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1.
Nat Immunol ; 21(10): 1205-1218, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32839608

RESUMO

Immune-modulating therapies have revolutionized the treatment of chronic diseases, particularly cancer. However, their success is restricted and there is a need to identify new therapeutic targets. Here, we show that natural killer cell granule protein 7 (NKG7) is a regulator of lymphocyte granule exocytosis and downstream inflammation in a broad range of diseases. NKG7 expressed by CD4+ and CD8+ T cells played key roles in promoting inflammation during visceral leishmaniasis and malaria-two important parasitic diseases. Additionally, NKG7 expressed by natural killer cells was critical for controlling cancer initiation, growth and metastasis. NKG7 function in natural killer and CD8+ T cells was linked with their ability to regulate the translocation of CD107a to the cell surface and kill cellular targets, while NKG7 also had a major impact on CD4+ T cell activation following infection. Thus, we report a novel therapeutic target expressed on a range of immune cells with functions in different immune responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Inflamação/imunologia , Células Matadoras Naturais/imunologia , Leishmania donovani/fisiologia , Leishmaniose Visceral/imunologia , Malária/imunologia , Proteínas de Membrana/metabolismo , Plasmodium/fisiologia , Animais , Células Cultivadas , Citotoxicidade Imunológica , Modelos Animais de Doenças , Exocitose , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Vesículas Secretórias/metabolismo
3.
Immunity ; 53(3): 564-580.e9, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32750334

RESUMO

Tumor immune escape limits durable responses to T cell therapy. Here, we examined how regulation and function of gene products that provide the target epitopes for CD8+ T cell anti-tumor immunity influence therapeutic efficacy and resistance. We used a CRISPR-Cas9-based method (CRISPitope) in syngeneic melanoma models to fuse the same model CD8+ T cell epitope to the C-termini of different endogenous gene products. Targeting melanosomal proteins or oncogenic CDK4R24C (Cyclin-dependent kinase 4) by adoptive cell transfer (ACT) of the same epitope-specific CD8+ T cells revealed diverse genetic and non-genetic immune escape mechanisms. ACT directed against melanosomal proteins, but not CDK4R24C, promoted melanoma dedifferentiation, and increased myeloid cell infiltration. CDK4R24C antigen persistence was associated with an interferon-high and T-cell-rich tumor microenvironment, allowing for immune checkpoint inhibition as salvage therapy. Thus, the choice of target antigen determines the phenotype and immune contexture of recurrent melanomas, with implications to the design of cancer immunotherapies.


Assuntos
Transferência Adotiva/métodos , Linfócitos T CD8-Positivos/transplante , Epitopos de Linfócito T/imunologia , Melanoma/imunologia , Melanoma/terapia , Evasão Tumoral/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Terapia Baseada em Transplante de Células e Tecidos/métodos , Epitopos de Linfócito T/genética , Técnicas de Inativação de Genes , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/citologia , Células Mieloides/imunologia , Microambiente Tumoral/imunologia
4.
Immunity ; 53(4): 824-839.e10, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33053331

RESUMO

CD8+ T cells within the tumor microenvironment (TME) are exposed to various signals that ultimately determine functional outcomes. Here, we examined the role of the co-activating receptor CD226 (DNAM-1) in CD8+ T cell function. The absence of CD226 expression identified a subset of dysfunctional CD8+ T cells present in peripheral blood of healthy individuals. These cells exhibited reduced LFA-1 activation, altered TCR signaling, and a distinct transcriptomic program upon stimulation. CD226neg CD8+ T cells accumulated in human and mouse tumors of diverse origin through an antigen-specific mechanism involving the transcriptional regulator Eomesodermin (Eomes). Despite similar expression of co-inhibitory receptors, CD8+ tumor-infiltrating lymphocyte failed to respond to anti-PD-1 in the absence of CD226. Immune checkpoint blockade efficacy was hampered in Cd226-/- mice. Anti-CD137 (4-1BB) agonists also stimulated Eomes-dependent CD226 loss that limited the anti-tumor efficacy of this treatment. Thus, CD226 loss restrains CD8+ T cell function and limits the efficacy of cancer immunotherapy.


Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias/imunologia , Proteínas com Domínio T/imunologia , Animais , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Receptor de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Transcriptoma/imunologia , Microambiente Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
5.
Immunity ; 53(4): 805-823.e15, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33053330

RESUMO

The activating receptor CD226 is expressed on lymphocytes, monocytes, and platelets and promotes anti-tumor immunity in pre-clinical models. Here, we examined the role of CD226 in the function of tumor-infiltrating lymphocytes (TILs) and resistance to immunotherapy. In murine tumors, a large proportion of CD8+ TILs had decreased surface expression of CD226 and exhibited features of dysfunction, whereas CD226hi TILs were highly functional. This correlation was seen also in TILs isolated from HNSCC patients. Mutation of CD226 at tyrosine 319 (Y319) led to increased CD226 surface expression, enhanced anti-tumor immunity and improved efficacy of immune checkpoint blockade (ICB). Mechanistically, tumor-derived CD155, the ligand for CD226, initiated phosphorylation of Y319 by Src kinases, thereby enabling ubiquitination of CD226 by CBL-B, internalization, and proteasomal degradation. In pre-treatment samples from melanoma patients, CD226+CD8+ T cells correlated with improved progression-free survival following ICB. Our findings argue for the development of therapies aimed at maintaining the expression of CD226.


Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Receptores Virais/imunologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Imunoterapia/métodos , Células Jurkat , Linfócitos do Interstício Tumoral/imunologia , Masculino , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos C57BL
6.
J Pediatr Hematol Oncol ; 46(5): e354-e359, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38652069

RESUMO

We report 5 children with bone marrow failure (BMF) after primary varicella zoster virus (VZV) infection or VZV vaccination, highlighting the highly variable course. Two patients were treated with intravenous immunoglobulins; one had a slow hematologic recovery, and the other was rescued by allogeneic hematopoietic stem cell transplantation (HSCT). Of the 2 patients treated with immunosuppressive therapy with antithymocyte globulin and cyclosporine, one had a complete response, and the other was transplanted for nonresponse. One patient underwent a primary allograft. All patients are alive. This study demonstrated that VZV-associated BMF is a life-threatening disorder that often requires HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Infecção pelo Vírus da Varicela-Zoster , Humanos , Masculino , Feminino , Criança , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pré-Escolar , Herpesvirus Humano 3 , Transtornos da Insuficiência da Medula Óssea/etiologia , Vacinação/efeitos adversos , Doenças da Medula Óssea/etiologia , Vacina contra Varicela/efeitos adversos , Adolescente , Imunoglobulinas Intravenosas/uso terapêutico , Lactente
7.
Am J Bioeth ; 24(7): 13-26, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38226965

RESUMO

When making substituted judgments for incapacitated patients, surrogates often struggle to guess what the patient would want if they had capacity. Surrogates may also agonize over having the (sole) responsibility of making such a determination. To address such concerns, a Patient Preference Predictor (PPP) has been proposed that would use an algorithm to infer the treatment preferences of individual patients from population-level data about the known preferences of people with similar demographic characteristics. However, critics have suggested that even if such a PPP were more accurate, on average, than human surrogates in identifying patient preferences, the proposed algorithm would nevertheless fail to respect the patient's (former) autonomy since it draws on the 'wrong' kind of data: namely, data that are not specific to the individual patient and which therefore may not reflect their actual values, or their reasons for having the preferences they do. Taking such criticisms on board, we here propose a new approach: the Personalized Patient Preference Predictor (P4). The P4 is based on recent advances in machine learning, which allow technologies including large language models to be more cheaply and efficiently 'fine-tuned' on person-specific data. The P4, unlike the PPP, would be able to infer an individual patient's preferences from material (e.g., prior treatment decisions) that is in fact specific to them. Thus, we argue, in addition to being potentially more accurate at the individual level than the previously proposed PPP, the predictions of a P4 would also more directly reflect each patient's own reasons and values. In this article, we review recent discoveries in artificial intelligence research that suggest a P4 is technically feasible, and argue that, if it is developed and appropriately deployed, it should assuage some of the main autonomy-based concerns of critics of the original PPP. We then consider various objections to our proposal and offer some tentative replies.


Assuntos
Julgamento , Preferência do Paciente , Humanos , Autonomia Pessoal , Algoritmos , Aprendizado de Máquina/ética , Tomada de Decisões/ética
8.
J Med Ethics ; 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730418

RESUMO

Artificial intelligence is currently changing many areas of society. Especially in health, where critical decisions are made, questions of control must be renegotiated: who is in control when an automated system makes clinically relevant decisions? Increasingly, the concept of meaningful human control (MHC) is being invoked for this purpose. However, it is unclear exactly how this concept is to be understood in health. Through a systematic review, we present the current state of the concept of MHC in health. The results show that there is not yet a robust MHC concept for health. We propose a broader understanding of MHC along three strands of action: enabling, exercising and evaluating control. Taking into account these strands of action and the established rules and processes in the different health sectors, the MHC concept needs to be further developed to avoid falling into two gaps, which we have described as theoretical and labelling gaps.

