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1.
Trends Immunol ; 44(10): 748-750, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37652814

RESUMO

Broadening immune responses through antigen spreading remains the 'Holy Grail' of cancer immunotherapy. A study by Ma and colleagues reveals that vaccine boosting of chimeric antigen receptor (CAR)-T cells in mice promotes endogenous immunity and elicits antigen spread to eliminate antigenically heterogenous solid tumors through a mechanism crucially dependent on interferon (IFN)γ.


Assuntos
Neoplasias , Receptores de Antígenos de Linfócitos T , Camundongos , Animais , Imunoterapia Adotiva , Neoplasias/terapia , Linfócitos T
2.
PLoS Comput Biol ; 20(5): e1012106, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38748755

RESUMO

Contrast transport models are widely used to quantify blood flow and transport in dynamic contrast-enhanced magnetic resonance imaging. These models analyze the time course of the contrast agent concentration, providing diagnostic and prognostic value for many biological systems. Thus, ensuring accuracy and repeatability of the model parameter estimation is a fundamental concern. In this work, we analyze the structural and practical identifiability of a class of nested compartment models pervasively used in analysis of MRI data. We combine artificial and real data to study the role of noise in model parameter estimation. We observe that although all the models are structurally identifiable, practical identifiability strongly depends on the data characteristics. We analyze the impact of increasing data noise on parameter identifiability and show how the latter can be recovered with increased data quality. To complete the analysis, we show that the results do not depend on specific tissue characteristics or the type of enhancement patterns of contrast agent signal.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Meios de Contraste/química , Meios de Contraste/farmacocinética , Imageamento por Ressonância Magnética/métodos , Humanos , Modelos Biológicos , Biologia Computacional , Simulação por Computador
3.
Proc Natl Acad Sci U S A ; 119(33): e2112006119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35939683

RESUMO

IL13Rα2 is an attractive target due to its overexpression in a variety of cancers and rare expression in healthy tissue, motivating expansion of interleukin 13 (IL13)-based chimeric antigen receptor (CAR) T cell therapy from glioblastoma into systemic malignancies. IL13Rα1, the other binding partner of IL13, is ubiquitously expressed in healthy tissue, raising concerns about the therapeutic window of systemic administration. IL13 mutants with diminished binding affinity to IL13Rα1 were previously generated by structure-guided protein engineering. In this study, two such variants, termed C4 and D7, are characterized for their ability to mediate IL13Rα2-specific response as binding domains for CAR T cells. Despite IL13Rα1 and IL13Rα2 sharing similar binding interfaces on IL13, mutations to IL13 that decrease binding affinity for IL13Rα1 did not drastically change binding affinity for IL13Rα2. Micromolar affinity to IL13Rα1 was sufficient to pacify IL13-mutein CAR T cells in the presence of IL13Rα1-overexpressing cells in vitro. Interestingly, effector activity of D7 CAR T cells, but not C4 CAR T cells, was demonstrated when cocultured with IL13Rα1/IL4Rα-coexpressing cancer cells. While low-affinity interactions with IL13Rα1 did not result in observable toxicities in mice, in vivo biodistribution studies demonstrated that C4 and D7 CAR T cells were better able to traffic away from IL13Rα1+ lung tissue than were wild-type (WT) CAR T cells. These results demonstrate the utility of structure-guided engineering of ligand-based binding domains with appropriate selectivity while validating IL13-mutein CARs with improved selectivity for application to systemic IL13Rα2-expressing malignancies.


Assuntos
Imunoterapia Adotiva , Subunidade alfa2 de Receptor de Interleucina-13 , Interleucina-13 , Neoplasias , Animais , Linhagem Celular Tumoral , Humanos , Imunoterapia Adotiva/métodos , Interleucina-13/genética , Interleucina-13/farmacocinética , Interleucina-13/uso terapêutico , Subunidade alfa2 de Receptor de Interleucina-13/antagonistas & inibidores , Camundongos , Neoplasias/terapia , Engenharia de Proteínas , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Age Ageing ; 53(6)2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38851216

