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1.
Nano Lett ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885458

RESUMO

The metal-semiconductor interface fabricated by conventional methods often suffers from contamination, degrading transport performance. Herein, we propose a one-pot chemical vapor deposition (CVD) process to create a two-dimensional (2D) MoO2-MoSe2 heterostructure by growing MoO2 seeds under a hydrogen environment, followed by depositing MoSe2 on the surface and periphery. The ultraclean interface is verified by cross-sectional scanning transmission electron microscopy and photoluminescence. Along with the high work function of semimetallic MoO2 (Ef = -5.6 eV), a high-rectification Schottky diode is fabricated based on this heterostructure. Furthermore, the Schottky diode exhibits an excellent photovoltaic effect with a high open-circuit voltage of 0.26 eV and ultrafast photoresponse, owing to the naturally formed metal-semiconductor contact with suppressed pinning effect. Our method paves the way for the fabrication of an ultraclean 2D metal-semiconductor interface, without defects or contamination, offering promising prospects for future nanoelectronics.

2.
ACS Appl Mater Interfaces ; 16(25): 31875-31876, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920006
4.
Nanomaterials (Basel) ; 13(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37570546

RESUMO

Low-threshold lasing under pulsed optical pumping is demonstrated in GaN-based microrod cavities at room temperature, which are fabricated on the patterned sapphire substrates (PSS). Because the distribution of threading dislocations (TDs) is different at different locations, a confocal micro-photoluminescence spectroscopy (µ-PL) was performed to analyze the lasing properties of the different diameter microrods at the top of the triangle islands and between the triangle islands of the PSS substrates, respectively. The µ-PL results show that the 2 µm-diameter microrod cavity has a minimum threshold of about 0.3 kW/cm2. Whispering gallery modes (WGMs) in the microrod cavities are investigated by finite-difference time-domain simulation. Combined with the dislocation distribution in the GaN on the PSS substrates, it is found that the distribution of the strongest lasing WGMs always moves to the region with fewer TDs. This work reveals the connection between the lasing modes and the dislocation distribution, and can contribute to the development of low-threshold and high-efficiency GaN-based micro-lasers.

5.
Nano Converg ; 10(1): 37, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37561270

RESUMO

With a high specific capacity and low electrochemical potentials, metal anode batteries that use lithium, sodium and zinc metal anodes, have gained great research interest in recent years, as a potential candidate for high-energy-density storage systems. However, the uncontainable dendrite growth during the repeated charging process, deteriorates the battery performance, reduces the battery life and more importantly, raises safety concerns. With their unique properties, two-dimensional (2D) materials, can be used to modify various components in metal batteries, eventually mitigating the dendrite growth, enhancing the cycling stability and rate capability, thus leading to safe and robust metal anodes. In this paper, we review the recent advances of 2D materials and summarize current research progress of using 2D materials in the applications of (i) anode design, (ii) separator engineering, and (iii) electrolyte modifications by guiding metal ion nucleation, increasing ion conductivity, homogenizing the electric field and ion flux, and enhancing the mechanical strength for safe metal anodes. The 2D material modifications provide the ultimate solution for obtaining dendrite-free metal anodes, realizes the high energy storage application, and indicates the importance of 2D materials development. Finally, in-depth understandings of subsequent metal growth are lacking due to research limitations, while more advanced characterizations are welcome for investigating the metal deposition mechanism. The more facile and simplified preparation of 2D materials possess great prospects in high energy density metal anode batteries, and thus fulfils the development of EVs.

6.
Int J Biol Macromol ; 235: 123859, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36868334

RESUMO

The transmembrane prostate androgen-induced protein (TMEPAI) is known to be highly expressed in various types of cancer and promoted oncogenic abilities. However, the mechanisms whereby TMEPAI facilitates tumorigenesis are not fully understood. Here we reported that expression of TMEPAI activated the NF-κB signaling. TMEPAI showed direct interaction with NF-κB pathway inhibitory protein IκBα. Though ubiquitin ligase Nedd4 (neural precursor cell expressed, developmentally down-regulated 4) did not interact with IκBα directly, TMEPAI recruited Nedd4 for ubiquitination of IκBα, leading to IκBα degradation through the proteasomal and lysosomal pathway, and promoted activation of NF-κB signaling. Further study indicated NF-κB signaling is involved in TMEPAI-induced cell proliferation and tumor growth in immune deficient mice. This finding helps to further understand the mechanism of TMEPAI on tumorigenesis and suggests TMEPAI is potential target for cancer treatment.