9.
Sci Eng Ethics ; 29(3): 21, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237246

RESUMO

Critics currently argue that applied ethics approaches to artificial intelligence (AI) are too principles-oriented and entail a theory-practice gap. Several applied ethical approaches try to prevent such a gap by conceptually translating ethical theory into practice. In this article, we explore how the currently most prominent approaches of AI ethics translate ethics into practice. Therefore, we examine three approaches to applied AI ethics: the embedded ethics approach, the ethically aligned approach, and the Value Sensitive Design (VSD) approach. We analyze each of these three approaches by asking how they understand and conceptualize theory and practice. We outline the conceptual strengths as well as their shortcomings: an embedded ethics approach is context-oriented but risks being biased by it; ethically aligned approaches are principles-oriented but lack justification theories to deal with trade-offs between competing principles; and the interdisciplinary Value Sensitive Design approach is based on stakeholder values but needs linkage to political, legal, or social governance aspects. Against this background, we develop a meta-framework for applied AI ethics conceptions with three dimensions. Based on critical theory, we suggest these dimensions as starting points to critically reflect on the conceptualization of theory and practice. We claim, first, that the inclusion of the dimension of affects and emotions in the ethical decision-making process stimulates reflections on vulnerabilities, experiences of disregard, and marginalization already within the AI development process. Second, we derive from our analysis that considering the dimension of justifying normative background theories provides both standards and criteria as well as guidance for prioritizing or evaluating competing principles in cases of conflict. Third, we argue that reflecting the governance dimension in ethical decision-making is an important factor to reveal power structures as well as to realize ethical AI and its application because this dimension seeks to combine social, legal, technical, and political concerns. This meta-framework can thus serve as a reflective tool for understanding, mapping, and assessing the theory-practice conceptualizations within AI ethics approaches to address and overcome their blind spots.


Assuntos
Inteligência Artificial , Emoções , Teoria Ética
10.
Recent Results Cancer Res ; 218: 47-66, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34019162

RESUMO

This article is a revised version of our proposal for the establishment of the legal concept of risk-adjusted prevention in the German healthcare system to regulate access to risk-reduction measures for persons at high and moderate genetic cancer risk (Meier et al. Risikoadaptierte Prävention'. Governance Perspective für Leistungsansprüche bei genetischen (Brustkrebs-)Risiken, Springer, Wiesbaden, 2018). The German context specifics are summarized to enable the source text to be used for other country-specific healthcare systems. Establishing such a legal concept is relevant to all universal and free healthcare systems similar to Germany's. Disease risks can be determined with increasing precision using bioinformatics and biostatistical innovations ('big data'), due to the identification of pathogenic germ line mutations in cancer risk genes as well as non-genetic factors and their interactions. These new technologies open up opportunities to adapt therapeutic and preventive measures to the individual risk profile of complex diseases in a way that was previously unknown, enabling not only adequate treatment but in the best case, prevention. Access to risk-reduction measures for carriers of genetic risks is generally not regulated in healthcare systems that guarantee universal and equal access to healthcare benefits. In many countries, including Austria, Denmark, the UK and the US, entitlement to benefits is essentially linked to the treatment of already manifest disease. Issues around claiming benefits for prophylactic measures involve not only evaluation of clinical options (genetic diagnostics, chemoprevention, risk-reduction surgery), but the financial cost and-from a social ethics perspective-the relationship between them. Section 1 of this chapter uses the specific example of hereditary breast cancer to show why from a medical, social-legal, health-economic and socio-ethical perspective, regulated entitlement to benefits is necessary for persons at high and moderate risk of cancer. Section 2 discusses the medical needs of persons with genetic cancer risks and goes on to develop the healthy sick model which is able to integrate the problems of the different disciplines into one scheme and to establish criteria for the legal acknowledgement of persons at high and moderate (breast cancer) risks. In the German context, the social-legal categories of classical therapeutic medicine do not adequately represent preventive measures as a regular service within the healthcare system. We propose risk-adjusted prevention as a new legal concept based on the heuristic healthy sick model. This category can serve as a legal framework for social law regulation in the case of persons with genetic cancer risks. Risk-adjusted prevention can be established in principle in any healthcare system. Criteria are also developed in relation to risk collectives and allocation (Sects. 3, 4, 5).