RESUMO

OBJECTIVES: To investigate if a prospective feedback loop that flags older patients at risk of death can reduce non-beneficial treatment at end of life. DESIGN: Prospective stepped-wedge cluster randomised trial with usual care and intervention phases. SETTING: Three large tertiary public hospitals in south-east Queensland, Australia. PARTICIPANTS: 14 clinical teams were recruited across the three hospitals. Teams were recruited based on a consistent history of admitting patients aged 75+ years, and needed a nominated lead specialist consultant. Under the care of these teams, there were 4,268 patients (median age 84 years) who were potentially near the end of life and flagged at risk of non-beneficial treatment. INTERVENTION: The intervention notified clinicians of patients under their care determined as at-risk of non-beneficial treatment. There were two notification flags: a real-time notification and an email sent to clinicians about the at-risk patients at the end of each screening day. The nudge intervention ran for 16-35 weeks across the three hospitals. MAIN OUTCOME MEASURES: The primary outcome was the proportion of patients with one or more intensive care unit (ICU) admissions. The secondary outcomes examined times from patients being flagged at-risk. RESULTS: There was no improvement in the primary outcome of reduced ICU admissions (mean probability difference [intervention minus usual care] = -0.01, 95% confidence interval -0.08 to 0.01). There were no differences for the times to death, discharge, or medical emergency call. There was a reduction in the probability of re-admission to hospital during the intervention phase (mean probability difference -0.08, 95% confidence interval -0.13 to -0.03). CONCLUSIONS: This nudge intervention was not sufficient to reduce the trial's non-beneficial treatment outcomes in older hospital patients. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry, ACTRN12619000675123 (registered 6 May 2019).


Assuntos
Assistência Terminal , Humanos , Masculino , Idoso de 80 Anos ou mais , Feminino , Idoso , Assistência Terminal/métodos , Estudos Prospectivos , Queensland , Unidades de Terapia Intensiva , Futilidade Médica , Retroalimentação , Admissão do Paciente , Fatores Etários , Medição de Risco
5.
BMC Geriatr ; 24(1): 202, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38413877

RESUMO

BACKGROUND: Non-beneficial treatment affects a considerable proportion of older people in hospital, and some will choose to decline invasive treatments when they are approaching the end of their life. The Intervention for Appropriate Care and Treatment (InterACT) intervention was a 12-month stepped wedge randomised controlled trial with an embedded process evaluation in three hospitals in Brisbane, Australia. The aim was to increase appropriate care and treatment decisions for older people at the end-of-life, through implementing a nudge intervention in the form of a prospective feedback loop. However, the trial results indicated that the expected practice change did not occur. The process evaluation aimed to assess implementation using the Consolidated Framework for Implementation Research, identify barriers and enablers to implementation and provide insights into the lack of effect of the InterACT intervention. METHODS: Qualitative data collection involved 38 semi-structured interviews with participating clinicians, members of the executive advisory groups overseeing the intervention at a site level, clinical auditors, and project leads. Online interviews were conducted at two times: implementation onset and completion. Data were coded to the Consolidated Framework for Implementation Research and deductively analysed. RESULTS: Overall, clinicians felt the premise and clinical reasoning behind InterACT were strong and could improve patient management. However, several prominent barriers affected implementation. These related to the potency of the nudge intervention and its integration into routine clinical practice, clinician beliefs and perceived self-efficacy, and wider contextual factors at the health system level. CONCLUSIONS: An intervention designed to change clinical practice for patients at or near to end-of-life did not have the intended effect. Future interventions targeting this area of care should consider using multi-component strategies that address the identified barriers to implementation and clinician change of practice. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry (ANZCTR), ACTRN12619000675123p (approved 06/05/2019).


Assuntos
Morte , Pacientes , Idoso , Humanos , Austrália/epidemiologia , Hospitais , Estudos Prospectivos
6.
Mol Cancer ; 22(1): 183, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974170

