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1.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38984882

RESUMO

Due to the limited maximum output power of the pulsers based on avalanche transistors, high-power ultrawideband (UWB) radiation systems usually synthesize plenty of modules simultaneously to achieve a high peak effective potential (rEp). However, this would lead to an increased aperture size as well as a narrower beam, which would limit their applications in intentional electromagnetic interference fields. In this paper, a high-power UWB radiation system with beam broadening capacity is developed. To achieve beam broadening in the time domain, a power-law time delay distribution method is proposed and studied by simulation, and then the relative excitation time delays of the modules are optimized to achieve higher rEp and avoid beam splitting in the beam broadening mode. In order to avoid false triggering of the pulser elements when implementing the beam broadening, the mutual coupling effect in the system is analyzed and suppressed by employing onboard high-pass filters, since the mutual coupling effect is much more severe in the low-frequency range. Finally, a radiation system with 36 modules is developed. Measuring results indicate that in the high-rEp mode, the developed system could achieve a maximum effective potential rEp of 313.6 kV and a maximum pulse-repetition-rate of 20 kHz. In the beam broadening mode, its half-peak-power beam width in the H-plane is broadened from the original value of 3.9° to 7.9°, with a maximum rEp of 272.9 kV. The polarization direction of the system could be flexibly adjusted by a built-in motor.

2.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117201

RESUMO

In this paper, a kind of tightly coupled array (TCA) with time-domain beam scan is developed for the radiation of high-power ultrawideband (UWB) electromagnetic pulses, and the peak-power pattern is proposed to characterize the directivity. First, the active voltage standing wave ratio (AVSWR) bandwidth of the TCA is optimized, which is the precondition for the beam scan. It indicates that the lower-cutoff frequency (LCF) is inversely proportional to the total length of the whole array; an increase in the distance between the array and the ground plane could remarkably reduce the LCF; and an increase in the element number can also decrease the LCF because of the increase in length, but more elements would make the center elements difficult to match in the low-frequency range, so there is a limitation on the number of elements for a certain LCF. Based on these results, a six-element linear array is designed. Then, the definition of the peak-power pattern is proposed to characterize the directivity of the UWB pulsed antenna. Finally, the optimized six-element array is developed, and the measured working band is 276 MHz-6.4 GHz (AVSWR < 3). The effective potential gain is 1.76, and it improves by 51.7% with a reduction in the aperture area by 68.4% compared with the previous TCA, which means that the aperture efficiency is remarkably improved. The half-power beam width of the developed TCA with the scan angle of 0° is 45°. The time-domain beam scan could be performed with time-delay feeding lines, and the maximum scan angle is over ±30° in the E-plane. The developed TCA can be applied for the generation of high-power electromagnetic environments for the study of intentional electromagnetic interference.

3.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37510993

RESUMO

Immunotherapies including adaptive immune checkpoint inhibitors (ICIs) and chimeric antigen receptor (CAR) T cells, have developed the treatment of cancer in clinic, and most of them focus on activating T cell immunity. Although these strategies have obtained unprecedented clinical responses, only limited subsets of cancer patients could receive long-term benefits, highlighting the demand for identifying novel targets for the new era of tumor immunotherapy. Innate immunity has been demonstrated to play a determinative role in the tumor microenvironment (TME) and influence the clinical outcomes of tumor patients. A thorough comprehension of the innate immune cells that infiltrate tumors would allow for the development of new therapeutics. In this review, we outline the role and mechanism of innate immunity in TME. Moreover, we discuss innate immunity-based cancer immunotherapy in basic and clinical studies. Finally, we summarize the challenges in sufficiently motivating innate immune responses and the corresponding strategies and measures to improve anti-tumor efficacy. This review could aid the comprehension of innate immunity and inspire the creation of brand-new immunotherapies for the treatment of cancer.


