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1.
J Endod ; 50(7): 1004-1010, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38631475

RESUMO

INTRODUCTION: This ex vivo study evaluated the accuracy of the Electronic Apex Locator (EAL) and Automatic Apical Stop (AAS) functions of the E-Connect S+ and Morita Tri Auto ZX2+ cordless apex locators in determining patency length. METHODS: Sixty-four human teeth with a single root were randomly allocated into E-connect or Morita groups (n = 32). The canals were accessed and preflared, after which a size 15 K-file was inserted into the canal to the major foramen and recorded as the actual length (AL). Matched measurements were taken using the AAS and EAL functions and visually confirmed with confocal microscopy. The variance between canal length (mm), the persons correlation (ρ) between function and AL, and the accuracy (%) of the canal length relative to the AL (Δmm) between devices and functions were assessed. RESULTS: Regardless of device or function, all measurements were within 1±Δmm and correlated strongly (ρ > 0.97) with the AL. When considering a more stringent clinically acceptable range of 0.5±Δmm from the AL, all devices and functions demonstrated similar accuracy levels (84%-94%). However, at lower tolerance ranges, the E-connect device with the EAL function exhibited the highest accuracy. On average, all devices and functions stopped short of the AL (mean Δmm>0). CONCLUSION: The E-Connect S+ and Morita Tri Auto ZX2+ apex locators provided reliable accuracy in determining the position of the major foramen. These findings demonstrate a high level of reproducibility in canal length measurements using both cordless endodontic handpieces, regardless of whether the EAL or AAS functions were employed.


Assuntos
Cavidade Pulpar , Odontometria , Humanos , Cavidade Pulpar/anatomia & histologia , Odontometria/métodos , Ápice Dentário/anatomia & histologia , Preparo de Canal Radicular/instrumentação , Instrumentos Odontológicos
2.
MAbs ; 15(1): 2261509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37823690

RESUMO

There are few treatments that slow neurodegeneration in Alzheimer's disease (AD), and while therapeutic antibodies are being investigated in clinical trials for AD treatment, their access to the central nervous system is restricted by the blood-brain barrier. This study investigates a bispecific modular fusion protein composed of gantenerumab, a fully human monoclonal anti- amyloid-beta (Aß) antibody under investigation for AD treatment, with a human transferrin receptor 1-directed Brainshuttle™ module (trontinemab; RG6102, INN trontinemab). In vitro, trontinemab showed a similar binding affinity to fibrillar Aß40 and Aß plaques in human AD brain sections to gantenerumab. A single intravenous administration of trontinemab (10 mg/kg) or gantenerumab (20 mg/kg) to non-human primates (NHPs, Macaca fascicularis), was well tolerated in both groups. Immunohistochemistry indicated increased trontinemab uptake into the brain endothelial cell layer and parenchyma, and more homogeneous distribution, compared with gantenerumab. Brain and plasma pharmacokinetic (PK) parameters for trontinemab were estimated by nonlinear mixed-effects modeling with correction for tissue residual blood, indicating a 4-18-fold increase in brain exposure. A previously developed clinical PK/pharmacodynamic model of gantenerumab was adapted to include a brain compartment as a driver of plaque removal and linked to the allometrically scaled above model from NHP. The new brain exposure-based model was used to predict trontinemab dosing regimens for effective amyloid reduction. Simulations from these models were used to inform dosing of trontinemab in the first-in-human clinical trial.


Assuntos
Doença de Alzheimer , Anticorpos Monoclonais , Animais , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/imunologia , Peptídeos beta-Amiloides/uso terapêutico , Anticorpos Monoclonais/farmacologia , Encéfalo/metabolismo , Primatas/metabolismo
3.
Cell Mol Neurobiol ; 43(8): 4173-4187, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37698826