RESUMO

Chimeric antigen receptor (CAR) NK and T cell therapy are promising immunotherapeutic approaches for the treatment of cancer. However, the efficacy of CAR NK/T cell therapy is often hindered by various factors, including the phenomenon of trogocytosis, which involves the bidirectional exchange of membrane fragments between cells. In this review, we explore the role of trogocytosis in CAR NK/T cell therapy and highlight potential strategies for its modulation to improve therapeutic efficacy. We provide an in-depth analysis of trogocytosis as it relates to the fate and function of NK and T cells, focusing on its effects on cell activation, cytotoxicity, and antigen presentation. We discuss how trogocytosis can mediate transient antigen loss on cancer cells, thereby negatively affecting the effector function of CAR NK/T cells. Additionally, we address the phenomenon of fratricide and trogocytosis-associated exhaustion, which can limit the persistence and effectiveness of CAR-expressing cells. Furthermore, we explore how trogocytosis can impact CAR NK/T cell functionality, including the acquisition of target molecules and the modulation of signaling pathways. To overcome the negative effects of trogocytosis on cellular immunotherapy, we propose innovative approaches to modulate trogocytosis and augment CAR NK/T cell therapy. These strategies encompass targeting trogocytosis-related molecules, engineering CAR NK/T cells to resist trogocytosis-induced exhaustion and leveraging trogocytosis to enhance the function of CAR-expressing cells. By overcoming the limitations imposed by trogocytosis, it may be possible to unleash the full potential of CAR NK/T therapy against cancer. The knowledge and strategies presented in this review will guide future research and development, leading to improved therapeutic outcomes in the field of immunotherapy.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Células Matadoras Naturais , Trogocitose , Imunoterapia Adotiva , Linfócitos T , Receptores de Antígenos Quiméricos/metabolismo , Neoplasias/metabolismo , Terapia Baseada em Transplante de Células e Tecidos
7.
PLoS Comput Biol ; 18(1): e1009504, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35081104

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy is potentially an effective targeted immunotherapy for glioblastoma, yet there is presently little known about the efficacy of CAR T-cell treatment when combined with the widely used anti-inflammatory and immunosuppressant glucocorticoid, dexamethasone. Here we present a mathematical model-based analysis of three patient-derived glioblastoma cell lines treated in vitro with CAR T-cells and dexamethasone. Advanced in vitro experimental cell killing assay technologies allow for highly resolved temporal dynamics of tumor cells treated with CAR T-cells and dexamethasone, making this a valuable model system for studying the rich dynamics of nonlinear biological processes with translational applications. We model the system as a nonautonomous, two-species predator-prey interaction of tumor cells and CAR T-cells, with explicit time-dependence in the clearance rate of dexamethasone. Using time as a bifurcation parameter, we show that (1) dexamethasone destabilizes coexistence equilibria between CAR T-cells and tumor cells in a dose-dependent manner and (2) as dexamethasone is cleared from the system, a stable coexistence equilibrium returns in the form of a Hopf bifurcation. With the model fit to experimental data, we demonstrate that high concentrations of dexamethasone antagonizes CAR T-cell efficacy by exhausting, or reducing the activity of CAR T-cells, and by promoting tumor cell growth. Finally, we identify a critical threshold in the ratio of CAR T-cell death to CAR T-cell proliferation rates that predicts eventual treatment success or failure that may be used to guide the dose and timing of CAR T-cell therapy in the presence of dexamethasone in patients.


Assuntos
Dexametasona , Glioblastoma/metabolismo , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos/efeitos dos fármacos , Adulto , Linhagem Celular Tumoral , Dexametasona/administração & dosagem , Dexametasona/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade
8.
BMC Health Serv Res ; 23(1): 587, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286977