Assuntos
Androgênios , NF-kappa B , Masculino , Camundongos , Animais , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , Androgênios/metabolismo , Próstata/metabolismo , Proteínas de Membrana/metabolismo , Transdução de Sinais , Fosforilação , Carcinogênese/metabolismo
7.
PLoS One ; 18(1): e0279097, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662763

RESUMO

Deeplabv3+ currently is the most representative semantic segmentation model. However, Deeplabv3+ tends to ignore targets of small size and usually fails to identify precise segmentation boundaries in the UAV remote sensing image segmentation task. To handle these problems, this paper proposes a semantic segmentation algorithm of UAV remote sensing images based on edge feature fusing and multi-level upsampling integrated with Deeplabv3+ (EMNet). EMNet uses MobileNetV2 as its backbone and adds an edge detection branch in the encoder to provide edge information for semantic segmentation. In the decoder, a multi-level upsampling method is designed to retain high-level semantic information (e.g., the target's location and boundary information). The experimental results show that the mIoU and mPA of EMNet improved over Deeplabv3+ by 7.11% and 6.93% on the dataset UAVid, and by 0.52% and 0.22% on the dataset ISPRS Vaihingen.


Assuntos
Tecnologia de Sensoriamento Remoto , Semântica , Algoritmos , Processamento de Imagem Assistida por Computador
8.
Eur J Pharmacol ; 934: 175307, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36191632

RESUMO

BACKGROUND & AIMS: Hypoxia inducible factor (HIF) is a hypoxia-associated transcription factor that has a protective role against hypoxia-induced damage. Prolyl hydroxylase-2 (PHD2) is a dioxygenase enzyme that specifically hydroxylates HIF targeting it for degradation, therefore, inhibition of the PHD2 enzyme activity acts to upregulate HIF function. This study was to identify novel PHD2 inhibitors. METHODS: An established fluorescence-based PHD2 activity assay was used for inhibitors screening. Western blot and quantitative real-time PCR was used to detect the protein and mRNA levels respectively. Further animal experiment was carried out. RESULTS: Caffeic acid was screened and identified as a novel PHD2 inhibitor. Caffeic acid treated PC12 and SH-SY5Y neuronal cell lines stabilized endogenous HIF-1α protein levels and consequently increased mRNA levels of its downstream regulated genes VEGF and EPO. Caffeic acid treatment reduced hypoxia-induced cell apoptosis and promoted HIF/BNIP3-mediated mitophagy. Moreover, animal studies indicated that caffeic acid increased the level of HIF-1α protein and mRNA levels of VEGF and EPO in the brain of mice exposed to hypoxia. Conventional brain injury markers including malondialdehyde, lactic acid and lactate dehydrogenase in the caffeic acid treated mice were shown to be reduced to the levels of the control group. CONCLUSIONS: This study suggests that caffeic acid inhibits PHD2 enzyme activity which then activates the hypoxia-associated transcription factor HIF leading to a neuroprotective effect against hypoxia.


Assuntos
Neuroblastoma , Fármacos Neuroprotetores , Inibidores de Prolil-Hidrolase , Humanos , Camundongos , Animais , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Inibidores de Prolil-Hidrolase/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Pró-Colágeno-Prolina Dioxigenase/genética , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Hipóxia/metabolismo , RNA Mensageiro/genética , Ácido Láctico , Malondialdeído , Lactato Desidrogenases , Fatores de Transcrição , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
9.
Small ; 18(37): e2107301, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35869035

RESUMO

GaN-based lateral Schottky barrier diodes (SBDs) have attracted great attention for high-power applications due to its combined high electron mobility and large critical breakdown field. However, the breakdown voltage (BV) of the SBDs are far from exploiting the material advantages of GaN at present, limiting the desire to use GaN for ultra-high voltage (UHV) applications. Then, a golden question is whether the excellent properties of GaN-based materials can be practically used in the UHV field? Here, UHV AlGaN/GaN SBDs are demonstrated on sapphire with a BV of 10.6 kV, a specific on-resistance (RON,SP ) of 25.8 mΩ cm2 , yielding a power figure-of-merit (P-FOM = BV2 /RON,SP ) of 4.35 GW cm-2 . These devices are designed with single channel and 85-µm anode-to-cathode spacing, without other additional electric field management, demonstrating its great potential for the UHV application in power electronics.

