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1.
Nano Lett ; 23(2): 476-490, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36638236

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease with multifactorial pathogenesis. However, most current therapeutic approaches for AD target a single pathophysiological mechanism, generally resulting in unsatisfactory therapeutic outcomes. Recently, mesenchymal stem cell (MSC) therapy, which targets multiple pathological mechanisms of AD, has been explored as a novel treatment. However, the low brain retention efficiency of administered MSCs limits their therapeutic efficacy. In addition, autologous MSCs from AD patients may have poor therapeutic abilities. Here, we overcome these limitations by developing iron oxide nanoparticle (IONP)-incorporated human Wharton's jelly-derived MSCs (MSC-IONPs). IONPs promote therapeutic molecule expression in MSCs. Following intracerebroventricular injection, MSC-IONPs showed a higher brain retention efficiency under magnetic guidance. This potentiates the therapeutic efficacy of MSCs in murine models of AD. Furthermore, human Wharton's jelly-derived allogeneic MSCs may exhibit higher therapeutic abilities than those of autologous MSCs in aged AD patients. This strategy may pave the way for developing MSC therapies for AD.


Assuntos
Doença de Alzheimer , Células-Tronco Mesenquimais , Doenças Neurodegenerativas , Geleia de Wharton , Humanos , Camundongos , Animais , Idoso , Doença de Alzheimer/terapia , Doença de Alzheimer/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro , Diferenciação Celular
2.
Sensors (Basel) ; 23(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37896617

RESUMO

Point-of-care testing (POCT) platforms utilizing immunoassay-based microfluidic chips offer a robust and specific method for detecting target antibodies, demonstrating a wide range of applications in various medical and research settings. Despite their versatility and specificity, the adoption of these immunoassay chips in POCT has been limited by their short shelf-life in liquid environments, attributed to the degradation of immobilized antibodies. This technical limitation presents a barrier, particularly for resource-limited settings where long-term storage and functionality are critical. To address this challenge, we introduce a novel freeze-dry sublimation process aimed at extending the shelf-life of these microfluidic chips without compromising their functional integrity. This study elaborates on the mechanisms by which freeze-drying preserves the bioactivity of the immobilized antibodies, thereby maintaining the chip's performance over an extended period. Our findings reveal significant shelf-life extension, making it possible for these POCT platforms to be more widely adopted and practically applied, especially in settings with limited resources. This research paves the way for more accessible, long-lasting, and effective POCT solutions, breaking down previous barriers to adoption and application.


Assuntos
Anticorpos Imobilizados , Microfluídica , Microfluídica/métodos , Imunoensaio/métodos , Liofilização/métodos
3.
Euro Surveill ; 27(49)2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36695442

RESUMO

The coronavirus disease (COVID-19) presented a unique opportunity for the World Health Organization (WHO) to utilise public health intelligence (PHI) for pandemic response. WHO systematically captured mainly unstructured information (e.g. media articles, listservs, community-based reporting) for public health intelligence purposes. WHO used the Epidemic Intelligence from Open Sources (EIOS) system as one of the information sources for PHI. The processes and scope for PHI were adapted as the pandemic evolved and tailored to regional response needs. During the early months of the pandemic, media monitoring complemented official case and death reporting through the International Health Regulations mechanism and triggered alerts. As the pandemic evolved, PHI activities prioritised identifying epidemiological trends to supplement the information available through indicator-based surveillance reported to WHO. The PHI scope evolved over time to include vaccine introduction, emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, unusual clinical manifestations and upsurges in cases, hospitalisation and death incidences at subnational levels. Triaging the unprecedented high volume of information challenged surveillance activities but was managed by collaborative information sharing. The evolution of PHI activities using multiple sources in WHO's response to the COVID-19 pandemic illustrates the future directions in which PHI methodologies could be developed and used.