RESUMO

BACKGROUND: Peripheral intravenous catheters (PIVCs) are the most used invasive medical device in healthcare. Yet around half of insertion attempts are unsuccessful leading to delayed medical treatments and patient discomfort of harm. Ultrasound-guided PIVC (USGPIVC) insertion is an evidence-based intervention shown to improve insertion success especially in patients with Difficult IntraVenous Access (BMC Health Serv Res 22:220, 2022), however the implementation in some healthcare settings remains suboptimal. This study aims to co-design interventions that optimise ultrasound guided PIVC insertion in patients with DIVA, implement and evaluate these initiatives and develop scale up activities. METHODS: A stepped-wedge cluster randomized controlled trial will be conducted in three hospitals (two adult, one paediatric) in Queensland, Australia. The intervention will be rolled out across 12 distinct clusters (four per hospital). Intervention development will be guided by Michie's Behavior Change Wheel with the aim to increase local staff capability, opportunity, and motivation for appropriate, sustainable adoption of USGPIVC insertion. Eligible clusters include all wards or departments where > 10 PIVCs/week are typically inserted. All clusters will commence in the control (baseline) phase, then, one cluster per hospital will step up every two months, as feasible, to the implementation phase, where the intervention will be rolled out. Implementation strategies are tailored for each hospital by local investigators and advisory groups, through context assessments, staff surveys, and stakeholder interviews and informed by extensive consumer interviews and consultation. Outcome measures align with the RE-AIM framework including clinical-effectiveness outcomes (e.g., first-time PIVC insertion success for DIVA patients [primary outcome], number of insertion attempts); implementation outcomes (e.g., intervention fidelity, readiness assessment) and cost effectiveness outcomes. The Consolidated Framework for Implementation Research framework will be used to report the intervention as it was implemented; how people participated in and responded to the intervention; contextual influences and how the theory underpinning the intervention was realised and delivered at each site. A sustainability assessment will be undertaken at three- and six-months post intervention. DISCUSSION: Study findings will help define systematic solutions to implement DIVA identification and escalation tools aiming to address consumer dissatisfaction with current PIVC insertion practices. Such actionable knowledge is critical for implementation of scale-up activities. TRIAL REGISTRATION: Prospectively registered (Australian and New Zealand Clinical Trials Registry; ACTRN12621001497897).


Assuntos
Hospitais , Tecnologia , Adulto , Humanos , Criança , Austrália , Queensland , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Immunol Rev ; 290(1): 60-84, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31355493

RESUMO

Malignant brain tumors, including glioblastoma, represent some of the most difficult to treat of solid tumors. Nevertheless, recent progress in immunotherapy, across a broad range of tumor types, provides hope that immunological approaches will have the potential to improve outcomes for patients with brain tumors. Chimeric antigen receptors (CAR) T cells, a promising immunotherapeutic modality, utilizes the tumor targeting specificity of any antibody or receptor ligand to redirect the cytolytic potency of T cells. The remarkable clinical response rates of CD19-targeted CAR T cells and early clinical experiences in glioblastoma demonstrating safety and evidence for disease modifying activity support the potential of further advancements ultimately providing clinical benefit for patients. The brain, however, is an immune specialized organ presenting unique and specific challenges to immune-based therapies. Remaining barriers to be overcome for achieving effective CAR T cell therapy in the central nervous system (CNS) include tumor antigenic heterogeneity, an immune-suppressive microenvironment, unique properties of the CNS that limit T cell entry, and risks of immune-based toxicities in this highly sensitive organ. This review will summarize preclinical and clinical data for CAR T cell immunotherapy in glioblastoma and other malignant brain tumors, including present obstacles to advancement.


Assuntos
Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/terapia , Imunoterapia Adotiva , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Antígenos de Neoplasias/imunologia , Neoplasias Encefálicas/patologia , Engenharia Genética , Humanos , Imunidade , Imunoterapia Adotiva/métodos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos Quiméricos/genética , Resultado do Tratamento
10.
J Transl Med ; 20(1): 236, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606815

RESUMO

Harnessing the effector mechanisms of the immune system to combat brain tumors with antigen specificity and memory has been in research and clinical testing for many years. Government grant mechanisms and non-profit organizations have supported many innovative projects and trials while biotech companies have invested in the development of needed tools, assays and novel clinical approaches. The National Brain Tumor Society and the Parker Institute for Cancer Immunotherapy partnered to host a workshop to share recent data, ideas and identify both hurdles and new opportunities for harnessing immunotherapy against pediatric and adult brain tumors. Adoptively transferred cell therapies have recently shown promising early clinical results. Local cell delivery to the brain, new antigen targets and innovative engineering approaches are poised for testing in a new generation of clinical trials. Although several such advances have been made, several obstacles remain for the successful application of immunotherapies for brain tumors, including the need for more representative animal models that can better foreshadow human trial outcomes. Tumor and tumor microenvironment biopsies with multiomic analysis are critical to understand mechanisms of response and patient stratification, yet brain tumors are especially challenging for such biopsy collection. These workshop proceedings and commentary shed light on the status of immunotherapy in pediatric and adult brain tumor patients, including current research as well as opportunities for improving future efforts to bring immunotherapy to the forefront in the management of brain tumors.