Assuntos
Neoplasias , Humanos , Neoplasias/patologia , Imunidade Inata , Imunoterapia , Linfócitos T , Biologia , Microambiente Tumoral
4.
Immunotherapy ; 15(3): 175-187, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36727256

RESUMO

Background: Only a subset of B-cell lymphoma (BCL) patients can benefit from immune checkpoint inhibitors targeting PD-1/PD-L1. Materials & methods: In the A20 model, SIRPα-Fc and anti-PD-L1 were employed to target CD47 and PD-L1 simultaneously. Flow cytometry, immunofluorescence and quantitative polymerase chain reaction were used to unravel the potential mechanisms. Results: Simultaneously targeting CD47 and PD-L1 activated CD8+ T cells with an increased release of effector molecules. Furthermore, infiltration of F4/80+iNOS+ M1 macrophages was enhanced by the dual therapy. Conclusion: Anti-CD47 therapy could sensitize BCL tumors to anti-PD-L1 therapy in a CD8+ T-cell- and M1-macrophage-dependent manner by promoting cytotoxic lymphocyte infiltration, which may provide a potential strategy for BCL treatment by simultaneously targeting CD47 and PD-L1.


Immune checkpoint inhibitors targeting PD-1/PD-L1 have become effective agents for cancer treatment. However, only a minority of patients benefit from this treatment in the clinic because of the limited response rate. Targeting CD47/SIRPα restores macrophage function and improves the response of antitumor immunity. Here, combination immunotherapy targeting CD47/SIRPα and PD-1/PD-L1 was investigated to increase the response rate and antitumor effect of PD-L1 monotherapy in B-cell lymphoma (BCL). This study broadens the application of the combination therapy and provided a promising strategy for B-cell lymphoma treatment by simultaneous targeting of PD-1/PD-L1 and CD47/SIRPα axis.


Assuntos
Linfoma de Células B , Neoplasias , Humanos , Antígeno CD47 , Linfócitos T CD8-Positivos , Imunoterapia , Linfoma de Células B/tratamento farmacológico , Macrófagos , Antígeno B7-H1/metabolismo
5.
Rev Sci Instrum ; 93(4): 044705, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35489880

RESUMO

In this paper, a high-power ultra-wideband radiation system, composed of multiply radiation modules, is developed based on the space-synthesis method. The radiation module mainly consists of a transistorized pulser, a 2 × 2 combined antenna array, and a power divider. To improve the out parameters [the amplitude, the pulse repetition frequency (PRF), and the rise time] of the transistorized pulser based on the Marx circuit, the influence of the traveling wave process on the output pulse must be concerned. Based on the theoretical analysis, the printed circuit board circuit parameters and the circuit structure of the pulser are optimized. To improve the power synthesis efficiency, the pulse jitter characteristic of the pulser is improved by replacing the conventional base triggering mode with the collector voltage ramp triggering mode for the first-stage avalanche transistor in the pulser. The previous optimized antenna array is utilized in this radiation system, which has a better radiation performance in the prescribed aperture area. In addition, based on the gradient microstrip structure, the power divider integrated with the pulser is designed, which has the advantages of wide bandwidth, low loss, and light weight. Experimental results show that the peak effective potential rEp of the radiation system of 20 radiation modules is 221.8 kV, the maximum PRF could reach 10 kHz, and the half-power radiation angles of its radiation field are about 5° in both the E plane and the H plane. More radiation modules could be integrated into the system to achieve a higher electric field in the future.

6.
Rev Sci Instrum ; 92(7): 074701, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340433

RESUMO

In this article, a Narrow-Width Combined Antenna (NWCA) is proposed for the compact design of high-power ultra-wideband (UWB) systems. The dependence of performances on three dimensions of the combined antenna is investigated so as to minimize its size with a given excitation. It indicates that the working process of the combined antenna can be divided into two stages: (1) energy transmitted from the feeding point to the aperture by the TEM horn structure, and during this stage, the passband is determined by the effect of the impedance taper, which is related to the length and aperture impedance of the antenna, and (2) energy radiated to the free space from the aperture, during which the height of the aperture is the dominant factor. Therefore, the three dimensions of the combined antenna can be appropriately adjusted to make the antenna more compact. Thus, the NWCA is designed by reducing the width and making a slight compensation in height and/or length. Compared with the conventional cubic antenna, the aperture area of the developed NWCA is reduced by 47%, whereas the amplitude of the radiating field only reduces by 2.5% with the given pulsed excitation at the cost of a slight decrease in the pulse duration. It demonstrates that the NWCA is an effectively compact design for the combined antenna in the application of the radiation of the high-power UWB pulse.

