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1.
ACS Cent Sci ; 10(3): 666-675, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38559305

RESUMO

The Stimulator of Interferon Genes (STING) pathway is a promising target for cancer immunotherapy. Despite recent advances, therapies targeting the STING pathway are often limited by routes of administration, suboptimal STING activation, or off-target toxicity. Here, we report a dendritic cell (DC)-targeted polymeric prodrug platform (polySTING) that is designed to optimize intracellular delivery of a diamidobenzimidazole (diABZI) small-molecule STING agonist while minimizing off-target toxicity after parenteral administration. PolySTING incorporates mannose targeting ligands as a comonomer, which facilitates its uptake in CD206+/mannose receptor+ professional antigen-presenting cells (APCs) in the tumor microenvironment (TME). The STING agonist is conjugated through a cathepsin B-cleavable valine-alanine (VA) linker for selective intracellular drug release after receptor-mediated endocytosis. When administered intravenously in tumor-bearing mice, polySTING selectively targeted CD206+/mannose receptor+ APCs in the TME, resulting in increased cross-presenting CD8+ DCs, infiltrating CD8+ T cells in the TME as well as maturation across multiple DC subtypes in the tumor-draining lymph node (TDLN). Systemic administration of polySTING slowed tumor growth in a B16-F10 murine melanoma model as well as a 4T1 murine breast cancer model with an acceptable safety profile. Thus, we demonstrate that polySTING delivers STING agonists to professional APCs after systemic administration, generating efficacious DC-driven antitumor immunity with minimal side effects. This new polymeric prodrug platform may offer new opportunities for combining efficient targeted STING agonist delivery with other selective tumor therapeutic strategies.

2.
Cell Death Differ ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594444

RESUMO

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME). The symbiotic interactions between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAM) in the TME are critical for tumor progression. Here, we identified that IFI35, a transcriptional regulatory factor, plays both cell-intrinsic and cell-extrinsic roles in maintaining GSCs and the immunosuppressive TME. IFI35 induced non-canonical NF-kB signaling through proteasomal processing of p105 to the DNA-binding transcription factor p50, which heterodimerizes with RELB (RELB/p50), and activated cell chemotaxis in a cell-autonomous manner. Further, IFI35 induced recruitment and maintenance of M2-like TAMs in TME in a paracrine manner. Targeting IFI35 effectively suppressed in vivo tumor growth and prolonged survival of orthotopic xenograft-bearing mice. Collectively, these findings reveal the tumor-promoting functions of IFI35 and suggest that targeting IFI35 or its downstream effectors may provide effective approaches to improve GBM treatment.

3.
BME Front ; 5: 0038, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38515636

RESUMO

With the recent advances in neoantigen identification, peptide-based cancer vaccines offer substantial potential in the field of immunotherapy. However, rapid clearance, low immunogenicity, and insufficient antigen-presenting cell (APC) uptake limit the efficacy of peptide-based cancer vaccines. This review explores the barriers hindering vaccine efficiency, highlights recent advancements in synthetic delivery systems, and features strategies for the key delivery steps of lymph node (LN) drainage, APC delivery, cross-presentation strategies, and adjuvant incorporation. This paper also discusses the design of preclinical studies evaluating vaccine efficiency, including vaccine administration routes and murine tumor models.

4.
Proc Natl Acad Sci U S A ; 120(46): e2306129120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37939083

RESUMO

Controlling the biodistribution of protein- and nanoparticle-based therapeutic formulations remains challenging. In vivo library selection is an effective method for identifying constructs that exhibit desired distribution behavior; library variants can be selected based on their ability to localize to the tissue or compartment of interest despite complex physiological challenges. Here, we describe further development of an in vivo library selection platform based on self-assembling protein nanoparticles encapsulating their own mRNA genomes (synthetic nucleocapsids or synNCs). We tested two distinct libraries: a low-diversity library composed of synNC surface mutations (45 variants) and a high-diversity library composed of synNCs displaying miniproteins with binder-like properties (6.2 million variants). While we did not identify any variants from the low-diversity surface library that yielded therapeutically relevant changes in biodistribution, the high-diversity miniprotein display library yielded variants that shifted accumulation toward lungs or muscles in just two rounds of in vivo selection. Our approach should contribute to achieving specific tissue homing patterns and identifying targeting ligands for diseases of interest.