Assuntos
Neoplasias Encefálicas , Imunoterapia , Adulto , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/terapia , Terapia Baseada em Transplante de Células e Tecidos , Criança , Humanos , Fatores Imunológicos/uso terapêutico , Imunoterapia/métodos , Microambiente Tumoral
11.
BMC Geriatr ; 22(1): 860, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36380290

RESUMO

BACKGROUND: Hospitalisation rates for older people are increasing, with end-of-life care becoming a more medicalised experience. Innovative approaches are warranted to support early identification of the end-of-life phase, communicate prognosis, provide care consistent with people's preferences, and improve the use of healthcare resources. The Intervention for Appropriate Care and Treatment (InterACT) trial aimed to increase appropriate care and treatment decisions for older people at the end of life, through implementation of a prospective feedback loop. This paper reports on the care review outcomes. METHODS: A stepped-wedge randomised controlled trial was conducted in three large acute hospitals in Queensland, Australia between May 2020 and June 2021. The trial identified older people nearing the end of life using two validated tools for detecting deterioration and short-term death. Admitting clinical teams were provided with details of patients identified as at-risk with the goal of increasing awareness that end of life was approaching to facilitate appropriate patient centred care and avoid non-beneficial treatment. We examined the time between when the patient was identified as 'at-risk' and three outcomes: clinician-led care review discussions, review of care directive measures and palliative care referrals. These were considered useful indicators of appropriate care at the end of life. RESULTS: In two hospitals there was a reduction in the review of care directive measures during the intervention compared with usual care at 21 days (reduced probability of - 0.08; 95% CI: - 0.12 to - 0.04 and - 0.14; 95% CI: - 0.21 to - 0.06). In one hospital there was a large reduction in clinician-led care review discussions at 21 days during the intervention (reduced probability of - 0.20; 95% CI: - 0.28 to - 0.13). There was little change in palliative care referrals in any hospital, with average probability differences at 21 days of - 0.01, 0.02 and 0.04. DISCUSSION: The results are disappointing as an intervention designed to improve care of hospitalised older people appeared to have the opposite effect on care review outcomes. The reasons for this may be a combination of the intervention design and health system challenges due to the pandemic that highlight the complexity of providing more appropriate care at the end of life. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry, ACTRN12619000675123 (registered 6 May 2019).


Assuntos
Cuidados Paliativos , Assistência Terminal , Humanos , Idoso , Retroalimentação , Estudos Prospectivos , Morte
12.
Int J Audiol ; 61(7): 531-538, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34255984

RESUMO

This clinical consensus document addresses the assessment, selection, and fitting considerations for non-surgical bone conduction hearing devices (BCHD) for children under the age of 5 years identified as having unilateral or bilateral, permanent conductive or mixed hearing losses. Children with profound unilateral sensorineural hearing losses are not addressed. The document was developed based on evidence review and consensus by The Paediatric Bone Conduction Working Group, which is composed of audiologists from North America who have experience working with BCHDs in children. The document aims to provide clinical direction for an area of paediatric audiology practice that is under development and is therefore lacking in standard protocols or guidelines. This work may serve as a basis for future research and clinical contributions to support prospective paediatric audiology practices.


Assuntos
Auxiliares de Audição , Perda Auditiva Condutiva-Neurossensorial Mista , Perda Auditiva Neurossensorial , Condução Óssea , Criança , Pré-Escolar , Consenso , Perda Auditiva Condutiva/diagnóstico , Perda Auditiva Condutiva/terapia , Humanos , Estudos Prospectivos
13.
Int J Mol Sci ; 23(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35328572

RESUMO

Immunotherapy using chimeric antigen receptor (CAR) T cells is a rapidly emerging modality that engineers T cells to redirect tumor-specific cytotoxicity. CAR T cells have been well characterized for their efficacy against B cell malignancies, and rigorously studied in other types of tumors. Preclinical evaluation of CAR T cell function, including direct tumor killing, cytokine production, and memory responses, is crucial to the development and optimization of CAR T cell therapies. Such comprehensive examinations are usually performed in different types of models. Model establishment should focus on key challenges in the clinical setting and the capability to generate reliable data to indicate CAR T cell therapeutic potency in the clinic. Further, modeling the interaction between CAR T cells and tumor microenvironment provides additional insight for the future endeavors to enhance efficacy, especially against solid tumors. This review will summarize both in vitro and in vivo models for CAR T cell functional evaluation, including how they have evolved with the needs of CAR T cell research, the information they can provide for preclinical assessment of CAR T cell products, and recent technology advances to test CAR T cells in more clinically relevant models.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva , Neoplasias/patologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T , Microambiente Tumoral
14.
J Antimicrob Chemother ; 76(6): 1532-1538, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33582800

