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1.
Nature ; 597(7878): 660-665, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34588671

RESUMO

The densification of integrated circuits requires thermal management strategies and high thermal conductivity materials1-3. Recent innovations include the development of materials with thermal conduction anisotropy, which can remove hotspots along the fast-axis direction and provide thermal insulation along the slow axis4,5. However, most artificially engineered thermal conductors have anisotropy ratios much smaller than those seen in naturally anisotropic materials. Here we report extremely anisotropic thermal conductors based on large-area van der Waals thin films with random interlayer rotations, which produce a room-temperature thermal anisotropy ratio close to 900 in MoS2, one of the highest ever reported. This is enabled by the interlayer rotations that impede the through-plane thermal transport, while the long-range intralayer crystallinity maintains high in-plane thermal conductivity. We measure ultralow thermal conductivities in the through-plane direction for MoS2 (57 ± 3 mW m-1 K-1) and WS2 (41 ± 3 mW m-1 K-1) films, and we quantitatively explain these values using molecular dynamics simulations that reveal one-dimensional glass-like thermal transport. Conversely, the in-plane thermal conductivity in these MoS2 films is close to the single-crystal value. Covering nanofabricated gold electrodes with our anisotropic films prevents overheating of the electrodes and blocks heat from reaching the device surface. Our work establishes interlayer rotation in crystalline layered materials as a new degree of freedom for engineering-directed heat transport in solid-state systems.

2.
Mol Cell Neurosci ; 130: 103950, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901655

RESUMO

Amyloid beta (Aß) peptides, which aggregate to form neocortical plaques in Alzheimer's disease, exist in states that range from soluble monomers and oligomers/protofibrils to insoluble fibrillar amyloid. The present study evaluated the effects of mAb158, a mouse monoclonal antibody version of lecanemab that preferentially binds to soluble Aß protofibrils, in aged transgenic mice (Tg2576) with Aß pathology. Female Tg2576 mice (12 months old) received weekly intraperitoneal mAb158 (35 mg/kg) or vehicle for 4 weeks or for 18 weeks, with or without a subsequent 12-week off-treatment period. Aß protofibril levels were significantly lower in mAb158-treated animals at both 4 and 18 weeks, while longer treatment duration (18 weeks) was required to observe significantly lower Aß42 levels in insoluble brain fractions and lower Aß plaque load. Following the off-treatment period, comparison of the vehicle- and mAb158-treated mice demonstrated that the Aß protofibril levels, insoluble Aß42 levels and Aß plaque load remained significantly lower in mAb158-treated animals, as compared with age-matched controls. However, there was a significant increase of brain accumulation of both the Aß protofibril levels, insoluble Aß42 levels and Aß plaque load after treatment cessation. Thus, repeated mAb158 treatment of aged Tg2576 mice first reduced Aß protofibril levels within 4 weeks of treatment, which then was followed by a reduction of amyloid plaque pathology within 18 weeks of treatment. These effects were maintained 12 weeks after the final dose, indicating that mAb158 had a disease-modifying effect on the Aß pathology in this mouse model. In addition, brain accumulation of both Aß protofibril levels and amyloid pathology progressed after discontinuation of the treatment which supports the importance of continued treatment with mAb158 to maintain the effects on Aß pathology.

3.
Neurobiol Dis ; 161: 105543, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34737044

RESUMO

A growing body of evidence suggests that aggregated α-synuclein, the major constituent of Lewy bodies, plays a key role in the pathogenesis of Parkinson's disease and related α-synucleinopathies. Immunotherapies, both active and passive, against α-synuclein have been developed and are promising novel treatment strategies for such disorders. Here, we report on the humanization and pharmacological characteristics of ABBV-0805, a monoclonal antibody that exhibits a high selectivity for human aggregated α-synuclein and very low affinity for monomers. ABBV-0805 binds to a broad spectrum of soluble aggregated α-synuclein, including small and large aggregates of different conformations. Binding of ABBV-0805 to pathological α-synuclein was demonstrated in Lewy body-positive post mortem brains of Parkinson's disease patients. The functional potency of ABBV-0805 was demonstrated in several cellular assays, including Fcγ-receptor mediated uptake of soluble aggregated α-synuclein in microglia and inhibition of neurotoxicity in primary neurons. In vivo, the murine version of ABBV-0805 (mAb47) displayed significant dose-dependent decrease of α-synuclein aggregates in brain in several mouse models, both in prophylactic and therapeutic settings. In addition, mAb47 treatment of α-synuclein transgenic mice resulted in a significantly prolonged survival. ABBV-0805 selectively targets soluble toxic α-synuclein aggregates with a picomolar affinity and demonstrates excellent in vivo efficacy. Based on the strong preclinical findings described herein, ABBV-0805 has been progressed into clinical development as a potential disease-modifying treatment for Parkinson's disease.