RESUMO

Delivering biologics to elicit a therapeutic response in the central nervous system (CNS) remains challenging due to the presence of the blood-brain barrier (BBB). Receptor-mediated transcytosis is a strategy to improve brain exposure after systemic drug administration. The availability of a clinically relevant in vitro BBB model is crucial to investigate transcytosis pathways and to predict the penetration of biologics into the CNS. We created a perfused human in vitro BBB model made of induced pluripotent stem cells (iPSC)-derived brain microvascular endothelial cells (BMEC) for studying transferrin receptor-mediated transcytosis. iPSC-derived BMEC were seeded in the top channel of a three-lane microfluidic device (OrganoPlate®). After 2 days in culture, the established cell model exhibited relevant BBB features, including physiological transendothelial electrical resistance in a transwell setting (1500 Ω*cm2), reduced apparent permeability (Papp) to the fluorescence tracer Lucifer yellow (20-fold less than cell-free chips), expression of key BBB markers such as tight junctions proteins, transporters, receptors and functional P-gp efflux pump. Moreover, the model exhibited functional transferrin receptor-mediated uptake and transcytosis. To assess selective transferrin receptor-mediated transcytosis, a mixture of anti-human transferrin receptor (MEM-189) and control (sheep IgG anti-bovine serum albumin) antibodies was perfused in the top channel for 2 h. The Papp of MEM-189 was 11-fold higher than that of the control antibody, demonstrating facilitated receptor-mediated transcytosis. Compared to published work reporting a 2-fold ratio, this result is remarkable and establishes the suitability of our model for exploring receptor-mediated transcytosis and screening of antibodies for putative brain shuttle application. A perfused in vitro human model made of iPSC-derived BMEC with the chief characteristics (barrier tightness, functionality) of the human BBB can be applied to study transferrin receptor (TfR)-mediated transcytosis of therapeutic antibodies. This may bring critical advances in drug shuttle technology. Graphical abstract generated with biorender.com.


Assuntos
Produtos Biológicos , Células-Tronco Pluripotentes Induzidas , Humanos , Anticorpos/farmacologia , Produtos Biológicos/metabolismo , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Receptores da Transferrina/metabolismo , Transcitose/fisiologia
4.
Pediatr Cardiol ; 44(7): 1629-1631, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37285040

RESUMO

Complex congenital heart defects may necessitate repeated surgical interventions throughout a patient's lifetime. Each subsequent procedure exposes patients to a greater cumulative risk, thus adding to the potential morbidity and mortality of the surgery. Transcatheter interventions can help mitigate the surgical risk for many defects and can delay or mitigate the need for surgery. This case report describes the rare use of a transapically delivered transcatheter aortic valve replacement (TAVR) therapy in a high-risk pediatric patient to postpone the need for surgery and potentially reduce the number of lifelong surgical interventions. The case highlights how transcatheter aortic valve therapies can be considered for non-standard, higher risk pediatric patients to postpone the need for surgical valve replacement and may serve as a paradigm shift in the care of complex patients with aortic valve pathology.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Persistência do Tronco Arterial , Humanos , Criança , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/etiologia , Tronco Arterial/cirurgia , Resultado do Tratamento , Valva Aórtica/cirurgia , Persistência do Tronco Arterial/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Fatores de Risco
5.
MAbs ; 14(1): 2076295, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634719

RESUMO

Cysteine-rich knob domains can be isolated from the ultralong heavy-chain complementarity-determining region (CDR) 3, which are unique to a subset of bovine antibodies, to create antibody fragments of ~4 kDa. Advantageously, the N- and C- termini of these small binding domains are in close proximity, and we propose that this may offer a practical route to engineer extrinsic binding specificity into proteins. To test this, we transplanted knob domains into various loops of rat serum albumin, targeting sites that were distal to the interface with the neonatal Fc receptor. Using knob domains raised against the clinically validated drug target complement component C5, we produced potent inhibitors, which exhibit an extended plasma half-life in vivo via attenuated renal clearance and neonatal Fc receptor-mediated avoidance of lysosomal catabolism. The same approach was also used to modify a Camelid VHH, targeting a framework loop situated at the opposing end of the domain to the CDRs, to produce a small, single-chain bispecific antibody and a dual inhibitor of Complement C3 and C5. This study presents new protein inhibitors of the complement cascade and demonstrates a broadly applicable method to engineer target specificity within polypeptide chains, using bovine knob domains.