Assuntos
Biblioteca de Peptídeos , Proteínas , Distribuição Tecidual , Nucleocapsídeo , Mutação
5.
ACS Biomater Sci Eng ; 9(8): 5062-5071, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37467493

RESUMO

The manufacturing process of chimeric antigen receptor T cell therapies includes isolation systems that provide pure T cells. Current magnetic-activated cell sorting and immunoaffinity chromatography methods produce desired cells with high purity and yield but require expensive equipment and reagents and involve time-consuming incubation steps. Here, we demonstrate that aptamers can be employed in a continuous-flow resin platform for both depletion of monocytes and selection of CD8+ T cells from peripheral blood mononuclear cells at low cost with high purity and throughput. Aptamer-mediated cell selection could potentially enable fully synthetic, traceless isolations of leukocyte subsets from a single isolation system.


Assuntos
Linfócitos T CD8-Positivos , Leucócitos Mononucleares , Leucócitos , Cromatografia
6.
Chem Commun (Camb) ; 59(56): 8739-8742, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37357802

RESUMO

A binary Mo/Fe-nitrogen-carbon material (MoFe-NC) catalyst was synthesized following the concept of biological nitrogen fixation. The MoFe-NC catalyst demonstrated a maximum N2 reduction faradaic efficiency of 39.9% and a NH3 yield rate of 28.5 µg mgcat-1 h-1 under ambient conditions.

7.
J Control Release ; 356: 232-241, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36878319

RESUMO

Peptide cancer vaccines have had limited clinical success despite their safety, characterization and production advantages. We hypothesize that the poor immunogenicity of peptides can be surmounted by delivery vehicles that overcome the systemic, cellular and intracellular drug delivery barriers faced by peptides. Here, we introduce Man-VIPER, a self-assembling (40-50 nm micelles), pH-sensitive, mannosylated polymeric peptide delivery platform that targets dendritic cells in the lymph nodes, encapsulates peptide antigens at physiological pH, and facilitates endosomal release of antigens at acidic endosomal pH through a conjugated membranolytic peptide melittin. We used d-melittin to improve the safety profile of the formulation without compromising the lytic properties. We evaluated polymers with both releasable (Man-VIPER-R) or non-releasable (Man-VIPER-NR) d-melittin. Both Man-VIPER polymers exhibited superior endosomolysis and antigen cross-presentation compared to non-membranolytic d-melittin-free analogues (Man-AP) in vitro. In vivo, Man-VIPER polymers demonstrated an adjuvanting effect, induced the proliferation of antigen-specific cytotoxic T cells and helper T cells compared to free peptides and Man-AP. Remarkably, antigen delivery with Man-VIPER-NR generated significantly more antigen-specific cytotoxic T cells than Man-VIPER-R in vivo. As our candidate for a therapeutic vaccine, Man-VIPER-NR exerted superior efficacy in a B16F10-OVA tumor model. These results highlight Man-VIPER-NR as a safe and powerful peptide cancer vaccine platform for cancer immunotherapy.


Assuntos
Vacinas Anticâncer , Neoplasias , Humanos , Polímeros/química , Antígenos , Peptídeos/farmacologia , Sistemas de Liberação de Medicamentos , Apresentação de Antígeno , Neoplasias/terapia , Células Dendríticas
8.
Int Symp Med Robot ; 20222022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36129421

RESUMO

High precision is required for ophthalmic robotic systems. This paper presents the kinematic calibration for the delta robot which is part of the next generation of Steady-Hand Eye Robot (SHER). A linear error model is derived based on geometric error parameters. Two experiments with different ranges of workspace are conducted with laser sensors measuring displacement. The error parameters are identified and applied in the kinematics to compensate for modeling error. To achieve better accuracy, Bernstein polynomials are adopted to fit the error residuals after compensation. After the kinematic calibration process, the error residuals of the delta robot are reduced to satisfy the clinical requirements.