10.
Protein Expr Purif ; 194: 106073, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35192944

RESUMO

Prolyl hydroxylase-2 (PHD2) is a dioxygenase enzyme that specifically hydroxylates the hypoxia inducible factor (HIF) which then targets it for degradation in oxygenated cells. Inhibition of the activity of the PHD2 enzyme under hypoxic environmental conditions acts to upregulate HIF. Thus, PHD2 inhibitors may serve as a promising treatment for HIF-dependent diseases. In this study, recombinant PHD2 protein was successfully expressed using a baculovirus-insect cell expression secretory system. PHD2 was purified and in combination with bacterially expressed functional von Hippel Lindau protein-elongin B-elongin C (VBC) protein complex was used to successfully develop a fluorescence-based PHD2 activity assay. Myricetin was identified as a novel potent PHD2 inhibitor by high-throughput screening of a natural compound library. Further studies showed that treatment of human neuroblastoma SH-SY5Y cells with Myricetin increased HIF-1α protein levels. These results indicate that the insect cell expression system is capable of producing highly active recombinant PHD2 protein from which a fluorescence-based activity assay can be developed for high-throughput screening applications.


Assuntos
Dioxigenases , Prolina Dioxigenases do Fator Induzível por Hipóxia , Animais , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Insetos/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Prolil Hidroxilases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
11.
Phytother Res ; 35(11): 6441-6451, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34560814

RESUMO

Targeting the PD-1/PD-L1 immune checkpoints has achieved significant positive results in the treatment of multiple cancers. Quercetin is one of the most abundant dietary flavonoids found in various vegetables and fruits, and has a wide range of biological activities including immunomodulation. Here we report that quercetin dihydrate was screened and shown to inhibit the PD-1/PD-L1 interaction. Treatment with quercetin dihydrate promoted the killing activity of T cells on MDA-MB-231 and NCI-H460 cancer cells. Experiments using the xenograft mouse model showed that the growth rate of tumor volumes and masses in the quercetin dihydrate-treated mice were decreased. Immunohistochemistry of the tumors showed that CD8, GZMB, and IFN-γ were increased in the quercetin dihydrate-treated mice. These results suggest that quercetin dihydrate attenuates the inhibitory effect of PD-L1 on T cells by inhibiting the PD-1/PD-L1 interaction, which has an exciting potential to be used as a cancer chemopreventive agent.


Assuntos
Antígeno B7-H1 , Neoplasias , Animais , Linfócitos T CD8-Positivos , Camundongos , Receptor de Morte Celular Programada 1 , Quercetina/farmacologia , Linfócitos T
12.
Clin Cancer Res ; 27(19): 5376-5388, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34301753

RESUMO

PURPOSE: Efforts are required to improve the potency and durability of CD38- and BCMA-based immunotherapies in human multiple myeloma. We here delineated the molecular and cellular mechanisms underlying novel immunomodulatory effects triggered by BCMA pyrrolobenzodiazepine (PBD) antibody drug conjugate (ADC) MEDI2228 which can augment efficacy of these immunotherapies. EXPERIMENTAL DESIGN: MEDI2228-induced transcriptional and protein changes were investigated to define significantly impacted genes and signaling cascades in multiple myeloma cells. Mechanisms whereby MEDI2228 combination therapies can enhance cytotoxicity or overcome drug resistance in multiple myeloma cell lines and patient multiple myeloma cells were defined using in vitro models of tumor in the bone marrow (BM) microenvironment, as well as in human natural killer (NK)-reconstituted NOD/SCID gamma (NSG) mice bearing MM1S tumors. RESULTS: MEDI2228 enriched IFN I signaling and enhanced expression of IFN-stimulated genes in multiple myeloma cell lines following the induction of DNA damage-ATM/ATR-CHK1/2 pathways. It activated cGAS-STING-TBK1-IRF3 and STAT1-IRF1-signaling cascades and increased CD38 expression in multiple myeloma cells but did not increase CD38 expression in BCMA-negative NK effector cells. It overcame CD38 downregulation on multiple myeloma cells triggered by IL6 and patient BM stromal cell-culture supernatant via activation of STAT1-IRF1, even in immunomodulatory drug (IMiD)- and bortezomib-resistant multiple myeloma cells. In vitro and in vivo upregulation of NKG2D ligands and CD38 in MEDI2228-treated multiple myeloma cells was further associated with synergistic daratumumab (Dara) CD38 MoAb-triggered NK-mediated cytotoxicity of both cell lines and autologous drug-resistant patient multiple myeloma cells. CONCLUSIONS: These results provide the basis for clinical evaluation of combination MEDI2228 with Dara to further improve patient outcome in multiple myeloma.