Assuntos
Anticorpos Biespecíficos , Regiões Determinantes de Complementaridade , Animais , Anticorpos Biespecíficos/química , Bovinos , Ativação do Complemento , Regiões Determinantes de Complementaridade/química , Domínios Proteicos , Ratos
6.
Case Rep Oncol Med ; 2022: 7295305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251725

RESUMO

Checkpoint inhibitors (CPIs) and pegfilgrastim, a long-acting growth factor agent, are vital components of current cancer treatments. Immune-related adverse events (irAEs) such as colitis and pneumonitis are well-established toxicities associated with CPI therapy. However, large-vessel vasculitis secondary to CPI utilization is reported only in rare case reports and case series. Interestingly, large-vessel vasculitis has also been reported as a rare complication of pegfilgrastim use. We present a 59-year-old female with left stage IIA (cT2N0M0) triple-negative breast cancer receiving neoadjuvant decitabine and pembrolizumab prior to neoadjuvant chemotherapy (NAC). NAC included standard-of-care dose dense doxorubicin and cyclophosphamide (ddAC) supported with pegfilgrastim use followed by weekly carboplatin and paclitaxel. After receiving her second cycle of ddAC with pegfilgrastim, the patient reported five days of left shoulder and arm pain. Subsequent CT imaging demonstrated wall thickening and inflammatory changes surrounding the left subclavian artery, aortic arch, left carotid artery, proximal innominate arteries, and the mid internal carotid arteries and its branching vessels. These findings were extremely concerning for large-vessel vasculitis. Excluding CPI therapy and pegfilgrastim use, no additional inciting event or medication that the patient was exposed to was noted to be associated with large-vessel vasculitis. We present this case to report on this rare but severe complication from commonly utilized agents in cancer treatment. We also extend the possibility of large-vessel vasculitis development in relation to the COVID-19 vaccine due to shared ingredients found in both the vaccine and pegfilgrastim. It is important to outline the treatment used for such a complication as no standardized treatment has been established for large-vessel vasculitis caused by CPI therapy or pegfilgrastim use.

7.
Drug Metab Dispos ; 50(6): 837-845, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35149541

RESUMO

Therapeutic proteins (TPs) comprise a variety of modalities, including antibody-based drugs, coagulation factors, recombinant cytokines, enzymes, growth factors, and hormones. TPs usually cannot traverse cellular barriers and exert their pharmacological activity by interacting with targets on the exterior membrane of cells or with soluble ligands in the tissue interstitial fluid/blood. Due to their large size, lack of cellular permeability, variation in metabolic fate, and distinct physicochemical characteristics, TPs are subject to different absorption, distribution, metabolism, and excretion (ADME) processes as compared with small molecules. Limited regulatory guidance makes it challenging to determine the most relevant ADME data required for regulatory submissions. The TP ADME working group was sponsored by the Translational and ADME Sciences Leadership Group within the Innovation and Quality (IQ) consortium with objectives to: (1) better understand the current practices of ADME data generated for TPs across IQ member companies, (2) learn about their regulatory strategies and interaction experiences, and (3) provide recommendations on best practices for conducting ADME studies for TPs. To understand current ADME practices and regulatory strategies, an industry-wide survey was conducted within IQ member companies. In addition, ADME data submitted to the U.S. Food and Drug Administration was also collated by reviewing regulatory submission packages of TPs approved between 2011 and 2020. This article summarizes the key learnings from the survey and an overview of ADME data presented in biologics license applications along with future perspectives and recommendations for conducting ADME studies for internal decision-making as well as regulatory submissions for TPs. SIGNIFICANCE STATEMENT: This article provides comprehensive assessment of the current practices of absorption, distribution, metabolism, and excretion (ADME) data generated for therapeutic proteins (TPs) across the Innovation and Quality participating companies and the utility of the data in discovery, development, and regulatory submissions. The TP ADME working group also recommends the best practices for condu-cting ADME studies for internal decision-making and regulatory submissions.