Assuntos
Anticorpos Monoclonais , Doença de Parkinson , Sinucleinopatias , Animais , Anticorpos Monoclonais/uso terapêutico , Humanos , Longevidade , Camundongos , Camundongos Transgênicos , Doença de Parkinson/metabolismo , Doença de Parkinson/terapia , Sinucleinopatias/terapia , alfa-Sinucleína/metabolismo
4.
Opt Express ; 25(15): 18274-18287, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28789315

RESUMO

The influence of B4C incorporation during magnetron sputter deposition of Cr/Sc multilayers intended for soft X-ray reflective optics is investigated. Chemical analysis suggests formation of metal: boride and carbide bonds which stabilize an amorphous layer structure, resulting in smoother interfaces and an increased reflectivity. A near-normal incidence reflectivity of 11.7%, corresponding to a 67% increase, is achieved at λ = 3.11 nm upon adding 23 at.% (B + C). The advantage is significant for the multilayer periods larger than 1.8 nm, where amorphization results in smaller interface widths, for example, giving 36% reflectance and 99.89% degree of polarization near Brewster angle for a multilayer polarizer. The modulated ion-energy-assistance during the growth is considered vital to avoid intermixing during the interface formation even when B + C are added.

5.
Cell Mol Neurobiol ; 37(1): 121-131, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26961542

RESUMO

Immunotherapy targeting aggregated α-synuclein has emerged as a potential treatment strategy against Parkinson's disease and other α-synucleinopathies. We have developed α-synuclein oligomer/protofibril selective antibodies that reduce toxic α-synuclein in a human cell line and, upon intraperitoneal administration, in spinal cord of transgenic mice. Here, we investigated under which conditions and by which mechanisms such antibodies can be internalized by cells. For this purpose, human neuroglioma H4 cells were treated with either monoclonal oligomer/protofibril selective α-synuclein antibodies, linear epitope monoclonal α-synuclein antibodies, or with a control antibody. The oligomer/protofibril selective antibody mAb47 displayed the highest cellular uptake and was therefore chosen for additional analyses. Next, α-synuclein overexpressing cells were incubated with mAb47, which resulted in increased antibody internalization as compared to non-transfected cells. Similarly, regular cells exposed to mAb47 together with media containing α-synuclein displayed a higher uptake as compared to cells incubated with regular media. Finally, different Fcγ receptors were targeted and we then found that blockage of FcγRI and FcγRIIB/C resulted in reduced antibody internalization. Our data thus indicate that the robust uptake of the oligomer/protofibril selective antibody mAb47 by human CNS-derived cells is enhanced by extracellular α-synuclein and mediated via Fcγ receptors. Altogether, our finding lend further support to the belief that α-synuclein pathology can be modified by monoclonal antibodies and that these can target toxic α-synuclein species in the extracellular milieu. In the context of immunotherapy, antibody binding of α-synuclein would then not only block further aggregation but also mediate internalization and subsequent degradation of antigen-antibody complexes.


Assuntos
Anticorpos Monoclonais/metabolismo , Espaço Extracelular/metabolismo , Receptores de IgG/fisiologia , alfa-Sinucleína/metabolismo , Animais , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Humanos , Camundongos , Camundongos Transgênicos
6.
J Immunol ; 193(5): 2287-96, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25049358