Assuntos
Neoplasias da Mama , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Humanos , Oncogenes
12.
J Med Ethics ; 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33722986

RESUMO

Simulations are used in very different contexts and for very different purposes. An emerging development is the possibility of using simulations to obtain a more or less representative reproduction of organs or even entire persons. Such simulations are framed and discussed using the term 'digital twin'. This paper unpacks and scrutinises the current use of such digital twins in medicine and the ideas embedded in this practice. First, the paper maps the different types of digital twins. A special focus is put on the concrete challenges inherent in the interactions between persons and their digital twin. Second, the paper addresses the questions of how far a digital twin can represent a person and what the consequences of this may be. Against the background of these two analytical steps, the paper defines first conditions for digital twins to take on an ethically justifiable form of representation.

13.
Curr Pain Headache Rep ; 25(1): 3, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33443676

RESUMO

PURPOSE OF REVIEW: We review the relevance of quantitative sensory testing (QST) in light of acute and chronic postoperative pain and associated challenges. RECENT FINDINGS: Predicting the occurrence of acute and chronic postoperative pain with QST can help identify patients at risk and allows proactive preventive management. Generally, central QST testing, such as temporal summation of pain (TSP) and conditioned pain modulation (CPM), appear to be the most promising modalities for reliable prediction of postoperative pain by QST. Overall, QST testing has the best predictive value in patients undergoing orthopedic procedures. Current evidence underlines the potential of preoperative QST to predict postoperative pain in patients undergoing elective surgery. Implementing QST in routine preoperative screening can help advancing traditional pain therapy toward personalized perioperative pain medicine.


Assuntos
Limiar da Dor/fisiologia , Dor Pós-Operatória/fisiopatologia , Somação de Potenciais Pós-Sinápticos/fisiologia , Humanos , Manejo da Dor , Dor Pós-Operatória/terapia , Medição de Risco
14.
Nature ; 565(7741): 567, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30700876
15.
J Med Ethics ; 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245804

RESUMO

Making good decisions in extremely complex and difficult processes and situations has always been both a key task as well as a challenge in the clinic and has led to a large amount of clinical, legal and ethical routines, protocols and reflections in order to guarantee fair, participatory and up-to-date pathways for clinical decision-making. Nevertheless, the complexity of processes and physical phenomena, time as well as economic constraints and not least further endeavours as well as achievements in medicine and healthcare continuously raise the need to evaluate and to improve clinical decision-making. This article scrutinises if and how clinical decision-making processes are challenged by the rise of so-called artificial intelligence-driven decision support systems (AI-DSS). In a first step, this article analyses how the rise of AI-DSS will affect and transform the modes of interaction between different agents in the clinic. In a second step, we point out how these changing modes of interaction also imply shifts in the conditions of trustworthiness, epistemic challenges regarding transparency, the underlying normative concepts of agency and its embedding into concrete contexts of deployment and, finally, the consequences for (possible) ascriptions of responsibility. Third, we draw first conclusions for further steps regarding a 'meaningful human control' of clinical AI-DSS.

16.
Philos Trans A Math Phys Eng Sci ; 376(2122)2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29760120

RESUMO

The coasts of the West Antarctic Peninsula are strongly influenced by glacier meltwater discharge. The spatial structure and biogeochemical composition of inshore habitats are shaped by large quantities of terrigenous particulate material deposited in the vicinity of the coast, which impacts the pelagic and benthic ecosystems. We used a multitude of geochemical and environmental variables to identify the radius extension of the meltwater impact from the Fourcade Glacier into the fjord system of Potter Cove, King George Island. The k-means cluster algorithm, canonical correspondence analysis, variance analysis and Tukey's post hoc multiple comparison tests were applied to define and cluster coastal meltwater habitats. A minimum of 10 clusters were needed to classify the 8 km2 study area into meltwater fjord habitats (MFHs), fjord habitats and marine habitats. Strontium content in surface sediments is the main geochemical indicator for lithogenic creek discharge in Potter Cove. Furthermore, bathymetry, glacier distance and geomorphic positioning are the essential habitats explaining variables. The mean and maximum MFH extent amounted to 1 km and 2 km, respectively. Extrapolation of the identified meltwater impact ranges to King George Island coastlines, which are presently ice-covered bays and fjord areas, indicated an overall coverage of 200-400 km2 MFH, underpinning the importance of better understanding the biology and biogeochemistry in terrestrial marine transition zones.This article is part of the theme issue 'The marine system of the West Antarctic Peninsula: status and strategy for progress in a region of rapid change'.