Assuntos
Indústria Farmacêutica , Preparações Farmacêuticas/metabolismo , Estados Unidos , United States Food and Drug Administration
8.
Mil Med ; 187(5-6): e558-e561, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33580799

RESUMO

INTRODUCTION: The surge of SARS-CoV-2-virus infected (COVID-19) patients presenting to New York City (NYC) hospitals quickly overwhelmed and outnumbered the available acute care and intensive care resources in NYC in early March 2020. Upon the arrival of military medical assets to the Javits Convention Center in NYC, the planned mission to care for non-SARS-CoV-2 patients was immediately changed to manage patients with (SARS-CoV-2)COVID-19 and their comorbid conditions.Healthcare professionals from every branch of the uniformed services, augmented by state and local resources, staffed the Javits New York Medical Station (JNYMS) from April 2020. METHODS: The data review reported aggregated summary statistics and participant observations collected by N.Y. State and U.S. military officials. RESULTS: During the 28 days of patient intake at the JNYMS, 1,095 SARS-CoV-2-positive patients were transferred from NYC hospitals to the JNYMS. At its peak, the JNYMS accepted 119 patients in a single day, had a maximum census of 453, and had a peak intensive care unit census of 35. The median length of stay was 4.6 days (interquartile range: 3.1-6.9 days). A total of 103 patients were transferred back to local hospitals, and there were 6 deaths, with an overall mortality rate of 0.6% (95% CI, 0.3-1.2). DISCUSSION AND CONCLUSIONS: This is the first report of the care provided at the JNYMS. Within 2 weeks, this multi-agency effort was able to mobilize to care for over 1,000 SARS-CoV-2 patients with varying degrees of illness in a 1-month period. This was the largest field hospital mobilization in the U.S. medical history in response to a non-wartime pandemic. Its success with huge patient throughput including disposition and low mortality relieved critical overcrowding and supply deficiencies throughout NYC hospitals. The downstream impact likely saved additional hundreds of lives and reduced stress on the system during this healthcare crisis.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Humanos , Unidades Móveis de Saúde , Cidade de Nova Iorque/epidemiologia , Pandemias
9.
Data Sci J ; 202021.
Artigo em Inglês | MEDLINE | ID: mdl-34795758

RESUMO

As a result of a number of national initiatives, we are seeing rapid growth in the data important to materials science that are available over the web. Consequently, it is becoming increasingly difficult for researchers to learn what data are available and how to access them. To address this problem, the Research Data Alliance (RDA) Working Group for International Materials Science Registries (IMRR) was established to bring together materials science and information technology experts to develop an international federation of registries that can be used for global discovery of data resources for materials science. A resource registry collects high-level metadata descriptions of resources such as data repositories, archives, websites, and services that are useful for data-driven research. By making the collection searchable, it aids scientists in industry, universities, and government laboratories to discover data relevant to their research and work interests. We present the results of our successful piloting of a registry federation for materials science data discovery. In particular, we out a blueprint for creating such a federation that is capable of amassing a global view of all available materials science data, and we enumerate the requirements for the standards that make the registries interoperable within the federation. These standards include a protocol for exchanging resource descriptions and a standard metadata schema for encoding those descriptions. We summarize how we leveraged an existing standard (OAI-PMH) for metadata exchange. Finally, we review the registry software developed to realize the federation and describe the user experience.

10.
ACS Chem Biol ; 16(9): 1757-1769, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34406751

RESUMO

Cysteine-rich knob domains found in the ultralong complementarity determining regions of a subset of bovine antibodies are capable of functioning autonomously as 3-6 kDa peptides. While they can be expressed recombinantly in cellular systems, in this paper we show that knob domains are also readily amenable to a chemical synthesis, with a co-crystal structure of a chemically synthesized knob domain in complex with an antigen showing structural equivalence to the biological product. For drug discovery, following the immunization of cattle, knob domain peptides can be synthesized directly from antibody sequence data, combining the power and diversity of the bovine immune repertoire with the ability to rapidly incorporate nonbiological modifications. We demonstrate that, through rational design with non-natural amino acids, a paratope diversity can be massively expanded, in this case improving the efficacy of an allosteric peptide. As a potential route to further improve stability, we also performed head-to-tail cyclizations, exploiting the proximity of the N and C termini to synthesize functional, fully cyclic antibody fragments. Lastly, we highlight the stability of knob domains in plasma and, through pharmacokinetic studies, use palmitoylation as a route to extend the plasma half-life of knob domains in vivo. This study presents an antibody-derived medicinal chemistry platform, with protocols for solid-phase synthesis of knob domains, together with the characterization of their molecular structures, in vitro pharmacology, and pharmacokinetics.