7.
Rev Sci Instrum ; 92(1): 014709, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514195

RESUMO

In this Note, a type of Differential Switched Oscillator (DSWO) system is developed and compared with the conventional single-ended switched oscillator; the power capacity of the DSWO is twice with the same insulation level and twice total length. The DSWO system consists of a differential high-voltage pulsed source, a DSWO, and a pair of differential helical antennas. The differential pulsed source is based on the hydrogen thyratron and pulsed transformer whose peak voltage can theoretically reach ±100 kV to break down the high-pressure switch, whose limiting gas pressure is 25 atm; the DSWO is designed to generate a damped oscillation pulse with a central frequency of 300 MHz, which is also the central frequency of the differential helical antennas. Thus, a damped oscillation pulse can be produced and radiated to generate high-power mesoband circularly polarized electromagnetic fields, and the axial ratio is 1.98. According to the measured results, the central frequency of the developed DSWO is 284 MHz, the percent bandwidth of the radiating field is 11%, and the amplitude of the far-field effective potential is 105 kV.

8.
RSC Adv ; 12(1): 517-527, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-35424524

RESUMO

Exploring a new type of smart membrane with tunable separation performance is a promising area of research. In this study, new light-responsive metal-organic framework [Co(azpy)] sheets were prepared by a facile microwave method for the first time, and were then incorporated into a polymer matrix to fabricate smart mixed matrix membranes (MMMs) applied for flue gas desulfurization and decarburization. The smart MMMs exhibited significantly elevated SO2(CO2)/N2 selectivity by 184(166)% in comparison with an unfilled polymer membrane. The light-responsive characteristic of the smart MMMs was investigated, and the permeability and selectivity of the Co(azpy) sheets-loaded smart MMMs were able to respond to external light stimuli. In particular, the selectivity of the smart MMM at the Co(azpy) content of 20% for the SO2/N2 system could be switched between 341 and 211 in situ irradiated with Vis and UV light, while the SO2 permeability switched between 58 Barrer and 36 Barrer, respectively. This switching influence was mainly ascribed to the increased SO2 adsorption capacity in the visible light condition, as verified by adsorption test. The CO2 permeability and CO2/N2 selectivity of MMMs in the humidified state could achieve 248 Barrer and 103.2, surpassing the Robeson's upper bound reported in 2019.

9.
Inorg Chem ; 59(7): 4435-4442, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32167757

RESUMO

Two novel thorium-based metal-organic frameworks (MOFs), namely Th-SINAP-7 and Th-SINAP-8, have been synthesized via the solvothermal reactions of thorium nitrate and 1,4- or 2,6-naphthalenedicarboxylic acid in the presence of acid modulators. Bearing the rigid aromatic architectures, Th-SINAP-7 and Th-SINAP-8 exhibit exceptional chemical (from pH 1 to 12) and thermal stabilities (up to 520 °C), as well as ionizing radioresistance (2 × 105 Gy ß and γ irradiations). The highly porous nature and conjugated π-electrons of naphthalene on the organic linkers endow high affinity of both MOFs toward I2 molecules owning to the charge transfer between π-electrons of the host networks and the guest iodine molecules, as evidenced by combined techniques including of FTIR, PXRD, SEM-EDS, UV-vis spectroscopy, XPS, and Raman spectroscopy. Particularly, Th-SINAP-8 can efficiently remove >99% I2 from cyclohexane solution and exhibit guest uptake of iodine vapor with an adsorption capacity of 473 mg/g.