Assuntos
COVID-19 , Saúde Pública , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias/prevenção & controle , Organização Mundial da Saúde , Inteligência
4.
Analyst ; 143(22): 5380-5387, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30280723

RESUMO

In point-of-care testing, in-line holographic microscopes paved the way for realizing portable cell counting systems at marginal cost. To maximize their accuracy, it is critically important to reliably count the number of cells even in noisy blood images overcoming various problems due to out-of-focus blurry cells and background brightness variations. However, previous studies could detect cells only on clean images while they failed to accurately distinguish blurry cells from background noises. To address this problem, we present a human-level blood cell counting system by synergistically integrating the methods of normalized cross-correlation (NCC) and a convolutional neural network (CNN). Our comprehensive performance evaluation demonstrates that the proposed system achieves the highest level of accuracy (96.7-98.4%) for any kinds of blood cells on a lens-free shadow image while others suffer from significant accuracy degradations (12.9-38.9%) when detecting blurry cells. Moreover, it outperforms others by up to 36.8% in accurately analyzing noisy blood images and is 24.0-40.8× faster, thus maximizing both accuracy and computational efficiency.


Assuntos
Contagem de Células Sanguíneas/métodos , Células Sanguíneas , Algoritmos , Animais , Holografia/métodos , Humanos , Camundongos , Microscopia/métodos , Células NIH 3T3 , Redes Neurais de Computação , Sistemas Automatizados de Assistência Junto ao Leito
5.
Sensors (Basel) ; 18(9)2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30177625

RESUMO

The digital in-line holographic microscope (DIHM) was developed for a 2D imaging technology and has recently been adapted to 3D imaging methods, providing new approaches to obtaining volumetric images with both a high resolution and wide field-of-view (FOV), which allows the physical limitations to be overcome. However, during the sectioning process of 3D image generation, the out-of-focus image of the object becomes a significant impediment to obtaining evident 3D features in the 2D sectioning plane of a thick biological sample. Based on phase retrieved high-resolution holographic imaging and a 3D deconvolution technique, we demonstrate that a high-resolution 3D volumetric image, which significantly reduces wave-front reconstruction and out-of-focus artifacts, can be achieved. The results show a 3D volumetric image that is more finely focused compared to a conventional 3D stacked image from 2D reconstructed images in relation to micron-size polystyrene beads, a whole blood smear, and a kidney tissue sample. We believe that this technology can be applicable for medical-grade images of smeared whole blood or an optically cleared tissue sample for mobile phytological microscopy and laser sectioning microscopy.

6.
Analyst ; 142(1): 110-117, 2016 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-27827471

RESUMO

In this study, we present a role of arrayed micropillar structures in cell rolling dynamics. Cell rolling on a ligand coated surface as a means of cell separation was demonstrated using a micropillar-integrated microfluidic channel. This approach allows the separation of cells according to characteristic surface properties, regardless of cell size. In these experiments, different moving trajectories of the cells between a ligand-coated micropost structure and a 1% BSA coated micropost structure were observed using sequential images. Based on the analysis of the angle of travel of cells in the trajectory, the average angles of travel on the ligand-coated microposts were 1.5° and -3.1° on a 1% BSA-coated micropost structure. The overall force equivalent applied to a cell can be analyzed to predict the cell rolling dynamics when a cell is detached. These results show that it will be possible to design chip geometry for delicate operations and to separate target cells. Furthermore, we believe that these control techniques based on a ligand coated micropillar surface can be used for enhancing cell rolling-based separation in a faster and more continuous manner.


Assuntos
Movimento Celular , Técnicas Citológicas/instrumentação , Dispositivos Lab-On-A-Chip , Separação Celular , Células HL-60 , Humanos , Cinética , Ligantes , Selectina-P/metabolismo , Propriedades de Superfície
7.
Biomed Microdevices ; 17(4): 70, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26112614

RESUMO

Applications of microfluidic devices fabricated in poly(dimethylsiloxane) (PDMS) have been limited to water-based analysis rather than nonpolar solvent based chemistry due to a PDMS swelling problem that occurs by the absorption of the solvents. The absorption and swelling causes PDMS channel deformation in shape, and changes the cross sectional area making it difficult to control the flow rate and concentrations of solution in PDMS microfluidic channels. We propose that poly-p-xylylene polymers (parylenes) are chemical vapors deposited on the surfaces of PDMS channels that alleviate the effect of solvents on the absorption and swelling. The parylene coated surface sustains 3 h with a small volumetric change (less than 22 % of PDMS swelling ratio). By generating an air-nonpolar solvent interface based on droplets in PDMS channel, we confirmed poly-p-xylylene coated PDMS microfluidic channels have the potential to be applicable to nanocrystal growth using nonpolar solvents.


