUMEN

Mechanisms of neutrophil involvement in severe coronavirus disease 2019 (COVID-19) remain incompletely understood. Here, we collect longitudinal blood samples from 306 hospitalized COVID-19+ patients and 86 controls and perform bulk RNA sequencing of enriched neutrophils, plasma proteomics, and high-throughput antibody profiling to investigate relationships between neutrophil states and disease severity. We identify dynamic switches between six distinct neutrophil subtypes. At days 3 and 7 post-hospitalization, patients with severe disease display a granulocytic myeloid-derived suppressor cell-like gene expression signature, while patients with resolving disease show a neutrophil progenitor-like signature. Humoral responses are identified as potential drivers of neutrophil effector functions, with elevated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunoglobulin G1 (IgG1)-to-IgA1 ratios in plasma of severe patients who survived. In vitro experiments confirm that while patient-derived IgG antibodies induce phagocytosis in healthy donor neutrophils, IgA antibodies predominantly induce neutrophil cell death. Overall, our study demonstrates a dysregulated myelopoietic response in severe COVID-19 and a potential role for IgA-dominant responses contributing to mortality.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Neutrófilos , Inmunoglobulina A , Inmunoglobulina G , Fenotipo
14.
Nat Immunol ; 23(10): 1495-1506, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36151395

RESUMEN

The immune system can eliminate tumors, but checkpoints enable immune escape. Here, we identify immune evasion mechanisms using genome-scale in vivo CRISPR screens across cancer models treated with immune checkpoint blockade (ICB). We identify immune evasion genes and important immune inhibitory checkpoints conserved across cancers, including the non-classical major histocompatibility complex class I (MHC class I) molecule Qa-1b/HLA-E. Surprisingly, loss of tumor interferon-γ (IFNγ) signaling sensitizes many models to immunity. The immune inhibitory effects of tumor IFN sensing are mediated through two mechanisms. First, tumor upregulation of classical MHC class I inhibits natural killer cells. Second, IFN-induced expression of Qa-1b inhibits CD8+ T cells via the NKG2A/CD94 receptor, which is induced by ICB. Finally, we show that strong IFN signatures are associated with poor response to ICB in individuals with renal cell carcinoma or melanoma. This study reveals that IFN-mediated upregulation of classical and non-classical MHC class I inhibitory checkpoints can facilitate immune escape.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Inhibidores de Puntos de Control Inmunológico , Evasión Inmune , Interferón gamma/genética , Interferón gamma/metabolismo , Subfamília C de Receptores Similares a Lectina de Células NK
15.
J Biol Chem ; 298(8): 102204, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35772495

RESUMEN

The protozoan parasite Trypanosoma cruzi is the causative agent of American trypanosomiasis, otherwise known as Chagas disease. To survive in the host, the T. cruzi parasite needs antioxidant defense systems. One of these is a hybrid heme peroxidase, the T. cruzi ascorbate peroxidase-cytochrome c peroxidase enzyme (TcAPx-CcP). TcAPx-CcP has high sequence identity to members of the class I peroxidase family, notably ascorbate peroxidase (APX) and cytochrome c peroxidase (CcP), as well as a mitochondrial peroxidase from Leishmania major (LmP). The aim of this work was to solve the structure and examine the reactivity of the TcAPx-CcP enzyme. Low temperature electron paramagnetic resonance spectra support the formation of an exchange-coupled [Fe(IV)=O Trp233•+] compound I radical species, analogous to that used in CcP and LmP. We demonstrate that TcAPx-CcP is similar in overall structure to APX and CcP, but there are differences in the substrate-binding regions. Furthermore, the electron transfer pathway from cytochrome c to the heme in CcP and LmP is preserved in the TcAPx-CcP structure. Integration of steady state kinetic experiments, molecular dynamic simulations, and bioinformatic analyses indicates that TcAPx-CcP preferentially oxidizes cytochrome c but is still competent for oxidization of ascorbate. The results reveal that TcAPx-CcP is a credible cytochrome c peroxidase, which can also bind and use ascorbate in host cells, where concentrations are in the millimolar range. Thus, kinetically and functionally TcAPx-CcP can be considered a hybrid peroxidase.