Assuntos
Imunoconjugados , Mieloma Múltiplo , ADP-Ribosil Ciclase 1 , Animais , Anticorpos Monoclonais , Antígeno de Maturação de Linfócitos B , Linhagem Celular Tumoral , Humanos , Imunidade , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Glicoproteínas de Membrana , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Microambiente Tumoral
13.
Front Psychol ; 12: 657863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012414

RESUMO

This study aimed to explore the linking mechanisms and conditional processes underlying the relationship between proactive behavior and work-family conflict. Considering the conservation of resources theory, we argue that workplace anxiety mediates the relationship between proactive behavior and work-family conflict. Furthermore, we suggest that immediate supervisor perspective taking and employee emotional intelligence moderate this proposed indirect effect. Two-wave, multisource lagged data were collected from 450 employees of seven domestic Chinese firms to examine the hypothesized moderated mediation model. Our findings support the hypothesis that proactive behavior is positively related to work-family conflict and that workplace anxiety partially mediates this relationship. Immediate supervisor perspective taking moderates the positive association of proactive behavior with workplace anxiety and the indirect relationship between proactive behavior and work-family conflict through workplace anxiety. Emotional intelligence moderates the positive association of proactive behavior with workplace anxiety and the indirect relationship between proactive behavior and work-family conflict through workplace anxiety. The results deepen our theoretical understanding of the consequences of proactivity by demonstrating the positive associations between proactive behavior and work-family conflict. The current study also contributes to the literature by identifying workplace anxiety as a mediating mechanism explaining the relationship between proactivity and work-family conflict. Furthermore, supervisor perspective taking and employee emotional intelligence moderate the above mediating effect.

14.
Opt Express ; 29(9): 13469-13485, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33985079

RESUMO

Many illumination applications require redistributing the irradiance distributions of LED sources with large ray bending. The problem becomes even more challenging for a compact design where the LED size is no longer ignorable. We tackle this problem by simultaneously designing two freeform optical surfaces. An iterative wavefront tailoring (IWT) method is adapted for obtaining the entrance and exit base freeform surfaces with a predefined ray bending regulation under stereographic coordinates (u, v). The simulated annealing (SA) algorithm is employed for deforming the two base freeform surfaces using the 'uv' polynomials with the purpose of minimizing the relative root-mean-square deviation (RRMSD) between the simulated irradiance distribution and the prescribed one. The optimizations are implemented in an automated workflow which links the optimization engine, 3D modeling software and ray tracing software. The effectiveness of the proposed method is illustrated by designing several double-freeform-surface lenses (central heights: 10 mm) with different ray bending regulated base surfaces and 10-th order uv polynomial departures for generating 500 × 200 mm2 uniform irradiance distributions at a distance of 100 mm from 2 × 2 mm2 and 3 × 3 mm2 sources, respectively.

15.
Food Funct ; 12(7): 2914-2924, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33720241

RESUMO

Telomere shortening is one of the main causes of cellular senescence. Caffeine is a natural stimulant most commonly found in coffee and tea. In this study, caffeine was found to promote the expression of telomerase reverse transcriptase (TERT) at both mRNA and protein levels, and consequently extended the telomere length and prevented cellular senescence. Knockdown of TERT eliminated the effect of caffeine on telomere elongation. Moreover, animal studies indicated that caffeine promoted the expression of TERT and extended the telomere length in the thymus and spleen of mice treated with caffeine for a long period of eight months. In addition, caffeine restored the decline of organ index and improved the histological structural change of the thymus, spleen and liver of mice due to aging. These results suggest that caffeine promotes the expression of TERT to delay cellular senescence and aging, which help to understand the mechanism for the beneficial effects of caffeine containing foods on health.