Assuntos
Dimetilpolisiloxanos/química , Microfluídica , Nanopartículas/química , Solventes/química , Desenho de Equipamento , Técnicas Analíticas Microfluídicas/instrumentação , Polímeros/química , Silicones/química , Propriedades de Superfície , Xilenos/química
8.
Analyst ; 140(21): 7373-81, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26381726

RESUMO

Fluorescence cell imaging using a fluorescence microscope is an extensively used technique to examine the cell nucleus, internal structures, and other cellular molecules with fluorescence response time and intensity. However, it is difficult to perform high resolution cell imaging for a long period of time with this technique due to necrosis and apoptosis depending on the type and subcellular location of the damage caused by phototoxicity. A large number of studies have been performed to resolve this problem, but researchers have struggled to meet the challenge between cellular viability and image resolution. In this study, we employ a specially designed disc to reduce cell damage by controlling total fluorescence exposure time without deterioration of the image resolution. This approach has many advantages such as, the apparatus is simple, cost-effective, and easily integrated into the optical pathway through a conventional fluorescence microscope.


Assuntos
Microscopia de Fluorescência/métodos , Apoptose , Contagem de Células , Núcleo Celular/metabolismo , Sobrevivência Celular , Análise Custo-Benefício , Desenho de Equipamento , Fluorescência , Corantes Fluorescentes/química , Células HeLa , Humanos , Necrose , Raios Ultravioleta
9.
Sensors (Basel) ; 14(8): 15244-61, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25195851

RESUMO

In a point-of-care (POC) setting, it is critically important to reliably count the number of specific cells in a blood sample. Software-based cell counting, which is far faster than manual counting, while much cheaper than hardware-based counting, has emerged as an attractive solution potentially applicable to mobile POC testing. However, the existing software-based algorithm based on the normalized cross-correlation (NCC) method is too time- and, thus, energy-consuming to be deployed for battery-powered mobile POC testing platforms. In this paper, we identify inefficiencies in the NCC-based algorithm and propose two synergistic optimization techniques that can considerably reduce the runtime and, thus, energy consumption of the original algorithm with negligible impact on counting accuracy. We demonstrate that an AndroidTM smart phone running the optimized algorithm consumes 11.5× less runtime than the original algorithm.


Assuntos
Contagem de Células/métodos , Telefone Celular , Algoritmos , Humanos , Software
10.
Adv Mater ; 36(44): e2410340, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39252658

RESUMO

T cells and macrophages have the potential to collaborate to eliminate tumor cells efficiently. Macrophages can eliminate tumor cells through phagocytosis and subsequently activate T cells by presenting tumor antigens. The activated T cells, in turn, can kill tumor cells and redirect tumor-associated macrophages toward an antitumoral M1 phenotype. However, checkpoint molecules expressed on tumor cells impede the collaborative action of these immune cells. Meanwhile, monotherapy with a single immune checkpoint inhibitor (ICI) for either macrophages or T cells yields suboptimal efficacy in cancer patients. To address this challenge, here a nanoparticle capable of efficiently delivering dual ICIs to tumors for both macrophages and T cells is developed. These programmed cell death protein 1 (PD-1)-transfected macrophage membrane-derived nanoparticles (PMMNPs) can target tumors and provide signal-regulatory protein alpha and PD-1 to block CD47 and programmed cell death-ligand 1 (PD-L1), respectively, on tumor cells. PMMNPs enhance macrophage-mediated cancer cell phagocytosis and antigen presentation, promote T cell activation, and induce the reprogramming of macrophages toward an antitumoral phenotype. In syngeneic tumor-bearing mice, PMMNPs demonstrate superior therapeutic efficacy compared to nanoparticles delivering single ICIs and non-targeted delivery of anti-CD47 and anti-PD-L1 antibodies. PMMNPs capable of augmenting the antitumoral interplay between macrophages and T cells may offer a promising avenue for cancer immunotherapy.