Asunto(s)
Citocromo-c Peroxidasa , Trypanosoma cruzi , Antioxidantes , Ascorbato Peroxidasas/genética , Ascorbato Peroxidasas/metabolismo , Ácido Ascórbico/metabolismo , Enfermedad de Chagas/parasitología , Citocromo-c Peroxidasa/química , Citocromo-c Peroxidasa/genética , Citocromo-c Peroxidasa/metabolismo , Citocromos c/metabolismo , Hemo/metabolismo , Humanos , Peroxidasa/metabolismo , Peroxidasas/metabolismo , Especificidad por Sustrato , Trypanosoma cruzi/enzimología , Trypanosoma cruzi/metabolismo
16.
Nature ; 605(7910): 532-538, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35508657

RESUMEN

Within the tumour microenvironment, CD4+ T cells can promote or suppress antitumour responses through the recognition of antigens presented by human leukocyte antigen (HLA) class II molecules1,2, but how cancers co-opt these physiologic processes to achieve immune evasion remains incompletely understood. Here we performed in-depth analysis of the phenotype and tumour specificity of CD4+ T cells infiltrating human melanoma specimens, finding that exhausted cytotoxic CD4+ T cells could be directly induced by melanoma cells through recognition of HLA class II-restricted neoantigens, and also HLA class I-restricted tumour-associated antigens. CD4+ T regulatory (TReg) cells could be indirectly elicited through presentation of tumour antigens via antigen-presenting cells. Notably, numerous tumour-reactive CD4+ TReg clones were stimulated directly by HLA class II-positive melanoma and demonstrated specificity for melanoma neoantigens. This phenomenon was observed in the presence of an extremely high tumour neoantigen load, which we confirmed to be associated with HLA class II positivity through the analysis of 116 melanoma specimens. Our data reveal the landscape of infiltrating CD4+ T cells in melanoma and point to the presentation of HLA class II-restricted neoantigens and direct engagement of immunosuppressive CD4+ TReg cells as a mechanism of immune evasion that is favoured in HLA class II-positive melanoma.


Asunto(s)
Antígenos de Neoplasias , Linfocitos T CD4-Positivos , Melanoma , Neoplasias Cutáneas , Células Presentadoras de Antígenos , Antígenos de Neoplasias/inmunología , Antígenos HLA , Humanos , Melanoma/inmunología , Fenotipo , Neoplasias Cutáneas/inmunología , Células Tumorales Cultivadas , Microambiente Tumoral
18.
Cell Rep Med ; 3(2): 100500, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35243413

RESUMEN

Immune checkpoint blockade (CPB) improves melanoma outcomes, but many patients still do not respond. Tumor mutational burden (TMB) and tumor-infiltrating T cells are associated with response, and integrative models improve survival prediction. However, integrating immune/tumor-intrinsic features using data from a single assay (DNA/RNA) remains underexplored. Here, we analyze whole-exome and bulk RNA sequencing of tumors from new and published cohorts of 189 and 178 patients with melanoma receiving CPB, respectively. Using DNA, we calculate T cell and B cell burdens (TCB/BCB) from rearranged TCR/Ig sequences and find that patients with TMBhigh and TCBhigh or BCBhigh have improved outcomes compared to other patients. By combining pairs of immune- and tumor-expressed genes, we identify three gene pairs associated with response and survival, which validate in independent cohorts. The top model includes lymphocyte-expressed MAP4K1 and tumor-expressed TBX3. Overall, RNA or DNA-based models combining immune and tumor measures improve predictions of melanoma CPB outcomes.