Assuntos
Regiões Determinantes de Complementaridade/química , Fragmentos de Imunoglobulinas/química , Peptídeos Cíclicos/síntese química , Sequência de Aminoácidos , Animais , Bovinos , Fragmentos de Imunoglobulinas/sangue , Fragmentos de Imunoglobulinas/farmacologia , Masculino , Modelos Moleculares , Peptídeos Cíclicos/sangue , Peptídeos Cíclicos/farmacocinética , Ligação Proteica , Domínios Proteicos , Dobramento de Proteína , Ratos Sprague-Dawley , Técnicas de Síntese em Fase Sólida , Espectrometria de Massas em Tandem , Termodinâmica
11.
J Investig Med High Impact Case Rep ; 9: 23247096211001636, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33749363

RESUMO

Right atrial (RA) masses are rare, challenging to diagnose, and potentially life-threatening with high mortality if untreated. We present a patient presenting with diffuse large B-cell lymphoma in the brain that was incidentally found to have a large RA mass. For a better definition of the RA mass, extensive workup using multimodality imaging including chest computed tomography, transthoracic echocardiography, transesophageal echocardiography, cardiac magnetic resonance imaging, and left heart catheterization was warranted. The imaging demonstrated a large RA mass extending through the tricuspid valve into the right ventricle and superior and inferior vena cava without a mobile component. The mass was then successfully resected, and further histology examination was performed to rule out lymphoma and rare subtypes of diffuse large B-cell lymphoma. The comprehensive workup proved the RA mass to be a calcified thrombus rather than a direct metastatic spread of lymphoma.


Assuntos
Achados Incidentais , Trombose , Ecocardiografia Transesofagiana , Átrios do Coração/diagnóstico por imagem , Humanos , Trombose/diagnóstico por imagem , Trombose/etiologia , Veia Cava Inferior/diagnóstico por imagem
13.
Xenobiotica ; 51(1): 122-125, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32048540

RESUMO

1. Challenges and opportunities within peptide ADME (absorption, distribution, metabolism and elimination) were presented and discussed at the 1st peptide workshop of the Peptide ADME Discussion Group in Gothenburg, Sweden (15th of October 2018). This article summarises the presentations and discussions from this 1st workshop. The following topics were covered: Background science presentation on peptidases Presentation of various peptide ADME packages Peptide drug-drug interactions (DDI).


Assuntos
Descoberta de Drogas , Peptídeos , Simulação por Computador , Interações Medicamentosas , Humanos , Modelos Biológicos
14.
ACS Appl Mater Interfaces ; 12(3): 3815-3826, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31880423

RESUMO

A simple method to produce record concentrations (up to 10 mg mL-1) of high-quality aqueous graphene suspensions by using an ordinary benchtop magnetic stirrer is reported. The shear rates employed here are almost 10 times less than those in previous reports, and graphene is efficiently separated from unexfoliated graphite during the synthesis. Systematic optimization of synthesis parameters, such as pH, protein concentration, temperature, stirrer speed, and volume of solution, afforded efficient conversion (100%) of graphite to graphene-aqueous suspensions. The synthesis is readily scaled-up with a continuous flow reactor where the graphene is produced and separated 24/7, with little or no human intervention. Raman spectroscopy confirmed little to no sp3 or oxidative defects, and that the graphene nanosheets consisted of three to five layers. The graphene suspensions were coated on aluminum and tested for thermal conductivity applications. The thermal conductivity of our graphene sample was calculated to be 684 W m-1 K-1, a value greater than that of a commercial sample. The activation energy measured for shear exfoliation by stirring was found to be over 45 billion times smaller than the corresponding thermal activation energy, affording physical insight into the process. We hypothesize that stirring selectively populates translational states that are necessary for exfoliation and thus requires far less energy than conventional exfoliation methods, where the energy is uniformly distributed among all available modes. Therefore, an efficient, convenient, and inexpensive method for graphene production in limited-resource settings is reported here.