10.
Front Chem ; 8: 58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117883

RESUMO

Dual-filler MMMs have attracted special interests in recent years because of the possibility of producing synergetic effect. This study is aimed at exploring the underlying synergy between two-dimensional (2D) nanosheets and a non-2D filler in mixed matrix membranes for gas separation. MXene or graphene oxide (GO) as typical nanosheet filler is selected to be in pair with a non-2D filler, SiO2 or halloysite nanotubes (HNTs), with Pebax as the polymer matrix. In this way, four pairs of binary fillers are designed and the corresponding four groups of MMMs are fabricated. By tuning the mass ratio of binary fillers, synergetic effect is found for each group of MMMs. However, the two 2D fillers found different preferential non-2D partners. GO works better with HNTs than SiO2, while MXene prefers SiO2 to HNTs. To be noted, GO/HNTs renders the membranes the maximum enhancement of CO2 permeability (153%) and CO2/N2 selectivity (72%) compared to Pebax control membrane, while each of them as single filler only brought about very limited enhancement of CO2 separation performance. The possible mechanisms are thoroughly discussed in terms of filler dispersion, nanosheet flexibility, and the tortuosity and connectivity of the surface diffusion pathways along nanosheets.

11.
J Immunother Cancer ; 7(1): 346, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31829270

RESUMO

BACKGROUND: Inhibitors targeting VEGF and VEGFR are commonly used in the clinic, but only a subset of patients could benefit from these inhibitors and the efficacy was limited by multiple relapse mechanisms. In this work, we aimed to investigate the role of innate immune response in anti-angiogenic therapy and explore efficient therapeutic strategies to enhance efficacy of anti-angiogenic therapy against non-small cell lung cancer (NSCLC). METHODS: Three NSCLC tumor models with responses to VEGF inhibitors were designed to determine innate immune-related underpinnings of resistance to anti-angiogenic therapy. Immunofluorescence staining, fluorescence-activated cell sorting and immunoblot analysis were employed to reveal the expression of immune checkpoint regulator CD47 in refractory NSCLC. Metastatic xenograft models and VEGFR1-SIRPα fusion protein were applied to evaluate the therapeutic effect of simultaneous disruption of angiogenetic axis and CD47-SIRPα axis. RESULTS: Up-regulation of an innate immunosuppressive pathway, CD47, the ligand of the negative immune checkpoint regulator SIRPα (signal regulatory protein alpha), was observed in NSCLC tumors during anti-angiogenic therapy. Further studies revealed that CD47 upregulation in refractory lung tumor models was mediated by TNF-α/NF-κB1 signal pathway. Targeting CD47 could trigger macrophage-mediated elimination of the relapsed NSCLC cells, eliciting synergistic anti-tumor effect. Moreover, simultaneously targeting VEGF and CD47 by VEGFR1-SIRPα fusion protein induced macrophages infiltration and sensitized NSCLC to angiogenesis inhibitors and CD47 blockade. CONCLUSIONS: Our research provided evidence that CD47 blockade could sensitize NSCLC to anti-angiogenic therapy and potentiate its anti-tumor effects by enhancing macrophage infiltration and tumor cell destruction, providing novel therapeutics for NSCLC by disrupting CD47/SIRPα interaction and angiogenetic axis.


Assuntos
Inibidores da Angiogênese/farmacologia , Antígeno CD47/antagonistas & inibidores , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neovascularização Patológica/metabolismo , Animais , Antígenos de Diferenciação , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Modelos Moleculares , Neovascularização Patológica/tratamento farmacológico , Receptores Imunológicos/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Mikrochim Acta ; 186(9): 603, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385118

RESUMO

A flexible adhesive tape decorated with SERS-active silver nanorods (AgNRs) in the form of an array nanostructure is described. The tape was constructed by transferring the AgNRs nanostructures from silicon to the transparent tape by a "paste & peel off" procedure. The transparent, sticky, and flexible properties of commercial tapes allow almost any SERS-inactive irregular surface to be detected in-situ by pasting the SERS tape onto the position to be analyzed. Three examples for an analytical application are presented, viz. determination of (a) tetramethylthiuram disulfide and thiabendazole (two pesticides), (b) colorants in the gel of a writing pen, and (c) the fluorophore Rhodamine B. The tetramethylthiuram disulfide on apple surface was rapidly detected with a LOD of 28.8 ng·cm-2. The AgNRs effectively quenched the fluorescence of the matrix and fluorophores, this enabling the colorants and Rhodamine B to be identified. The results demonstrated that the SERS tape can be used for versatile in-situ detection. Conceivably, it may find applications in food analysis, non-invasive identification, environmental monitoring, and in other areas of daily life. Graphic abstract A flexible and adhesive SERS active tape decorated with silver nanorods (AgNRs) arrays was constructed through a "paste & peel off" method. It can be used as a versatile in situ analysis platform for various applications.