18.
Glycobiology ; 27(4): 342-357, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27986835

RESUMO

Tannerella forsythia is an anaerobic, Gram-negative periodontal pathogen. A unique O-linked oligosaccharide decorates the bacterium's cell surface proteins and was shown to modulate the host immune response. In our study, we investigated the biosynthesis of the nonulosonic acid (NulO) present at the terminal position of this glycan. A bioinformatic analysis of T. forsythia genomes revealed a gene locus for the synthesis of pseudaminic acid (Pse) in the type strain ATCC 43037 while strains FDC 92A2 and UB4 possess a locus for the synthesis of legionaminic acid (Leg) instead. In contrast to the NulO in ATCC 43037, which has been previously identified as a Pse derivative (5-N-acetimidoyl-7-N-glyceroyl-3,5,7,9-tetradeoxy-l-glycero-l-manno-NulO), glycan analysis of strain UB4 performed in this study indicated a 350-Da, possibly N-glycolyl Leg (3,5,7,9-tetradeoxy-d-glycero-d-galacto-NulO) derivative with unknown C5,7 N-acyl moieties. We have expressed, purified and characterized enzymes of both NulO pathways to confirm these genes' functions. Using capillary electrophoresis (CE), CE-mass spectrometry and NMR spectroscopy, our studies revealed that Pse biosynthesis in ATCC 43037 essentially follows the UDP-sugar route described in Helicobacter pylori, while the pathway in strain FDC 92A2 corresponds to Leg biosynthesis in Campylobacter jejuni involving GDP-sugar intermediates. To demonstrate that the NulO biosynthesis enzymes are functional in vivo, we created knockout mutants resulting in glycans lacking the respective NulO. Compared to the wild-type strains, the mutants exhibited significantly reduced biofilm formation on mucin-coated surfaces, suggestive of their involvement in host-pathogen interactions or host survival. This study contributes to understanding possible biological roles of bacterial NulOs.


Assuntos
Vias Biossintéticas/genética , Proteínas de Membrana/genética , Tannerella forsythia/genética , Genoma Bacteriano/genética , Glicosilação , Interações Hospedeiro-Patógeno/genética , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Oligossacarídeos/genética , Oligossacarídeos/metabolismo , Ácidos Siálicos/biossíntese , Açúcares Ácidos/metabolismo , Tannerella forsythia/enzimologia , Tannerella forsythia/patogenicidade
19.
J Med Ethics ; 48(9): 579-580, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34380743
20.
Bioethics ; 31(5): 409-417, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28182296

RESUMO

According to the judgement of the European Court of Justice in 2014, human parthenogenetic stem cells are excluded from the patenting prohibition of procedures based on hESC by the European Biopatent Directive, because human parthenotes are not human embryos. This article is based on the thesis that in light of the technological advances in the field of stem cell research, the attribution of the term 'human embryo' to certain entities on a descriptive level as well as the attribution of a normative protection status to certain entities based on the criterion of totipotency, are becoming increasingly unclear. The example of human parthenotes in particular demonstrates that totipotency is not at all a necessary condition for the attribution of the term 'human embryo'. Furthermore, the example of hiPSC and somatic cells particularly shows that totipotency is also not a sufficient condition for the attribution of a normative protection status to certain entities. Therefore, it is not a suitable criterion for distinguishing between human embryos worthy of protection and human non-embryos not worthy of protection. Consequently, this conclusion has repercussions for the patenting question. The strict delineation between an ethically problematic commercial use of human embryos and the concomitant patenting prohibition of hESC-based procedures and an ethically unproblematic commercial use of human non-embryos and the therefore either unrestrictedly permitted (cf. human parthenotes) or even unregulated (cf. hiPSC) patenting of procedures based on these alleged alternatives becomes increasingly blurred.


Assuntos
Células-Tronco Embrionárias , Células-Tronco Pluripotentes Induzidas , Partenogênese , Pesquisa com Células-Tronco/ética , Embrião de Mamíferos/fisiologia , Europa (Continente) , Humanos , Patentes como Assunto
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