RESUMO

OBJECTIVES: To evaluate the efficacy of a novel lantibiotic, CMB001, against MRSA biofilms in vitro and in an in vivo experimental model of bacterial infection. METHODS: Antibacterial activity of CMB001 was measured in vitro after its exposure to whole blood or to platelet-poor plasma. In vitro efficacy of CMB001 against a Staphylococcus aureus biofilm was studied using scanning electron microscopy. The maximum tolerable dose in mice was determined and a preliminary pharmacokinetic analysis for CMB001 was performed in mice. In vivo efficacy was evaluated in a neutropenic mouse thigh model of infection. RESULTS: CMB001 maintained its antibacterial activity in the presence of blood or plasma for up to 24 h at 37°C. CMB001 efficiently killed S. aureus within the biofilm by causing significant damage to the bacterial cell wall. The maximum tolerable dose in mice was established to be 10 mg/kg and could be increased to 30 mg/kg in mice pretreated with antihistamines. In neutropenic mice infected with MRSA, treatment with CMB001 reduced the bacterial burden with an efficacy equivalent to that of vancomycin. CONCLUSIONS: CMB001 offers potential as an alternative treatment option to combat MRSA. It will be of interest to evaluate the in vivo efficacy of CMB001 against infections caused by other pathogens, including Clostridioides difficile and Acinetobacter baumannii, and to expand its pharmacokinetic/pharmacodynamic parameters and safety profile.


Assuntos
Bacteriocinas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus , Vancomicina
15.
Blood ; 134(11): 880-891, 2019 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-31350267

RESUMO

Factor VIII (FVIII) pharmacokinetic (PK) properties show high interpatient variability in hemophilia A patients. Although previous studies have determined that age, body mass index, von Willebrand factor antigen (VWF:Ag) levels, and ABO blood group status can influence FVIII PK, they do not account for all observed variability. In this study, we aim to describe the genetic determinants that modify the FVIII PK profile in a population of 43 pediatric hemophilia A patients. We observed that VWF:Ag and VWF propeptide (VWFpp)/VWF:Ag, but not VWFpp, were associated with FVIII half-life. VWFpp/VWF:Ag negatively correlated with FVIII half-life in patients with non-O blood type, but no correlation was observed for type O patients, suggesting that von Willebrand factor (VWF) half-life, as modified by the ABO blood group, is a strong regulator of FVIII PK. The FVIII-binding activity of VWF positively correlated with FVIII half-life, and the rare or low-frequency nonsynonymous VWF variants p.(Arg826Lys) and p.(Arg852Glu) were identified in patients with reduced VWF:FVIIIB but not VWF:Ag. Common variants at the VWF, CLEC4M, and STAB2 loci, which have been previously associated with plasma levels of VWF and FVIII, were associated with the FVIII PK profile. Together, these studies characterize the mechanistic basis by which VWF clearance and ABO glycosylation modify FVIII PK in a pediatric population. Moreover, this study is the first to identify non-VWF and non-ABO variants that modify FVIII PK in pediatric hemophilia A patients.


Assuntos
Coagulação Sanguínea/genética , Fator VIII/farmacocinética , Hemofilia A/genética , Hemofilia A/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo , Adolescente , Testes de Coagulação Sanguínea , Criança , Fator VIII/uso terapêutico , Feminino , Variação Genética , Genótipo , Meia-Vida , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Humanos , Masculino , Taxa de Depuração Metabólica/genética , Ligação Proteica , Proteólise
16.
Nano Lett ; 20(2): 860-867, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31647675