13.
Cell Death Dis ; 10(9): 626, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427566

RESUMO

Lung adenocarcinoma (LUAD), which comprises over 50% of all cases of non-small-cell lung cancer, has a poor prognosis and requires novel therapeutic approaches. The sonic Hedgehog (Shh) pathway, which plays a crucial role in differentiation, proliferation, and survival of cancer cells, is likely to be activated in LUADs, suggesting the Shh pathway as a potential therapeutic target for LUAD treatment. In this study, we reported that vismodegib, an inhibitor of the Shh pathway, only elicited minor antitumor efficacy in A549 and NCI-H1975 LUAD cells as well as in the xenograft tumors, with overexpressed GLI2 and increased autophagic activity. The aberrant autophagy in LUAD cells was further confirmed by the three main stages of autophagic flux, including the formation of autophagosomes, the fusion of autophagosomes with lysosomes, and degradation of autophagosomes in lysosomes. Furthermore, inhibition of autophagy by siRNA against ATG5 or ATG7 rescued the sensitivity of A549 and NCI-H1975 LUAD cells to vismodegib in vitro. Meanwhile, administration of the pharmaceutical inhibitor of autophagy, chloroquine, contributed to the enhanced anti-LUAD efficacy of vismodegib in vivo, probably through overproduction of ROS, acceleration of apoptosis, and suppression of GLI2 in LUAD tissues. In summary, our research revealed that downregulating autophagy facilitated the anti-LUAD efficacy of the Shh pathway suppression, thus highlighting a potential approach for LUAD therapy via simultaneously targeting the Shh signaling and autophagy pathway.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/metabolismo , Proteínas Hedgehog/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Gli2 com Dedos de Zinco/metabolismo , Células A549 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Anilidas/farmacologia , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Proteínas Hedgehog/metabolismo , Xenoenxertos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Piridinas/farmacologia , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Appl Microbiol Biotechnol ; 103(12): 4825-4838, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053913

RESUMO

Arginase I has been documented to impair T cell function and attenuate cellular immunity, however, there is little evidence to reveal the effect of arginase I on macrophage function. Recently, recombinant human arginase I (rhArg) has been developed for cancer therapy and is in clinical trial for hepatocellular carcinoma, whereas the potential immunosuppression induced by rhArg limited its therapeutic efficacy. To improve the clinical outcome of rhArg, addressing the immune suppression appears to be particularly important. In this study, we found that rhArg attenuated macrophage functions, including inhibiting macrophage cell proliferation, nitric oxide (NO) and reactive oxygen species (ROS) production, cytokine secretion, MHC-II surface expression, and phagocytosis, thereby inducing immunosuppression in lipopolysaccharides (LPS)/interferon-γ (IFN-γ)-activated macrophages. Notably, we observed that rhArg downregulated autophagy in activated macrophages. Moreover, application of trehalose (an autophagy inducer) significantly restored the impaired immune function in activated macrophages, suggesting the essential role of autophagy in rhArg-induced immunosuppression. To further illustrate the effect of autophagy in immunosuppression, we then observed the effect of 3-MA (an autophagy inhibitor) on the immune function of macrophages. As expected, inhibiting autophagy by 3-MA attenuated immune functions in activated macrophages. Collectively, this study elucidated that rhArg induced immunosuppression in activated macrophages via inhibiting autophagy, providing potential strategy to ameliorate the immune suppression which is of great significance to cancer therapy and facilitating the development of rhArg as a potential therapy for malignant carcinomas.