Assuntos
Cafeína/farmacologia , Envelhecimento da Pele , Telomerase/efeitos dos fármacos , Animais , Cafeína/administração & dosagem , Senescência Celular/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Telomerase/genética , Encurtamento do Telômero/efeitos dos fármacos
16.
Biochem Cell Biol ; 99(5): 519-526, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33560918

RESUMO

Autophagy plays a key role in the metabolism of macromolecules via the degradative abilities of the lysosome. Transcription factor EB (TFEB) regulates autophagosome biogenesis and lysosome function, and promoting TFEB activity has emerged as a potential strategy for the treatment of metabolic disorders. Herein, we report that cetrimonium bromide (CTAB; a quaternary ammonium compound) promotes autophagy and lysosomal biogenesis by inducing the nuclear translocation of TFEB in hepatic cells. Knockdown of TFEB mediated by short hairpin RNA inhibits CTAB-induced autophagy and lysosomal biogenesis. Mechanistically, CTAB treatment inhibits the Akt-mTORC1 signaling pathway. Moreover, CTAB treatment significantly increases lipid metabolism in both palmitate- and oleate-treated HepG2 cells, and this increase was attenuated by knockdown of TFEB. Collectively, our results indicate that CTAB activates the autophagosome-lysosome pathway via inducing the nuclear translocation of TFEB by inhibiting the mTORC1 signaling pathway. These results add to the collective understanding of TFEB function and provide new insights into CTAB-mediated lipid metabolism.


Assuntos
Autofagossomos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Cetrimônio/farmacologia , Hepatócitos/metabolismo , Lisossomos/metabolismo , Autofagossomos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/antagonistas & inibidores , Células Cultivadas , Cetrimônio/antagonistas & inibidores , Hepatócitos/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , RNA Interferente Pequeno/farmacologia
17.
Invest New Drugs ; 39(2): 337-347, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32978718

RESUMO

Legumain is a newly discovered lysosomal cysteine protease that can cleave asparagine bonds and plays crucial roles in regulating immunity and cancer metastasis. Legumain has been shown to be highly expressed in various solid tumors, within the tumor microenvironment and its levels are directly related to tumor metastasis and poor prognosis. Therefore, legumain presents as a potential cancer therapeutic drug target. In this study, we have identified esomeprazole and omeprazole as novel legumain small molecule inhibitors by screening an FDA approved-drug library. These compounds inhibited enzyme activity of both recombinant and endogenous legumain proteins with esomeprazole displaying the highest inhibitory effect. Further molecular docking analysis also indicated that esomeprazole, the S- form of omeprazole had the most stable binding to legumain protein compared to R-omeprazole. Transwell assay data showed that esomeprazole and omeprazole reduced MDA-MB-231 breast cancer cell invasion without effecting cell viability. Moreover, an in vivo orthotopic transplantation nude mouse model study showed that esomeprazole reduced lung metastasis of MDA-MB-231 breast cancer cells. These results indicated that esomeprazole has the exciting potential to be used in anti-cancer therapy by preventing cancer metastasis via the inhibition of legumain enzyme activity. Graphical abstract.


Assuntos
Antiulcerosos/farmacologia , Cisteína Endopeptidases/efeitos dos fármacos , Esomeprazol/farmacologia , Omeprazol/farmacologia , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Cisteína Proteases/efeitos dos fármacos , Esomeprazol/química , Feminino , Humanos , Neoplasias Pulmonares/patologia , Lisossomos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Omeprazol/química , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Int J Biol Macromol ; 166: 884-892, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33157139

RESUMO

Alpha-fetoprotein (AFP) is one of the most important biomarkers associated with primary liver cancer, and the main approaches for diagnosis are based on immunoassay. Affibody is a 58 amino acids peptide derived from the Z domain of staphylococcal protein A and generally applied in imaging diagnosis, clinical therapeutics and biotechnology research. The aim of this study was therefore to develop a novel affibody-based ELISA for detection of AFP. After three rounds of biopanning, six AFP-binding affibody peptides were selected using phage display technology, among them affibody ZAFPD2 showed high and specific binding affinity to AFP. An affibody dimer of ZAFPD2 was created, named (ZAFP D2)2, expressed in E.coli and the purified (ZAFP D2)2 recombinant protein showed higher binding affinity to AFP, as well as high thermal stability. A novel affibody-based two-site ELISA method using ZAFPD2 or (ZAFP D2)2 and polyclonal antibody to detect AFP was developed, the detection limit of the immunoassay using (ZAFP D2)2 was 2 ng mL-1 that was 4 times lower than ZAFPD2, which meets the requirements for practical application. Therefore, this concept of affibody-based ELISA may provide a new method for the detection of various cancer biomarkers.