RESUMO

Helicobacter pylori neutrophil-activating protein (HP-NAP) is a major virulence factor involved in H. pylori infection. Both HP-NAP protein and oncolytic viruses encoding HP-NAP have been suggested as immunotherapeutic anticancer agents and adjuvants for vaccination but with little known about its mode of action to activate adaptive immunity. Dendritic cells (DCs) are key players in bridging innate and adaptive immune responses, and in this study we aim to evaluate the effect of HP-NAP on DC maturation, migration, and induction of adaptive immune response. Maturation markers CD83, CD80, CD86, HLA-DR, CD40, and CCR7 were upregulated on human DCs after treatment with supernatants from HP-NAP adenovirus-infected cells. HP-NAP-activated DCs had a Th1 cytokine secretion profile, with high IL-12 and relatively low IL-10 secretion, and migrated toward CCL19. Ag-specific T cells were efficiently expanded by Ag-presenting HP-NAP-activated DCs, which is an important property of functionally mature DCs. Furthermore, intradermal injections of HP-NAP-encoding adenovirus in C57BL/6 mice enhanced resident DC migration to draining lymph nodes, which was verified by imaging lymph nodes by two-photon microscopy and by phenotyping migrating cells by flow cytometry. In conclusion, therapeutic effects of HP-NAP are mediated by maturation of DCs and subsequent activation of Ag-specific T cells in addition to provoking innate immunity.


Assuntos
Adenoviridae , Proteínas de Bactérias/imunologia , Movimento Celular/imunologia , Células Dendríticas/imunologia , Vetores Genéticos , Helicobacter pylori/imunologia , Células Th1/imunologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Células Dendríticas/citologia , Helicobacter pylori/genética , Humanos , Imunidade Inata/genética , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Camundongos , Células Th1/citologia
7.
Am J Hum Genet ; 90(2): 217-28, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22305530

RESUMO

Structural variations are among the most frequent interindividual genetic differences in the human genome. The frequency and distribution of de novo somatic structural variants in normal cells is, however, poorly explored. Using age-stratified cohorts of 318 monozygotic (MZ) twins and 296 single-born subjects, we describe age-related accumulation of copy-number variation in the nuclear genomes in vivo and frequency changes for both megabase- and kilobase-range variants. Megabase-range aberrations were found in 3.4% (9 of 264) of subjects ≥60 years old; these subjects included 78 MZ twin pairs and 108 single-born individuals. No such findings were observed in 81 MZ pairs or 180 single-born subjects who were ≤55 years old. Recurrent region- and gene-specific mutations, mostly deletions, were observed. Longitudinal analyses of 43 subjects whose data were collected 7-19 years apart suggest considerable variation in the rate of accumulation of clones carrying structural changes. Furthermore, the longitudinal analysis of individuals with structural aberrations suggests that there is a natural self-removal of aberrant cell clones from peripheral blood. In three healthy subjects, we detected somatic aberrations characteristic of patients with myelodysplastic syndrome. The recurrent rearrangements uncovered here are candidates for common age-related defects in human blood cells. We anticipate that extension of these results will allow determination of the genetic age of different somatic-cell lineages and estimation of possible individual differences between genetic and chronological age. Our work might also help to explain the cause of an age-related reduction in the number of cell clones in the blood; such a reduction is one of the hallmarks of immunosenescence.


Assuntos
Células Sanguíneas/fisiologia , Variações do Número de Cópias de DNA/genética , Genoma Humano , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Feminino , Humanos , Individualidade , Estudos Longitudinais , Pessoa de Meia-Idade , Mutação/genética , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
8.
Proc Natl Acad Sci U S A ; 109(39): 15877-81, 2012 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23019373

RESUMO

To produce genetically engineered T cells directed against prostate and breast cancer cells, we have cloned the T-cell receptor recognizing the HLA-A2-restricted T-cell receptor γ-chain alternate reading-frame protein (TARP)(4-13) epitope. TARP is a protein exclusively expressed in normal prostate epithelium and in adenocarcinomas of the prostate and breast. Peripheral blood T cells transduced with a lentiviral vector encoding the TARP-TCR proliferated well when exposed to peptide-specific stimuli. These cells exerted peptide-specific IFN-γ production and cytotoxic activity. Importantly, HLA-A2(+) prostate and breast cancer cells expressing TARP were also killed, demonstrating that the TARP(4-13) epitope is a physiologically relevant target for T-cell therapy of prostate and breast cancer. In conclusion, we present the cloning of a T cell receptor (TCR) directed against a physiologically relevant HLA-A2 epitope of TARP. To our knowledge this report on engineering of T cells with a TCR directed against an antigen specifically expressed by prostate cells is unique.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias da Mama/terapia , Engenharia Celular , Antígeno HLA-A2/imunologia , Imunidade Celular , Proteínas Nucleares/imunologia , Neoplasias da Próstata/terapia , Linfócitos T/imunologia , Transferência Adotiva , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/genética , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Feminino , Regulação da Expressão Gênica/imunologia , Antígeno HLA-A2/genética , Antígeno HLA-A2/metabolismo , Humanos , Masculino , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo
9.
Neurobiol Dis ; 69: 134-43, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24851801