Asunto(s)
Melanoma , Transcriptoma , Humanos , Melanoma/tratamiento farmacológico , ARN , Análisis de Secuencia de ARN , Transcriptoma/genética , Secuenciación del Exoma
19.
Prostate ; 82(5): 584-597, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35084050

RESUMEN

BACKGROUND: Primary and metastatic prostate cancers have low mutation rates and recurrent alterations in a small set of genes, enabling targeted sequencing of prostate cancer-associated genes as an efficient approach to characterizing patient samples (compared to whole-exome and whole-genome sequencing). For example, targeted sequencing provides a flexible, rapid, and cost-effective method for genomic assessment of patient-derived cell lines to evaluate fidelity to initial patient tumor samples. METHODS: We developed a prostate cancer-specific targeted next-generation sequencing (NGS) panel to detect alterations in 62 prostate cancer-associated genes as well as recurring gene fusions with ETS family members, representing the majority of common alterations in prostate cancer. We tested this panel on primary prostate cancer tissues and blood biopsies from patients with metastatic prostate cancer. We generated patient-derived cell lines from primary prostate cancers using conditional reprogramming methods and applied targeted sequencing to evaluate the fidelity of these cell lines to the original patient tumors. RESULTS: The prostate cancer-specific panel identified biologically and clinically relevant alterations, including point mutations in driver oncogenes and ETS family fusion genes, in tumor tissues from 29 radical prostatectomy samples. The targeted panel also identified genomic alterations in cell-free DNA and circulating tumor cells (CTCs) from patients with metastatic prostate cancer, and in standard prostate cancer cell lines. We used the targeted panel to sequence our set of patient-derived cell lines; however, no prostate cancer-specific mutations were identified in the tumor-derived cell lines, suggesting preferential outgrowth of normal prostate epithelial cells. CONCLUSIONS: We evaluated a prostate cancer-specific targeted NGS panel to detect common and clinically relevant alterations (including ETS family gene fusions) in prostate cancer. The panel detected driver mutations in a diverse set of clinical samples of prostate cancer, including fresh-frozen tumors, cell-free DNA, CTCs, and cell lines. Targeted sequencing of patient-derived cell lines highlights the challenge of deriving cell lines from primary prostate cancers and the importance of genomic characterization to credential candidate cell lines. Our study supports that a prostate cancer-specific targeted sequencing panel provides an efficient, clinically feasible approach to identify genetic alterations across a spectrum of prostate cancer samples and cell lines.


Asunto(s)
Ácidos Nucleicos Libres de Células , Neoplasias de la Próstata , Línea Celular , Habilitación Profesional , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Mutación , Neoplasias de la Próstata/genética
20.
Anat Sci Educ ; 15(6): 993-1006, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34314569

RESUMEN

Anatomical education in the United Kingdom (UK) and Ireland has long been under scrutiny, especially since the reforms triggered in 1993 by the General Medical Council's "Tomorrow's Doctors." The aim of the current study was to investigate the state of medical student anatomy education in the UK and Ireland in 2019. In all, 39 medical schools completed the survey (100% response rate) and trained 10,093 medical students per year cohort. The teachers comprised 760 individuals, of these 143 were employed on full-time teaching contracts and 103 were employed on education and research contracts. Since a previous survey in 1999, the number of part-time staff has increased by 300%, including a significant increase in the number of anatomy demonstrators. In 2019, anatomy was predominantly taught to medical students in either a system-based or hybrid curriculum. In all, 34 medical schools (87%) used human cadavers to teach anatomy, with a total of 1,363 donors being used per annum. Gross anatomy teaching was integrated with medical imaging in 95% of medical schools, embryology in 81%, living anatomy in 78%, neuroanatomy in 73%, and histology in 68.3%. Throughout their five years of study, medical students are allocated on average 85 h of taught time for gross anatomy, 24 h for neuroanatomy, 24 h for histology, 11 h for living anatomy, and 10 for embryology. In the past 20 years, there has been an average loss of 39 h dedicated to gross anatomy teaching and a reduction in time dedicated to all other anatomy sub-disciplines.


Asunto(s)
Anatomía , Educación de Pregrado en Medicina , Estudiantes de Medicina , Humanos , Educación de Pregrado en Medicina/métodos , Anatomía/educación , Irlanda , Estudios de Seguimiento , Curriculum , Encuestas y Cuestionarios , Reino Unido , Enseñanza
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