Assuntos
Macrófagos , Nanopartículas , Linfócitos T , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Camundongos , Nanopartículas/química , Linfócitos T/imunologia , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Antígeno B7-H1/metabolismo , Antígeno CD47/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Fagocitose/efeitos dos fármacos , Imunoterapia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/química , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/imunologia
11.
Nat Commun ; 15(1): 8481, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353987

RESUMO

Neutrophils are critical mediators of both the initiation and resolution of inflammation after myocardial infarction (MI). Overexuberant neutrophil signaling after MI exacerbates cardiomyocyte apoptosis and cardiac remodeling while neutrophil apoptosis at the injury site promotes macrophage polarization toward a pro-resolving phenotype. Here, we describe a nanoparticle that provides spatiotemporal control over neutrophil fate to both stymie MI pathogenesis and promote healing. Intravenous injection of roscovitine/catalase-loaded poly(lactic-co-glycolic acid) nanoparticles after MI leads to nanoparticle uptake by circulating neutrophils migrating to the infarcted heart. Activated neutrophils at the infarcted heart generate reactive oxygen species, triggering intracellular release of roscovitine, a cyclin-dependent kinase inhibitor, from the nanoparticles, thereby inducing neutrophil apoptosis. Timely apoptosis of activated neutrophils at the infarcted heart limits neutrophil-driven inflammation, promotes macrophage polarization toward a pro-resolving phenotype, and preserves heart function. Modulating neutrophil fate to tune both inflammatory and reparatory processes may be an effective strategy to treat MI.


Assuntos
Apoptose , Inflamação , Macrófagos , Infarto do Miocárdio , Nanopartículas , Neutrófilos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Roscovitina , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/tratamento farmacológico , Animais , Neutrófilos/imunologia , Neutrófilos/metabolismo , Inflamação/patologia , Nanopartículas/química , Apoptose/efeitos dos fármacos , Roscovitina/farmacologia , Macrófagos/imunologia , Macrófagos/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Masculino , Ácido Poliglicólico/química , Ácido Láctico/metabolismo , Modelos Animais de Doenças , Humanos
12.
Micromachines (Basel) ; 14(10)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37893337

RESUMO

Millimeter-scale biopsy tools combined with an endoscope instrument have been widely used for minimal invasive surgery and medical diagnosis. Recently, a capsule-type endoscope was developed, which requires micromachining to fabricate micro-scale biopsy tools that have a sharp tip and other complex features, e.g., nanometer-scale end-tip sharpness and a complex scalpel design. However, conventional machining approaches are not cost-effective for mass production and cannot fabricate the micrometer-scale features needed for biopsy tools. Here, we demonstrate an electroplated nickel micro-biopsy tool which features a planar shape and is suitable to be equipped with a capsule-type endoscope. Planar-type micro-biopsy tools are designed, fabricated, and evaluated through in vitro tissue dissection experiments. Various micro-biopsy tools with a long shaft and sharp tip can be easily fabricated using a thick photoresist (SU8) mold via a simple one-step lithography and nickel electroplating process. The characteristics of various micro-biopsy tool design features, including a tip taper angle, different tool geometries, and a cutting scalpel, are evaluated for efficient tissue extraction from mice intestine. These fabricated biopsy tools have shown appropriate strength and sharpness with a sufficient amount of tissue extraction for clinical applications, e.g., cancer tissue biopsy. These micro-scale biopsy tools could be easily integrated with a capsule-type endoscope and conventional forceps.

13.
Tissue Eng Regen Med ; 20(3): 389-409, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36920675

RESUMO

Various immune cells participate in repair and regeneration following tissue injury or damage, orchestrating tissue inflammation and regeneration processes. A deeper understanding of the immune system's involvement in tissue repair and regeneration is critical for the development of successful reparatory and regenerative strategies. Here we review recent technologies that facilitate cell-based and biomaterial-based modulation of the immune systems for tissue repair and regeneration. First, we summarize the roles of various types of immune cells in tissue repair. Second, we review the principle, examples, and limitations of regulatory T (Treg) cell-based therapy, a representative cell-based immunotherapy. Finally, we discuss biomaterial-based immunotherapy strategies that aim to modulate immune cells using various biomaterials for tissue repair and regeneration.