RESUMO

Microfluidic intracellular delivery approaches based on plasma membrane poration have shown promise for addressing the limitations of conventional cellular engineering techniques in a wide range of applications in biology and medicine. However, the inherent stochasticity of the poration process in many of these approaches often results in a trade-off between delivery efficiency and cellular viability, thus potentially limiting their utility. Herein, we present a novel microfluidic device concept that mitigates this trade-off by providing opportunity for deterministic mechanoporation (DMP) of cells en masse. This is achieved by the impingement of each cell upon a single needle-like penetrator during aspiration-based capture, followed by diffusive influx of exogenous cargo through the resulting membrane pore, once the cells are released by reversal of flow. Massive parallelization enables high throughput operation, while single-site poration allows for delivery of small and large-molecule cargos in difficult-to-transfect cells with efficiencies and viabilities that exceed both conventional and emerging transfection techniques. As such, DMP shows promise for advancing cellular engineering practice in general and engineered cell product manufacturing in particular.


Assuntos
Sobrevivência Celular/fisiologia , Citoplasma/genética , Dispositivos Lab-On-A-Chip , Citoplasma/fisiologia , Difusão , Eletroporação/métodos , Humanos , Agulhas , Transfecção/métodos
17.
Physiol Genomics ; 52(10): 492-511, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32926651

RESUMO

Skeletal muscles can undergo atrophy and/or programmed cell death (PCD) during development or in response to a wide range of insults, including immobility, cachexia, and spinal cord injury. However, the protracted nature of atrophy and the presence of multiple cell types within the tissue complicate molecular analyses. One model that does not suffer from these limitations is the intersegmental muscle (ISM) of the tobacco hawkmoth Manduca sexta. Three days before the adult eclosion (emergence) at the end of metamorphosis, the ISMs initiate a nonpathological program of atrophy that results in a 40% loss of mass. The ISMs then generate the eclosion behavior and initiate a nonapoptotic PCD during the next 30 h. We have performed a comprehensive transcriptomics analysis of all mRNAs and microRNAs throughout ISM development to better understand the molecular mechanisms that mediate atrophy and death. Atrophy involves enhanced protein catabolism and reduced expression of the genes involved in respiration, adhesion, and the contractile apparatus. In contrast, PCD involves the induction of numerous proteases, DNA methylases, membrane transporters, ribosomes, and anaerobic metabolism. These changes in gene expression are largely repressed when insects are injected with the insect steroid hormone 20-hydroxyecdysone, which delays death. The expression of the death-associated proteins may be greatly enhanced by reductions in specific microRNAs that function to repress translation. This study not only provides fundamental new insights into basic developmental processes, it may also represent a powerful resource for identifying potential diagnostic markers and molecular targets for therapeutic intervention.


Assuntos
Apoptose/genética , Genes de Insetos , Manduca/genética , Atrofia Muscular/genética , Transcriptoma , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas Contráteis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , MicroRNAs/genética , Contração Muscular/genética , Músculo Esquelético/crescimento & desenvolvimento , RNA Mensageiro/genética
18.
BMC Med Educ ; 20(1): 361, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33054845

RESUMO

BACKGROUND: Primary care providers' (PCPs) attitude toward obesity is often negative, and their confidence level for helping patients manage their weight is low. Continuing professional development (CPD) on the subject of obesity is often based on a single activity using a traditional passive approach such as lectures known to have little effect on performance or patient outcomes. The aim of this study was to evaluate the impact of an educational intervention for obesity management on PCPs' attitude, self-efficacy, practice changes and patient-related outcomes. METHODS: Prospective interventional study with 12 months follow-up. A two-day clinical obesity preceptorship was offered where participants were actively involved in competence building using real-life situations, in addition to electronic networking tools, including a discussion forum and interactive monthly webinars. Thirty-five participants (12 nurses and 23 physicians) from seven Family medicine groups were enrolled. Questionnaires were used to evaluate the impact on primary care nurses' and physicians' attitudes and self-efficacy for obesity management. Practice changes and patient outcomes were evaluated using clinical vignettes, de-identified electronic patient records and qualitative analyses from group interviews. RESULTS: Physicians' general attitude towards patients with obesity was improved (61 ± 22 mm vs 85 ± 17 mm, p <  0.001). Self-efficacy for obesity management and lifestyle counselling were also improved immediately and 1 year after the intervention (all Ps <  0.05). De-identified patient records and clinical vignettes both showed improvement in recording of weight, waist circumference and evaluation of readiness to change lifestyle (all Ps <  0.05) that was confirmed by group interviews. Also, 15% of patients who were prospectively registered for weight management had lost more than 5% of their initial weight at the time of their last visit (P <  0.0001, median follow-up of 152 days). CONCLUSION: A multimodal educational intervention for obesity management can improve PCPs'attitude and self-efficacy for obesity management and lifestyle counselling. This translates into beneficial practice changes and patient-related outcomes. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01385397 . Retrospectively registered, 28 June 2011.