RESUMO

Several lines of evidence suggest that accumulation of aggregated alpha-synuclein (α-synuclein) in the central nervous system (CNS) is an early pathogenic event in Parkinson's disease and other Lewy body disorders. In recent years, animal studies have indicated immunotherapy with antibodies directed against α-synuclein as a promising novel treatment strategy. Since large α-synuclein oligomers, or protofibrils, have been demonstrated to possess pronounced cytotoxic properties, such species should be particularly attractive as therapeutic targets. In support of this, (Thy-1)-h[A30P] α-synuclein transgenic mice with motor dysfunction symptoms were found to display increased levels of α-synuclein protofibrils in the CNS. An α-synuclein protofibril-selective monoclonal antibody (mAb47) was evaluated in this α-synuclein transgenic mouse model. As measured by ELISA, 14month old mice treated for 14weeks with weekly intraperitoneal injections of mAb47 displayed significantly lower levels of both soluble and membrane-associated protofibrils in the spinal cord. Besides the lower levels of pathogenic α-synuclein demonstrated, a reduction of motor dysfunction in transgenic mice upon peripheral administration of mAb47 was indicated. Thus, immunotherapy with antibodies targeting toxic α-synuclein species holds promise as a future disease-modifying treatment in Parkinson's disease and related disorders.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Imunização Passiva , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/terapia , alfa-Sinucleína/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Encéfalo/imunologia , Encéfalo/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Injeções Intraperitoneais , Masculino , Camundongos Transgênicos , Atividade Motora/fisiologia , Mutação , Transtornos Parkinsonianos/imunologia , Índice de Gravidade de Doença , Medula Espinal/imunologia , Medula Espinal/patologia , alfa-Sinucleína/genética
10.
Mol Ther ; 21(11): 2008-18, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23817216

RESUMO

Helicobacter pylori neutrophil-activating protein (HP-NAP) is a major virulence factor involved in H. pylori infection. HP-NAP can mediate antitumor effects by recruiting neutrophils and inducing Th1-type differentiation in the tumor microenvironment. It therefore holds strong potential as a therapeutic gene. Here, we armed a replication-selective, infection-enhanced adenovirus with secretory HP-NAP, Ad5PTDf35-[Δ24-sNAP], and evaluated its therapeutic efficacy against neuroendocrine tumors. We observed that it could specifically infect and eradicate a wide range of tumor cells lines from different origin in vitro. Insertion of secretory HP-NAP did not affect the stability or replicative capacity of the virus and infected tumor cells could efficiently secrete HP-NAP. Intratumoral administration of the virus in nude mice xenografted with neuroendocrine tumors improved median survival. Evidence of biological HP-NAP activity was observed 24 hours after treatment with neutrophil infiltration in tumors and an increase of proinflammatory cytokines such as tumor necrosis factor (TNF)-α and MIP2-α in the systemic circulation. Furthermore, evidence of Th1-type immune polarization was observed as a result of increase in IL-12/23 p40 cytokine concentrations 72 hours postvirus administration. Our observations suggest that HP-NAP can serve as a potent immunomodulator in promoting antitumor immune response in the tumor microenvironment and enhance the therapeutic effect of oncolytic adenovirus.