Assuntos
Imunidade , Regeneração , Materiais Biocompatíveis , Imunomodulação
14.
Bioengineering (Basel) ; 10(9)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37760194

RESUMO

This study focuses on developing and characterizing a novel 3-dimensional cell-laden micro-patterned porous structure from a mechanical engineering perspective. Tissue engineering holds great promise for repairing damaged organs but faces challenges related to cell viability, biocompatibility, and mechanical strength. This research aims to overcome these limitations by utilizing gelatin methacrylate hydrogel as a scaffold material and employing a photolithography technique for precise patterned fabrication. The mechanical properties of the structure are of particular interest in this study. We evaluate its ability to withstand external forces through compression tests, which provide insights into its strength and stability. Additionally, structural integrity is assessed over time to determine its performance in in vitro and potential in vivo environments. We investigate cell viability and proliferation within the micro-patterned porous structure to evaluate the biological aspects. MTT assays and immunofluorescence staining are employed to analyze the metabolic activity and distribution pattern of cells, respectively. These assessments help us understand the effectiveness of the structure in supporting cell growth and tissue regeneration. The findings of this research contribute to the field of tissue engineering and provide valuable insights for mechanical engineers working on developing scaffolds and structures for regenerative medicine. By addressing challenges related to cell viability, biocompatibility, and mechanical strength, we move closer to realizing clinically viable tissue engineering solutions. The novel micro-patterned porous structure holds promise for applications in artificial organ development and lays the foundation for future advancements in large soft tissue construction.

15.
Adv Mater ; 35(49): e2303979, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37515819

RESUMO

Conventional approaches to developing therapeutic cancer vaccines that primarily activate tumor-specific T cells via dendritic cells (DCs) often demonstrate limited efficacy due to the suboptimal activation of these T cells. To address this limitation, here a therapeutic cancer nanovaccine is developed that enhances T cell responses by interacting with both DCs and T cells. The nanovaccine is based on a cancer cell membrane nanoparticle (CCM-MPLA) that utilizes monophosphoryl lipid A (MPLA) as an adjuvant. To allow direct interaction between the nanovaccine and tumor-specific T cells, anti-CD28 antibodies (aCD28) are conjugated onto CCM-MPLA, resulting in CCM-MPLA-aCD28. This nanovaccine activates tumor-specific CD8+ T cells in both the presence and absence of DCs. Compared with nanovaccines that interact with either DCs (CCM-MPLA) or T cells (CCM-aCD28), CCM-MPLA-aCD28 induces more potent responses of tumor-specific CD8+ T cells and exhibits a higher antitumor efficacy in tumor-bearing mice. No differences in T cell activation efficiency and therapeutic efficacy are observed between CCM-MPLA and CCM-aCD28. This approach may lead to the development of effective personalized therapeutic cancer vaccines prepared from autologous cancer cells.


Assuntos
Vacinas Anticâncer , Neoplasias , Animais , Camundongos , Linfócitos T CD8-Positivos , Vacinas Anticâncer/uso terapêutico , Células Dendríticas , Neoplasias/patologia , Imunoterapia/métodos
16.
Exp Mol Med ; 55(3): 541-554, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36854774

RESUMO

The development of therapeutic cancer vaccines (TCVs) that provide clinical benefits is challenging mainly due to difficulties in identifying immunogenic tumor antigens and effectively inducing antitumor immunity. Furthermore, there is an urgent need for personalized TCVs because only a limited number of tumor antigens are shared among cancer patients. Several autologous nanovaccines that do not require the identification of immunogenic tumor antigens have been proposed as personalized TCVs. However, these nanovaccines generally require exogenous adjuvants (e.g., Toll-like receptor agonists) to improve vaccine immunogenicity, which raises safety concerns. Here, we present senescent cancer cell-derived nanovesicle (SCCNV) as a personalized TCV that provides patient-specific tumor antigens and improved vaccine immunogenicity without the use of exogenous adjuvants. SCCNVs are prepared by inducing senescence in cancer cells ex vivo and subsequently extruding the senescent cancer cells through nanoporous membranes. In the clinical setting, SCCNVs can be prepared from autologous cancer cells from the blood of liquid tumor patients or from tumors surgically removed from solid cancer patients. SCCNVs also contain interferon-γ and tumor necrosis factor-α, which are expressed during senescence. These endogenous cytokines act as adjuvants and enhance vaccine immunogenicity, avoiding the need for exogenous adjuvants. Intradermally injected SCCNVs effectively activate dendritic cells and tumor-specific T cells and inhibit primary and metastatic tumor growth and tumor recurrence. SCCNV therapy showed an efficacy similar to that of immune checkpoint blockade (ICB) therapy and synergized with ICB. SCCNVs, which can be prepared using a simple and facile procedure, show potential as personalized TCVs.