Assuntos
Preceptoria , Atenção Primária à Saúde , Eletrônica , Humanos , Obesidade/terapia , Estudos Prospectivos
19.
N Engl J Med ; 375(26): 2561-9, 2016 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-28029927

RESUMO

A patient with recurrent multifocal glioblastoma received chimeric antigen receptor (CAR)-engineered T cells targeting the tumor-associated antigen interleukin-13 receptor alpha 2 (IL13Rα2). Multiple infusions of CAR T cells were administered over 220 days through two intracranial delivery routes - infusions into the resected tumor cavity followed by infusions into the ventricular system. Intracranial infusions of IL13Rα2-targeted CAR T cells were not associated with any toxic effects of grade 3 or higher. After CAR T-cell treatment, regression of all intracranial and spinal tumors was observed, along with corresponding increases in levels of cytokines and immune cells in the cerebrospinal fluid. This clinical response continued for 7.5 months after the initiation of CAR T-cell therapy. (Funded by Gateway for Cancer Research and others; ClinicalTrials.gov number, NCT02208362 .).


Assuntos
Linfócitos T CD8-Positivos/imunologia , Glioblastoma/terapia , Imunoterapia Adotiva , Recidiva Local de Neoplasia/terapia , Receptores de Antígenos de Linfócitos T/uso terapêutico , Engenharia Celular , Terapia Combinada , Humanos , Subunidade alfa2 de Receptor de Interleucina-13 , Masculino , Pessoa de Meia-Idade
20.
Mol Ther ; 26(1): 31-44, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29103912

RESUMO

T cell immunotherapy is emerging as a powerful strategy to treat cancer and may improve outcomes for patients with glioblastoma (GBM). We have developed a chimeric antigen receptor (CAR) T cell immunotherapy targeting IL-13 receptor α2 (IL13Rα2) for the treatment of GBM. Here, we describe the optimization of IL13Rα2-targeted CAR T cells, including the design of a 4-1BB (CD137) co-stimulatory CAR (IL13BBζ) and a manufacturing platform using enriched central memory T cells. Utilizing orthotopic human GBM models with patient-derived tumor sphere lines in NSG mice, we found that IL13BBζ-CAR T cells improved anti-tumor activity and T cell persistence as compared to first-generation IL13ζ-CAR CD8+ T cells that had shown evidence for bioactivity in patients. Investigating the impact of corticosteroids, given their frequent use in the clinical management of GBM, we demonstrate that low-dose dexamethasone does not diminish CAR T cell anti-tumor activity in vivo. Furthermore, we found that local intracranial delivery of CAR T cells elicits superior anti-tumor efficacy as compared to intravenous administration, with intraventricular infusions exhibiting possible benefit over intracranial tumor infusions in a multifocal disease model. Overall, these findings help define parameters for the clinical translation of CAR T cell therapy for the treatment of brain tumors.


Assuntos
Glioblastoma/imunologia , Glioblastoma/metabolismo , Imunoterapia Adotiva , Subunidade alfa2 de Receptor de Interleucina-13/antagonistas & inibidores , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Anticorpos Antineoplásicos/imunologia , Antígenos CD19/imunologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Citotoxicidade Imunológica , Dextroanfetamina/farmacologia , Modelos Animais de Doenças , Ordem dos Genes , Engenharia Genética , Vetores Genéticos/genética , Glioblastoma/mortalidade , Glioblastoma/terapia , Humanos , Imunoterapia Adotiva/métodos , Subunidade alfa2 de Receptor de Interleucina-13/imunologia , Camundongos , Receptores de Antígenos Quiméricos/química , Ensaios Antitumorais Modelo de Xenoenxerto
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