Assuntos
Arginase/imunologia , Autofagia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunossupressores/farmacologia , Macrófagos/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Arginase/genética , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Citocinas/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Neoplasias Hepáticas/terapia , Macrófagos/patologia , Camundongos , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/imunologia , Trealose/farmacologia
15.
Biomaterials ; 187: 66-80, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30296739

RESUMO

Hepatocellular injury is the pathological hallmark of hepatitis and a crucial driver for the progression of liver diseases, while the treatment options are commonly restricted. Interleukin-22 (IL-22) has attracted special attention as a potent survival factor for hepatocytes that both prevents and repairs the injury of hepatocytes through activation of STAT3 signaling pathway. We hypothesized that the ability to generate potent expression of IL-22 locally for the treatment of severe hepatocellular injury in hepatitis was a promising strategy to enhance efficacy and overcome off-target effects. Accordingly, we developed a polypeptide penetratin-based hybrid nanoparticle system (PDPIA) carrying IL-22 gene by a self-assembly process. This nanocomplex modified with penetratin featured direct translocation across the cellular or endosomal membrane but mild zeta-potential to facilitate the high cellular internalization and endosomal escape of the gene cargos as well as scarcely Kupffer cells uptake. More importantly, PDPIA afforded preferential liver accumulation and predominant hepatocytes internalization following systemic administration, which showed pharmacologically suitable organ and sub-organ-selective properties. Subsequent studies confirmed a considerable protective role of PDPIA in a model of severe hepatitis induced by concanavalin A, evidenced by reduced hepatocellular injury and evaded immune response. The locally expressed IL-22 by PDPIA activated STAT3/Erk signal transduction, and thus promoted hepatocyte regeneration, inhibited reactive oxygen species (ROS) accumulation as well as prevented the dysfunction of mitochondrial. In addition, this system did not manifest side effects or systemic toxicity in mice. Collectively, the high versatility of PDPIA rendered its promising applications might be an effective agent to treat various hepatic disorders.


Assuntos
Peptídeos Penetradores de Células/química , Portadores de Fármacos/química , Hepatite/terapia , Interleucinas/metabolismo , Nanopartículas/química , Animais , Linhagem Celular , Sobrevivência Celular , Concanavalina A , Dendrímeros/química , Terapia Genética , Hepatite/etiologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Interleucinas/genética , Células de Kupffer/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Potencial da Membrana Mitocondrial , Camundongos Endogâmicos BALB C , Polietilenoglicóis/química , Espécies Reativas de Oxigênio/metabolismo , Interleucina 22
16.
Front Immunol ; 9: 1799, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123222

RESUMO

Background: Antibody drug conjugate (ADC) showed potent therapeutic efficacy in several types of cancers. The role of autophagy in antitumor effects of ADC remains unclear. Methods: In this study, the ADC, Rituximab-monomethyl auristatin E (MMAE) with a Valine-Citrulline cleavable linker, was designed to investigate its therapeutic efficacy against non-Hodgkin lymphoma (NHL) as well as the underlying mechanisms. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) was used to detect growth inhibition in B-cell lymphoma cell lines, Ramos and Daudi cells, which were treated by Rituximab-MMAE alone or combined with autophagy conditioner. Apoptosis was detected by flow cytometry and immunohistochemistry, and apoptosis inhibitor was employed to discover the relationship between autophagy and apoptosis during the Rituximab-MMAE treatment. Autophagy was determined by three standard techniques which included confocal microscope, transmission electron microscope, and western blots. Ramos xenograft tumors in BALB/c nude mice were established to investigate the antitumor effect of combination use of Rituximab-MMAE and autophagy conditioner in B-NHL therapy. Results: Our results showed that Rituximab-MMAE elicited caspase-3-dependent apoptosis in NHL cells and exhibited potent therapeutic efficacy in vivo. Autophagy, which was characterized by upregulated light chain 3-II expression, and accumulation of autophagosomes, was triggered during the Rituximab-MMAE treatment. Meanwhile, inactivation of Akt/mTOR pathway was shown to be involved in the autophagy triggered by Rituximab-MMAE, indicating a probable mechanism of the ADC-initiated autophagy. Importantly, inhibition of autophagy by chloroquine suppressed the Rituximab-MMAE-induced apoptosis, while activating autophagy by rapamycin significantly enhanced the therapeutic effect of Rituximab-MMAE both in vitro and in vivo. Conclusion: Our data elucidated the critical relationship between autophagy and apoptosis in Rituximab-MMAE-based therapy and highlighted the potential approach for NHL therapy by combined administration of the ADC and autophagy activator.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Autofagia/efeitos dos fármacos , Imunoconjugados/farmacologia , Oligopeptídeos , Rituximab/farmacologia , Animais , Antineoplásicos Imunológicos/química , Apoptose/efeitos dos fármacos , Autofagossomos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Imunoconjugados/química , Camundongos , Terapia de Alvo Molecular , Oligopeptídeos/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rituximab/química , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Biochem Soc Trans ; 46(4): 1003-1012, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30065108