Assuntos
Vacinas Anticâncer , Neoplasias , Humanos , Vacinas Anticâncer/uso terapêutico , Neoplasias/tratamento farmacológico , Antígenos de Neoplasias , Adjuvantes Imunológicos
17.
Adv Mater ; 35(3): e2207719, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36329674

RESUMO

Alzheimer's disease (AD), the most common cause of dementia, is a complex condition characterized by multiple pathophysiological mechanisms including amyloid-ß (Aß) plaque accumulation and neuroinflammation in the brain. The current immunotherapy approaches, such as anti-Aß monoclonal antibody (mAb) therapy, Aß vaccines, and adoptive regulatory T (Treg) cell transfer, target a single pathophysiological mechanism, which may lead to unsatisfactory therapeutic efficacy. Furthermore, Aß vaccines often induce T helper 1 (Th1) cell-mediated inflammatory responses. Here, a nanovaccine composed of lipid nanoparticles loaded with Aß peptides and rapamycin is developed, which targets multiple pathophysiological mechanisms, exhibits the combined effects of anti-Aß antibody therapy and adoptive Aß-specific Treg cell transfer, and can overcome the limitations of current immunotherapy approaches for AD. The Nanovaccine effectively delivers rapamycin and Aß peptides to dendritic cells, produces both anti-Aß antibodies and Aß-specific Treg cells, removes Aß plaques in the brain, alleviates neuroinflammation, prevents Th1 cell-mediated excessive immune responses, and inhibits cognitive impairment in mice. The nanovaccine shows higher efficacy in cognitive recovery than an Aß vaccine. Unlike anti-Aß mAb therapy and adoptive Treg cell transfer, both of which require complicated and costly manufacturing processes, the nanovaccine is easy-to-prepare and cost-effective. The nanovaccines can represent a novel treatment option for AD.


Assuntos
Doença de Alzheimer , Vacinas , Camundongos , Animais , Linfócitos T Reguladores , Doenças Neuroinflamatórias , Camundongos Transgênicos , Peptídeos beta-Amiloides , Anticorpos Monoclonais , Modelos Animais de Doenças
18.
ACS Biomater Sci Eng ; 8(5): 1921-1929, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35416659

RESUMO

The vast majority of drug-eluting stents (DES) elute either sirolimus or one of its analogues. While limus drugs stymie vascular smooth muscle cell (VSMC) proliferation to prevent in-stent restenosis, their antiproliferative nature is indiscriminate and limits healing of the endothelium in stented vessels, increasing the risk of late-stent thrombosis. Oxidative stress, which is associated with vascular injury from stent implantation, can induce VSMCs to undergo senescence, and senescent VSMCs can produce pro-inflammatory cytokines capable of inducing proliferation of neighboring nonsenescent VSMCs. We explored the potential of senolytic therapy, which involves the selective elimination of senescent cells, in the form of a senolytic-eluting stent (SES) for interventional cardiology. Oxidative stress was modeled in vitro by exposing VSMCs to H2O2, and H2O2-mediated senescence was evaluated by cytochemical staining of senescence-associated ß-galactosidase activity and qRT-PCR. Quiescent VSMCs were then treated with the conditioned medium (CM) of H2O2-treated VSMCs. Proliferative effects of CM were analyzed by staining for proliferating cell nuclear antigen. Senolytic effects of the first-generation senolytic ABT263 were observed in vitro, and the effects of ABT263 on endothelial cells were also investigated through an in vitro re-endothelialization assay. SESs were prepared by dip coating. Iliofemoral arteries of hypercholesteremic rabbits were implanted with SES, everolimus-eluting stents (EESs), or bare-metal stents (BMSs), and the area of stenosis was measured 4 weeks post-implantation using optical coherence tomography. We found that a portion of H2O2-treated VSMCs underwent senescence, and that CM of H2O2-treated senescent VSMCs triggered the proliferation of quiescent VSMCs. ABT263 reverted H2O2-mediated senescence and the proliferative capacity of senescent VSMC CM. Unlike everolimus, ABT263 did not affect endothelial cell migration and/or proliferation. SES, but not EES, significantly reduced stenosis area in vivo compared with bare-metal stents (BMSs). This study shows the potential of SES as an alternative to current forms of DES.