Assuntos
Adenoviridae/genética , Proteínas de Bactérias/uso terapêutico , Tumores Neuroendócrinos/terapia , Vírus Oncolíticos/genética , Adenoviridae/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citocinas/metabolismo , Feminino , Terapia Genética , Vetores Genéticos , Humanos , Camundongos , Camundongos Nus , Tumores Neuroendócrinos/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Terapia Viral Oncolítica , Vírus Oncolíticos/metabolismo , Recombinação Genética , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Fatores de Virulência/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
ACS Appl Mater Interfaces ; 16(17): 22665-22675, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647102

RESUMO

Multilayer neutron optics require precise control of interface morphology for optimal performance. In this work, we investigate the effects of different growth conditions on the interface morphology of Ni/Ti-based multilayers, with a focus on incorporating low-neutron-absorbing 11B4C and using different ion assistance schemes. Grazing-incidence small-angle X-ray scattering was used to probe the structural and morphological details of buried interfaces, revealing that the layers become more strongly correlated and the interfaces form mounds with increasing amounts of 11B4C. Applying high flux ion assistance during growth can reduce mound formation but lead to interface mixing, while a high flux modulated ion assistance scheme with an initial buffer layer grown at low ion energy and the top layer at higher ion energy prevents intermixing. The optimal condition was found to be adding 26.0 atom % 11B4C combined with high flux modulated ion assistance. A multilayer with a period of 48.2 Å and 100 periods was grown under these conditions, and coupled fitting to neutron and X-ray reflectivity data revealed an average interface width of only 2.7 Å, a significant improvement over the current state-of-the-art commercial Ni/Ti multilayers. Overall, our study demonstrates that the addition of 11B4C and the use of high flux modulated ion assistance during growth can significantly improve the interface morphology of Ni/Ti multilayers, leading to improved neutron optics performance.

12.
Sci Adv ; 10(7): eadl0402, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38354253

RESUMO

The utilization of polarized neutrons is of great importance in scientific disciplines spanning materials science, physics, biology, and chemistry. However, state-of-the-art multilayer polarizing neutron optics have limitations, particularly low specular reflectivity and polarization at higher scattering vectors/angles, and the requirement of high external magnetic fields to saturate the polarizer magnetization. Here, we show that, by incorporating 11B4C into Fe/Si multilayers, amorphization and smooth interfaces can be achieved, yielding higher neutron reflectivity, less diffuse scattering, and higher polarization. Magnetic coercivity is eliminated, and magnetic saturation can be reached at low external fields (>2 militesla). This approach offers prospects for substantial improvement in polarizing neutron optics with nonintrusive positioning of the polarizer, enhanced flux, increased data accuracy, and further polarizing/analyzing methods at neutron scattering facilities.

13.
Acta Oncol ; 52(5): 978-86, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23126547

RESUMO

BACKGROUND: Successful cell therapy relies on the identification and mass expansion of functional cells for infusion. Cryopreservation of cells is an inevitable step in most cell therapies which also entails consequences for the frozen cells. MATERIAL AND METHODS: This study assessed the impact of cryopreservation and the widely used protocol for rapid expansion of T lymphocytes. The effects on cell viability, immunocompetence and the impact on apoptotic and immunosuppressive marker expression were analyzed using validated assays. RESULTS AND CONCLUSION: Cryopreservation of lymphocytes during the rapid expansion protocol did not affect cell viability. Lymphocytes that underwent mass expansion or culture in high dose IL-2 were unable to respond to PHA stimulation by intracellular ATP production immediately after thawing (ATP = 16 ± 11 ng/ml). However, their reactivity to PHA was regained within 48 hours of recovery (ATP = 356 ± 61 ng/ml). Analysis of mRNA levels revealed downregulation of TGF-ß and IL-10 at all time points. Culture in high dose IL-2 led to upregulation of p73 and BCL-2 mRNA levels while FoxP3 expression was elevated after culture in IL-2 and artificial TCR stimuli. FoxP3 levels decreased after short-term recovery without IL-2 or stimulation. Antigen specificity, as determined by IFNγ secretion, was unaffected by cryopreservation but was completely lost after addition of high dose IL-2 and artificial TCR stimuli. In conclusion, allowing short-time recovery of mass expanded and cryopreserved cells before reinfusion could enhance the outcome of adoptive cell therapy as the cells regain immune competence and specificity.