9.
Adv Healthc Mater ; 11(9): e2101651, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34706166

RESUMO

Peptide-based cancer vaccines offer production and safety advantages but have had limited clinical success due to their intrinsic instability, rapid clearance, and low cellular uptake. Nanoparticle-based delivery vehicles can improve the in vivo stability and cellular uptake of peptide antigens. Here, a well-defined, self-assembling mannosylated polymer is developed for anticancer peptide antigen delivery. The amphiphilic polymer is prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization, and the peptide antigens are conjugated to the pH-sensitive hydrophobic block through the reversible disulfide linkage for selective release after cell entry. The polymer-peptide conjugates self-assemble into sub-100 nm micelles at physiological pH and dissociate at endosomal pH. The mannosylated micellar corona increases the accumulation of vaccine cargoes in the draining inguinal lymph nodes and facilitates nanoparticle uptake by professional antigen presenting cells. In vivo studies demonstrate that the mannosylated micelle formulation improves dendritic cell activation and enhances antigen-specific T cell responses, resulting in higher antitumor immunity in tumor-bearing mice compared to free peptide antigen. The mannosylated polymer is therefore a simple and promising platform for the delivery of peptide cancer vaccines.


Assuntos
Vacinas Anticâncer , Neoplasias , Animais , Antígenos , Sistemas de Liberação de Medicamentos , Camundongos , Micelas , Neoplasias/terapia , Peptídeos , Polímeros/química , Vacinas de Subunidades
10.
Nanotechnology ; 32(50)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34479223

RESUMO

The rational design of cathode materials with core-shell heterostructures is significant to develop a Ni//Zn battery with both high gravimetric and areal energy density under high mass loading. In this work, the NiCo-OH nanothorns with a mass loading of 11.6 mg cm-2were coated on CuO nanowire arrays via a chemical bath deposition method. Thanks to the construction of 3D core-shell nanowire arrays and appropriate cobalt doping, as-fabricated Ni//Zn battery based on the NiCo-OH as cathode achieved the maximum specific capacity of 383 mAh g-1at 5 mA cm-2with high energy density of 649 Wh kg-1at 0.73 kW kg-1, indicating good energy storage performance in Ni//Zn battery.

11.
Biomaterials ; 277: 121076, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34461456

RESUMO

Melittin, the primary peptide component of bee venom, is a potent cytolytic anti-cancer peptide with established anti-tumor activity. However, practical application of melittin in oncology is hampered by its strong, nonspecific hemolytic activity and intrinsic instability. To address these shortcomings, delivery systems are used to overcome the drawbacks of melittin and facilitate its safe delivery. Yet, a recent study revealed that encapsulated melittin remains immunogenic and can act as an adjuvant to elicit a fatal antibody immune response against the delivery carrier. We discovered that substitution of l-amino acids with d-amino acids mitigates this problem: D-melittin nanoformulations induce significantly decreased immune response, resulting in excellent safety without compromising cytolytic potential. We now report the first application of D-melittin and its micellar formulations for cancer treatment. D-melittin was delivered by a pH-sensitive polymer carrier that (i) forms micellar nanoparticles at normal physiological conditions, encapsulating melittin, and (ii) dissociates at endosomal pH, restoring melittin activity. D-melittin micelles (DMM) exhibits significant cytotoxicity and induces hemolysis in a pH-dependent manner. In addition, DMM induce immunogenic cell death, revealing its potential for cancer immunotherapy. Indeed, in vivo studies demonstrated the superior safety profile of DMM over free peptide and improved efficacy at prohibiting tumor growth. Overall, we present the first application of micellar D-melittin for cancer therapy. These findings establish a new strategy for safe, systemic delivery of melittin, unlocking a potential pathway toward clinical translation for cytotoxic peptides as anti-cancer agents. which can revolutionize in vivo delivery of therapeutic peptides and peptide antigens.


Assuntos
Antineoplásicos , Nanopartículas , Antineoplásicos/uso terapêutico , Meliteno , Micelas , Polímeros
12.
Int Symp Med Robot ; 20212021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35187545

RESUMO

There has been much research exploring the use of fiber Bragg grating (FBG)-sensorized needles in the prostate biopsy procedure, but all FBG needles used in the research need to be calibrated, which is time consuming and prone to human errors. In this work, a semi-automatic robotic system was developed to perform FBG needle calibration. Compared to manual calibration results, the robotic system is able to calibrate FBG needles with the similar level of accuracy as achieved by an experienced manual operator, thus reducing the time cost during the needle calibration process.