Assuntos
Reestenose Coronária , Stents Farmacológicos , Animais , Constrição Patológica , Reestenose Coronária/prevenção & controle , Stents Farmacológicos/efeitos adversos , Células Endoteliais , Everolimo/farmacologia , Peróxido de Hidrogênio/farmacologia , Coelhos , Senoterapia , Stents
19.
Tissue Eng Regen Med ; 18(5): 807-818, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34251653

RESUMO

BACKGROUND: Various cell-culture systems have been used to evaluate drug toxicity in vitro. However, factors that affect cytotoxicity outcomes in drug toxicity evaluation systems remain elusive. In this study, we used multilayered sheets of cardiac-mimetic cells, which were reprogrammed from human fibroblasts, to investigate the effects of the layer number on drug cytotoxicity outcomes. METHODS: Cell sheets of cardiac-mimetic cells were fabricated by reprogramming of human fibroblasts into cardiac-mimetic cells via coculture with cardiac cells and electric stimulation, as previously described. Double-layered cell sheets were prepared by stacking the cell sheets. The mono- and double-layered cell sheets were treated with 5-fluorouracil (5-FU), an anticancer drug, in vitro. Subsequently, apoptosis and lipid peroxidation were analyzed. Furthermore, effects of cardiac-mimetic cell density on cytotoxicity outcomes were evaluated by culturing cells in monolayer at various cell densities. RESULTS: The double-layered cell sheets exhibited lower cytotoxicity in terms of apoptosis and lipid peroxidation than the mono-layered sheets at the same 5-FU dose. In addition, the double-layered cell sheets showed better preservation of mitochondrial function and plasma membrane integrity than the monolayer sheets. The lower cytotoxicity outcomes in the double-layered cell sheets may be due to the higher intercellular interactions, as the cytotoxicity of 5-FU decreased with cell density in monolayer cultures of cardiac-mimetic cells. CONCLUSION: The layer number of cardiac-mimetic cell sheets affects drug cytotoxicity outcomes in drug toxicity tests. The in vitro cellular configuration that more closely mimics the in vivo configuration in the evaluation systems seems to exhibit lower cytotoxicity in response to drug.


Assuntos
Coração , Preparações Farmacêuticas , Células Cultivadas , Técnicas de Cocultura , Fibroblastos , Humanos
20.
Adv Mater ; 33(43): e2103258, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34510559

RESUMO

Chimeric antigen receptor-T (CAR-T) cell immunotherapy has shown impressive clinical outcomes for hematologic malignancies. However, its broader applications are challenged due to its complex ex vivo cell-manufacturing procedures and low therapeutic efficacy against solid tumors. The limited therapeutic effects are partially due to limited CAR-T cell infiltration to solid tumors and inactivation of CAR-T cells by the immunosuppressive tumor microenvironment. Here, a facile approach is presented to in vivo program macrophages, which can intrinsically penetrate solid tumors, into CAR-M1 macrophages displaying enhanced cancer-directed phagocytosis and anti-tumor activity. In vivo injected nanocomplexes of macrophage-targeting nanocarriers and CAR-interferon-γ-encoding plasmid DNA induce CAR-M1 macrophages that are capable of CAR-mediated cancer phagocytosis, anti-tumor immunomodulation, and inhibition of solid tumor growth. Together, this study describes an off-the-shelf CAR-macrophage therapy that is effective for solid tumors and avoids the complex and costly processes of ex vivo CAR-cell manufacturing.


Assuntos
Receptores de Antígenos Quiméricos
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