Assuntos
Técnicas de Cultura de Células/métodos , Criopreservação/métodos , Imunoterapia Adotiva/métodos , Linfócitos T , Trifosfato de Adenosina/metabolismo , Apoptose/fisiologia , Sobrevivência Celular/fisiologia , Humanos , Tolerância Imunológica/fisiologia , Imunocompetência/fisiologia , Melanoma , Mitógenos/farmacologia , Fito-Hemaglutininas/farmacologia
14.
ACS Nano ; 17(24): 25565-25574, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38063207

RESUMO

It has recently been demonstrated that MoS2 with irregular interlayer rotations can achieve an extreme anisotropy in the lattice thermal conductivity (LTC), which is, for example, of interest for applications in waste heat management in integrated circuits. Here, we show by atomic-scale simulations based on machine-learned potentials that this principle extends to other two-dimensional materials, including C and BN. In all three materials, introducing rotational disorder drives the through-plane LTC to the glass limit, while the in-plane LTC remains almost unchanged compared to those of the ideal bulk materials. We demonstrate that the ultralow through-plane LTC is connected to the collapse of their transverse acoustic modes in the through-plane direction. Furthermore, we find that the twist angle in periodic moiré structures representing rotational order provides an efficient means for tuning the through-plane LTC that operates for all chemistries considered here. The minimal through-plane LTC is obtained for angles between 1 and 4° depending on the material, with the biggest effect in MoS2. The angular dependence is correlated with the degree of stacking disorder in the materials, which in turn is connected to the slip surface. This provides a simple descriptor for predicting the optimal conditions at which the LTC is expected to become minimal.

15.
Neurotherapeutics ; 20(1): 195-206, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36253511

RESUMO

Immunotherapy against amyloid-beta (Aß) is a promising option for the treatment of Alzheimer's disease (AD). Aß exists as various species, including monomers, oligomers, protofibrils, and insoluble fibrils in plaques. Oligomers and protofibrils have been shown to be toxic, and removal of these aggregates might represent an effective treatment for AD. We have characterized the binding properties of lecanemab, aducanumab, and gantenerumab to different Aß species with inhibition ELISA, immunodepletion, and surface plasmon resonance. All three antibodies bound monomers with low affinity. However, lecanemab and aducanumab had very weak binding to monomers, and gantenerumab somewhat stronger binding. Lecanemab was distinctive as it had tenfold stronger binding to protofibrils compared to fibrils. Aducanumab and gantenerumab preferred binding to fibrils over protofibrils. Our results show different binding profiles of lecanemab, aducanumab, and gantenerumab that may explain clinical results observed for these antibodies regarding both efficacy and side effects.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo
16.
J Virol ; 85(24): 13114-23, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21957304

RESUMO

Adenovirus serotype 5 (Ad5) is widely used as an oncolytic agent for cancer therapy. However, its infectivity is highly dependent on the expression level of coxsackievirus-adenovirus receptor (CAR) on the surfaces of tumor cells. Furthermore, infected cells overproduce adenovirus fiber proteins, which are released prior to cell lysis. The released fibers block CAR on noninfected neighboring cells, thereby preventing progeny virus entry. Our aim was to add a CAR-independent infection route to Ad5 to increase the infectivity of tumor cells with low CAR expression and prevent the fiber-masking problem. We constructed Ad5 viruses that encode the protein transduction domain (PTD) of the HIV-1 Tat protein (Tat-PTD) in hypervariable region 5 (HVR5) of the hexon protein. Tat-PTD functions as a cell-penetrating peptide, and Tat-PTD-modified Ad5 showed a dramatic increased transduction of CAR-negative cell lines compared to unmodified vector. Moreover, while tumor cell infectivity was severely reduced for Ad5 in the presence of fiber proteins, it was only marginally reduced for Tat-PTD-modified Ad5. Furthermore, because of the sequence alteration in the hexon HVR, coagulation factor X-mediated virus uptake was significantly reduced. Mice harboring human neuroblastoma and neuroendocrine tumors show suppressed tumor growths and prolonged survival when treated with Tat-PTD-modified oncolytic viruses. Our data suggest that modification of Ad5 with Tat-PTD in HVR5 expands its utility as an oncolytic agent.