Assuntos
Química/métodos , Grafite/química , Soroalbumina Bovina/química , Animais , Bovinos , Oxirredução , Tamanho da Partícula , Análise Espectral Raman , Suspensões/química , Temperatura
16.
J Cardiothorac Surg ; 14(1): 61, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30876459

RESUMO

BACKGROUND: A prospective, multi-center study (RECON) was conducted to evaluate the clinical outcomes of pericardial closure using a decellularized extracellular matrix (ECM) graft derived from porcine small intestinal submucosa. METHODS: Patients indicated for open cardiac surgery with pericardial closure using ECM were eligible for the RECON study cohort. Postoperative complications and readmission of the RECON patients were compared to the patient cohort in the Nationwide Readmissions Database (NRD). Inverse probability of treatment weighting was used to control the differences in patient demographics, comorbidities, and risk factors. RESULTS: A total of 1420 patients at 42 centers were enrolled, including 923 coronary artery bypass grafting (CABG) surgeries and 436 valve surgeries. Significantly fewer valve surgery patients in the RECON cohort experienced pleural effusion (3.1% vs. 13.0%; p < 0.05) and pericardial effusion (1.5% vs. 2.6%; p < 0.05) than in the NRD cohort. CABG patients in the RECON cohort were less likely to suffer bleeding (1.2% vs. 2.9%; p < 0.05) and pericardial effusion (0.2% vs. 2.2%, p < 0.05) than those in the NRD cohort. The 30-day all-cause hospital readmission rate was significantly lower among RECON patients than NRD patients following both valve surgery (HR: 0.34; p < 0.05) and CABG surgery (HR: 0.42; p < 0.05). In the RECON study, 14.4% of CABG patients and 27.0% of valve patients had postoperative atrial fibrillation as compared to previously reported risks, which generally ranges from 20 to 30% after CABG and from 35 to 50% after valve surgery. CONCLUSIONS: Pericardial closure with ECM following cardiac surgery is associated with a reduction in the proportion of patients with pleural effusion, pericardial effusion, and 30-day readmission compared to a nationwide database. TRIAL REGISTRATION: NCT02073331 , Registered on February 27, 2014.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Matriz Extracelular/transplante , Hemorragia Pós-Operatória/etiologia , Alicerces Teciduais , Técnicas de Fechamento de Ferimentos , Idoso , Animais , Fibrilação Atrial/etiologia , Procedimentos Cirúrgicos Cardíacos/métodos , Anuloplastia da Valva Cardíaca/efeitos adversos , Ponte de Artéria Coronária/efeitos adversos , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Derrame Pericárdico/etiologia , Pericárdio/cirurgia , Derrame Pleural/etiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Suínos , Transplante Heterólogo
17.
J Autoimmun ; 95: 1-14, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30446251

RESUMO

Susceptibility to multiple autoimmune diseases is associated with common gene polymorphisms influencing IL-2 signaling and Treg function, making Treg-specific expansion by IL-2 a compelling therapeutic approach to treatment. As an in vivo IL-2 half-life enhancer we used a non-targeted, effector-function-silent human IgG1 as a fusion protein. An IL-2 mutein (N88D) with reduced binding to the intermediate affinity IL-2Rßγ receptor was engineered with a stoichiometry of two IL-2N88D molecules per IgG, i.e. IgG-(IL-2N88D)2. The reduced affinity of IgG-(IL-2N88D)2 for the IL-2Rßγ receptor resulted in a Treg-selective molecule in human whole blood pSTAT5 assays. Treatment of cynomolgus monkeys with single low doses of IgG-(IL-2N88D)2 induced sustained preferential activation of Tregs accompanied by a corresponding 10-14-fold increase in CD4+ and CD8+ CD25+FOXP3+ Tregs; conditions that had no effect on CD4+ or CD8+ memory effector T cells. The expanded cynomolgus Tregs had demethylated FOXP3 and CTLA4 epigenetic signatures characteristic of functionally suppressive cells. Humanized mice had similar selective in vivo responses; IgG-(IL-2N88D)2 increased Tregs while wild-type IgG-IL-2 increased NK cells in addition to Tregs. The expanded human Tregs had demethylated FOXP3 and CTLA4 signatures and were immunosuppressive. These results describe a next-generation immunotherapy using a long-lived and Treg-selective IL-2 that activates and expands functional Tregsin vivo. Patients should benefit from restored immune homeostasis in a personalized fashion to the extent that their autoimmune disease condition dictates opening up the possibility for remissions and cures.