RESUMO

The family of Rho GTPases are involved in the dynamic control of cytoskeleton reorganization and other fundamental cellular functions, including growth, motility, and survival. Rac1, one of the best characterized Rho GTPases, is an established effector of receptors and an important node in signaling networks crucial for tumorigenesis and metastasis. Rac1 hyperactivation is common in human cancer and could be the consequence of overexpression, abnormal upstream inputs, deregulated degradation, and/or anomalous intracellular localization. More recently, cancer-associated gain-of-function mutations in Rac1 have been identified which contribute to tumor phenotypes and confer resistance to targeted therapies. Deregulated expression/activity of Rac guanine nucleotide exchange factors responsible for Rac activation has been largely associated with a metastatic phenotype and drug resistance. Translating our extensive knowledge in Rac pathway biochemistry into a clinical setting still remains a major challenge; nonetheless, remarkable opportunities for cancer therapeutics arise from promising lead compounds targeting Rac and its effectors.


Assuntos
Neoplasias/patologia , Proteínas rac de Ligação ao GTP/metabolismo , Progressão da Doença , Suscetibilidade a Doenças , Humanos , Neoplasias/metabolismo , Transdução de Sinais
18.
Appl Microbiol Biotechnol ; 102(15): 6503-6513, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29754163

RESUMO

Glioblastoma, characterized by extensive microvascular proliferation and invasive tumor growth, is one of the most common and lethal malignancies in adults. Benefits of the conventional anti-angiogenic therapy were only observed in a subset of patients and limited by diverse relapse mechanism. Fortunately, recent advances in cancer immunotherapy have offered new hope for patients with glioblastoma. Herein, we reported a novel dual-targeting therapy for glioblastoma through simultaneous blockade of VEGF and CD47 signaling. Our results showed that VEGFR1D2-SIRPαD1, a VEGF and CD47 bispecific fusion protein, exerted potent anti-tumor effects via suppressing VEGF-induced angiogenesis and activating macrophage-mediated phagocytosis. Meanwhile, autophagy was activated by VEGFR1D2-SIRPαD1 through inactivating Akt/mTOR and Erk pathways in glioblastoma cells. Importantly, autophagy inhibitor or knockdown of autophagy-related protein 5 potentiated VEGFR1D2-SIRPαD1-induced macrophage phagocytosis and cytotoxicity against glioblastoma cells. Moreover, suppression of autophagy led to increased macrophage infiltration, angiogenesis inhibition, and tumor cell apoptosis triggered by VEGF and CD47 dual-targeting therapy, thus eliciting enhanced anti-tumor effects in glioblastoma. Our data revealed that VEGFR1D2-SIRPαD1 alone or in combination with autophagy inhibitor could effectively elicit potent anti-tumor effects, highlighting potential therapeutic strategies for glioblastoma through disrupting angiogenetic axis and CD47-SIRPα anti-phagocytic axis alone or in combination with autophagy inhibition.