Assuntos
Adenovírus Humanos/crescimento & desenvolvimento , Proteínas do Capsídeo/metabolismo , Neuroblastoma/terapia , Tumores Neuroendócrinos/terapia , Vírus Oncolíticos/crescimento & desenvolvimento , Internalização do Vírus , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Adenovírus Humanos/genética , Animais , Proteínas do Capsídeo/genética , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/patologia , Vírus Oncolíticos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sobrevida , Transdução Genética , Resultado do Tratamento , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
18.
J Immunol ; 182(5): 3105-11, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19234207

RESUMO

We recently reported that administration of tumor-specific bacteriophages initiates infiltration of neutrophilic granulocytes with subsequent regression of established B16 tumors. The aim of the current study was to investigate the mechanism of action of bacteriophage-induced tumor regression and to examine possible stimulatory effects of bacteriophages on macrophages. We observed that the mechanism of phage-induced tumor regression is TLR dependent as no signs of tumor destruction or neutrophil infiltration were observed in tumors in MyD88(-/-) mice in which TLR signaling is abolished. The microenvironment of bacteriophage-treated tumors was further analyzed by gene profiling through applying a low-density array preferentially designed to detect genes expressed by activated APCs, which demonstrated that the M2-polarized tumor microenvironment switched to a more M1-polarized milieu following phage treatment. Bacteriophage stimulation induced secretion of proinflammatory cytokines in both normal mouse macrophages and tumor-associated macrophages (TAMs) and increased expression of molecules involved in Ag presentation and costimulation. Furthermore, mouse neutrophils selectively migrated toward mediators secreted by bacteriophage-stimulated TAMs. Under these conditions, the neutrophils also exhibited increased cytotoxicity toward B16 mouse melanoma target cells. These results describe a close interplay of the innate immune system in which bacteriophages, located to the tumor microenvironment due to their specificity, stimulate TAMs to secrete factors that promote recruitment of neutrophils and potentiate neutrophil-mediated tumor destruction.


Assuntos
Bacteriófago M13/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/patologia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Animais , Apoptose/imunologia , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Cocultura , Feminino , Macrófagos/virologia , Melanoma Experimental/patologia , Melanoma Experimental/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Receptores Toll-Like/fisiologia
19.
Mol Ther ; 17(9): 1637-42, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19532140

RESUMO

Electroporation has, during the last years, proven to be a very successful delivery method for DNA vaccines and has now reached clinical evaluation. Although intramuscular electroporation is practical in animal models, intradermal electroporation might be more suitable for clinical administration. Skin is the most accessible organ of the body and has professional antigen-presenting cells in large amounts; thus, skin is an ideal target for DNA vaccine delivery. Moreover, intradermal electroporation has clear clinical benefits such as improved safety and tolerability. This article describes improvements for effective and tolerable DNA delivery to skin. The time of pulse delivery has been shortened by 90% and even pulse programs of 240-ms total duration generate robust immune responses. We show that a single vaccination using an optimized gene delivery generates (i) high and consistent protein expression in vivo, (ii) cytotoxic antigen-specific T cells expressing both IFNgamma and CD107a (lysosomal-associated membrane protein 1). Furthermore, application of a topical anesthetic cream prior to vaccination does not affect the number or function of the antigen-specific T cells induced. This suggests that local anesthesia can be used to further decrease the sensation of pulse delivery in patients.


Assuntos
Eletroporação/métodos , Pele/metabolismo , Vacinas de DNA/administração & dosagem , Animais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia , Linfócitos T/metabolismo , Vacinas de DNA/imunologia
20.
Evol Appl ; 12(7): 1360-1370, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31417620

RESUMO

Human-modified habitats rarely yield outcomes that are aligned with conservation ideals. Landscapes that are subdivided by roads are no exception, precipitating negative impacts on populations due to fragmentation, pollution, and road kill. Although many populations in human-modified habitats show evidence for local adaptation, rarely does environmental change yield outright benefits for populations of conservation interest. Contrary to expectations, we report surprising benefits experienced by amphibian populations breeding and dwelling in proximity to roads. We show that roadside populations of the wood frog, Rana sylvatica, exhibit better locomotor performance and higher measures of traits related to fitness compared with frogs from less disturbed environments located further away from roads. These results contrast previous evidence for maladaptation in roadside populations of wood frogs studied elsewhere. Our results indicate that altered habitats might not be unequivocally detrimental and at times might contribute to metapopulation success. While the frequency of such beneficial outcomes remains unknown, their occurrence underscores the complexity of inferring consequences of environmental change.

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