Assuntos
Doenças Autoimunes/terapia , Imunoglobulina G/imunologia , Imunoterapia/métodos , Interleucina-2/imunologia , Linfotoxina-alfa/imunologia , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Sítios de Ligação , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Proliferação de Células , Metilação de DNA/efeitos dos fármacos , Modelos Animais de Doenças , Epigênese Genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/química , Imunoglobulina G/genética , Interleucina-2/administração & dosagem , Interleucina-2/química , Interleucina-2/genética , Subunidade beta de Receptor de Interleucina-2/genética , Subunidade beta de Receptor de Interleucina-2/imunologia , Ativação Linfocitária/efeitos dos fármacos , Linfotoxina-alfa/administração & dosagem , Linfotoxina-alfa/química , Linfotoxina-alfa/genética , Macaca fascicularis , Masculino , Camundongos , Camundongos Transgênicos , Modelos Moleculares , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
18.
A A Pract ; 11(5): 115-117, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29634536

RESUMO

Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a well-established alternative oxygenation method for critically ill patients. A 58-year-old male was transferred to our level 1 trauma and burn center after sustaining an inhalational injury from a carburetor explosion, with subsequent iatrogenic tracheal injury and emergent cricothyrotomy before arrival. During attempted surgical airway stabilization, our ability to ventilate and oxygenate was compromised. Intraoperative VV-ECMO enabled rescue from severe hypoxemia and subsequent recovery without lasting neurologic sequelae. This case highlights the utility of VV-ECMO for acute intraoperative rescue.


Assuntos
Queimaduras por Inalação/terapia , Oxigenação por Membrana Extracorpórea , Pneumotórax/terapia , Traqueia/lesões , Humanos , Doença Iatrogênica , Masculino , Pessoa de Meia-Idade
19.
Cell Rep ; 22(1): 149-162, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29298417

RESUMO

Receptors show promise for the transport of monoclonal antibodies (mAbs) across the blood-brain barrier. However, safety liabilities associated with peripheral receptor binding and Fc effector function have been reported. We present the Brain Shuttle-mAb (BS-mAb) technology, and we investigate the role of Fc effector function in vitro and in an Fcγ receptor (FcγR)-humanized mouse model. Strong first infusion reactions (FIRs) were observed for a conventional mAb against transferrin receptor (TfR) with a wild-type immunoglobulin G1 (IgG1) Fc. Fc effector-dead constructs completely eliminated all FIRs. Remarkably, no FIR was observed for the BS-mAb construct with a native IgG1 Fc function. Using various BS-mAb constructs, we show that TfR binding through the C-terminal BS module attenuates Fc-FcγR interactions, primarily because of steric hindrance. Nevertheless, BS-mAbs maintain effector function activity when binding their brain target. Thus, mAbs with full effector function can be transported in a stealth mode in the periphery while fully active when engaged with their brain target.


Assuntos
Doença de Alzheimer/metabolismo , Anticorpos Monoclonais , Barreira Hematoencefálica/metabolismo , Sistemas de Liberação de Medicamentos , Imunoglobulina G/farmacologia , Receptores de IgG/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Barreira Hematoencefálica/patologia , Células CHO , Cricetulus , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Receptores de IgG/genética
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