13.
J Control Release ; 328: 834-845, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33157191

RESUMO

Adeno-associated virus (AAV) is a promising vector for gene therapy, but its broad tropism can be detrimental if the transgene being delivered is harmful when expressed ubiquitously in the body, i.e. in non-target tissues. Delivering the transgene of interest to target cells at levels high enough to be therapeutically effective while maintaining safety by minimizing delivery to off-target cells is a prevalent challenge in the field of gene therapy. We have developed a protease activatable vector (provector) platform based on AAV9 that can be injected systemically to deliver therapeutic transgenes site-specifically to diseased cells by responding to extracellular proteases present at the disease site. The provector platform consists of a peptide insertion into the virus capsid which disrupts the virus' ability to bind to cell surface receptors. This peptide contains a blocking motif (aspartic acid residues) flanked on either side by cleavage sequences that are recognized by certain proteases. Exposure to proteases cleaves the peptides off the capsid, activating or "switching ON" the provector. In response to the activation, the provectors regain their ability to bind and transduce cells. Here, we have designed a provector that is activated by cysteine aspartic proteases (caspases), which have roles in inflammation and apoptosis and thus are elevated at sites of diseases such as heart failure, neurodegenerative diseases, and ischemic stroke. This provector demonstrates a 200-fold reduction in transduction ability in the OFF state compared to AAV9, reducing the virus' ability to transduce off-target healthy tissue. Following exposure to and proteolysis by caspase-3, the provector shows a 95-fold increase in transduction compared to the OFF state. The switchable transduction behavior was found to be a direct result of the peptide insertion ablating the ability of the virus to bind to cells. In vivo studies were conducted to characterize the biodistribution, blood circulation time, neutralizing antibody formation, and targeted delivery ability of the caspase-activatable provector in a model of heart failure.


Assuntos
Dependovirus , Vetores Genéticos , Caspases , Dependovirus/genética , Técnicas de Transferência de Genes , Terapia Genética , Distribuição Tecidual , Transdução Genética , Transgenes
14.
Nanotechnology ; 31(43): 435407, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-32599569

RESUMO

Three-dimensionally mesoporous La1-xSrxFeO3 (x = 0, 0.4, 0.6) precursors have been synthesized through a facile solvothermal process. After high-temperature sintering, La1-xSrxFeO3 still exhibits uniform morphology and good dispersibility, which provides a porous structure and favorable surface area. Particularly, La0.4Sr0.6FeO3 shows the biggest surface area of 58 m2 g-1. Doping also induces the generation of oxygen vacancies and Fe4+, which is beneficial for the conductivity and catalytic activity of the materials. Complete with favorable structure and electrochemical activity, La0.4Sr0.6FeO3 exhibits bifunctional catalytic activity in alkaline solution. Applied as a cathode catalyst in Li-O2 batteries, it shows a larger discharge capacity of 23 905 mA h g-1 and a better cycling stability of 100 cycles.

15.
Nanotechnology ; 31(16): 165709, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-31899902

RESUMO

High-efficiency and low-cost electrocatalysts are generally believed to be the critical factor and have been highly researched to catalyze the oxygen reduction reaction (ORR) during the operation of Li-O2 battery (LOB). The catalysts with better ORR performance are essential for high-performance LOBs. Herein, a binder-free MnO x @carbon cloth cathode composed of Mn3O4 nanoparticles and Mn2O3 nanosheets were directly synthesized on the carbon cloth by electrodeposition and subsequently heat treatment at different temperature (from 200 °C to 400 °C). With the increase of temperature, the Mn3O4 nanospheres gradually transformed into Mn2O3 nanosheets. The MnO x obtained at 350 °C exhibited the best ORR performance. And MnO x -350 °C could operate more than 80 cycles at 340 mA g-1 with a limiting specific capacity of 1000 mAh g-1, and its first discharge specific capacity could nearly achieve 8000 mAh g-1 at 200 mA g-1.

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