Assuntos
Autofagia/efeitos dos fármacos , Antígeno CD47/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Xenoenxertos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fagocitose/efeitos dos fármacos
19.
Front Immunol ; 9: 758, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29692782

RESUMO

Autoimmune hepatitis (AIH) is a progressive inflammatory disorders of unknown etiology, characterized by immune-mediated destruction of hepatocytes and massive production of cytokines. Interleukin-1ß is a pleiotropic proinflammatory cytokine and well known to be critical in a variety of autoimmune diseases. However, the role of interleukin-1ß (IL-1ß) in AIH is still indistinct. Here, we first investigated the significance of NOD-like receptor protein 3 (NLRP3) inflammasome-dependent IL-1ß in the pathogenesis of AIH with a murine model of immune-mediated hepatitis induced by Concanavalin A (ConA). In ConA-treated mice, pathogenic elevated NLRP3, Cleaved caspase-1 and IL-1ß levels, as well as an inflammatory cell death known as pyroptosis predominantly occurred in the livers. Strikingly, NLRP3-/- and caspase-1-/- mice were broadly protected from hepatitis as determined by decreased histological liver injury, serum aminotransferase (ALT)/aspartate transaminase levels, and pyroptosis. In vivo intervention with recombinant human interleukin-1 receptor antagonist (rhIL-1Ra) strongly suppressed ConA-induced hepatitis by decreasing tumor necrosis factor-alpha (TNF-α) and interleukin-17 (IL-17) secretion, and inflammatory cell infiltration into livers. Additionally, rhIL-1Ra-pretreated mice developed significantly reduced NLRP3 inflammasome activation and reactive oxygen species (ROS) generation. Scavenging of ROS by N-acetyl-cysteine also attenuated NLRP3 inflammasome activation and liver inflammation, indicating that the essential role of ROS in mediating NLRP3 inflammasome activation in ConA-induced hepatitis. In conclusion, our results demonstrated that NLRP3 inflammasome-dependent IL-1ß production was crucial in the pathogenesis of ConA-induced hepatitis, which shed light on the development of promising therapeutic strategies for AIH by blocking NLRP3 inflammasome and IL-1ß.


Assuntos
Hepatite Autoimune/imunologia , Inflamassomos/imunologia , Interleucina-1beta/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Animais , Concanavalina A/toxicidade , Hepatite Autoimune/metabolismo , Hepatite Autoimune/patologia , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
20.
Carcinogenesis ; 39(5): 689-699, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29538621

RESUMO

CD47-targeting immune checkpoint inhibitors have been investigated for immunotherapy of several cancers, glioblastoma, one of the most common tumors in brain, was still a challenge for CD47-targeting therapy. Herein, we reported novel strategies for glioblastoma therapy via blocking CD47-signal regulatory protein-α (SIRPα) by SIRPα-Fc alone or in combination with autophagy inhibition. Our results showed that SIRPα-Fc increased macrophages-triggered cytotoxicity and phagocytosis of glioblastoma cells then elicited potent anti-tumor efficacy. During the treatment, SIRPα-Fc induced autophagy and autophagic flux in glioblastoma cells and Akt/mammalian target of rapamycin (mTOR) inactivation was participated in the autophagy activation. Inhibition of autophagy by pharmacological agents or small-interfering RNA increased SIRPα-Fc-triggered macrophage phagocytosis and cytotoxicity. Importantly, when compared with SIRPα-Fc treatment, blocking both CD47/SIRPα and autophagy significantly increased infiltration of macrophages and apoptosis of tumor cells, triggering potentiated anti-glioblastoma effect and extended median survival. Further experiments showed that adaptive immune response, including CD8+ T-cell subsets, was also played a crucial role in SIRPα-Fc-induced glioblastoma rejection. Our results indicated that SIRPα-Fc alone or combined with autophagy inhibitors elicited potent anti-glioblastoma effect, highlighting potential therapeutic strategies of glioblastoma via blocking CD47/SIRPα alone or in combination with autophagy inhibitor.


Assuntos
Autofagia/imunologia , Antígeno CD47/metabolismo , Glioblastoma/metabolismo , Glioblastoma/terapia , Receptores Imunológicos/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Glioblastoma/imunologia , Humanos , Imunoterapia/métodos , Macrófagos/imunologia , Camundongos , Fagocitose/imunologia , Serina-Treonina Quinases TOR/metabolismo
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