Assuntos
Anticorpos/imunologia , Biblioteca de Peptídeos , alfa-Fetoproteínas/imunologia , Anticorpos/química , Sítios de Ligação , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Ligação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , alfa-Fetoproteínas/análise , alfa-Fetoproteínas/metabolismo
19.
Leukemia ; 35(3): 752-763, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32632095

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy remains limited to select centers that can carefully monitor adverse events. To broaden use of CAR T cells in community clinics and in a frontline setting, we developed a novel CD8+ CAR T-cell product, Descartes-08, with predictable pharmacokinetics for treatment of multiple myeloma. Descartes-08 is engineered by mRNA transfection to express anti-BCMA CAR for a defined length of time. Descartes-08 expresses anti-BCMA CAR for 1 week, limiting risk of uncontrolled proliferation; produce inflammatory cytokines in response to myeloma target cells; and are highly cytolytic against myeloma cells regardless of the presence of myeloma-protecting bone marrow stromal cells, exogenous a proliferation-inducing ligand, or drug resistance including IMiDs. The magnitude of cytolysis correlates with anti-BCMA CAR expression duration, indicating a temporal limit in activity. In the mouse model of aggressive disseminated human myeloma, Descartes-08 induces BCMA CAR-specific myeloma growth inhibition and significantly prolongs host survival (p < 0.0001). These preclinical data, coupled with an ongoing clinical trial of Descartes-08 in relapsed/refractory myeloma (NCT03448978) showing preliminary durable responses and a favorable therapeutic index, have provided the framework for a recently initiated trial of an optimized/humanized version of Descartes-08 (i.e., Descartes-11) in newly diagnosed myeloma patients with residual disease after induction therapy.


Assuntos
Antígeno de Maturação de Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunoterapia Adotiva/métodos , Mieloma Múltiplo/terapia , RNA Mensageiro/genética , Receptores de Antígenos Quiméricos/imunologia , Animais , Apoptose , Antígeno de Maturação de Linfócitos B/genética , Proliferação de Células , Avaliação Pré-Clínica de Medicamentos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Protein Expr Purif ; 178: 105783, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33122138

RESUMO

Natural killer (NK) cells are potent cytotoxic effector cells of the innate immune system and play an important role in tumor immunosurveillance and control. NKG2D is an activating receptor of NK cells. The NKG2D receptor-ligand system has contributed to immune cells recognizing tumor cells and the tumor microenvironment. In order to stretch the application of NK cells on adoptive immunotherapy for B-cell malignancies, we designed and produced a novel bispecific ULBP1×CD19-scFv fusion protein, in which the extracellular domain of NKG2D ligand ULBP1 was fused to a single chain variable fragment (scFv) of anti-CD19. The vector expressing ULBP1×CD19-scFv protein was constructed and expressed in Pichia pastoris. Effects of medium composition, concentration of methanol as the inducer, induction time and broth content in shake flask on the expression of the recombinant protein were investigated. The results showed that the optimized conditions for ULBP1×CD19-scFv expression were 1% methanol induction for 96 h with 15% broth content. The secreted recombinant protein was purified using ammonium sulfate fractionation and Ni-NTA affinity chromatography and the purity is about 93%. The cytotoxicity of NK92-MI cells against CD19+ Raji cells was enhanced in the presence of purified ULBP1×CD19-scFv protein. These results indicated that ULBP1 could be used as an activating element of bispecific killer engagers (BiKEs) and Pichia pastoris yeast might be an alternative expression host for BiKEs production.


Assuntos
Anticorpos Biespecíficos , Antígenos CD19/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Anticorpos de Cadeia Única , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/isolamento & purificação , Células Hep G2 , Humanos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/antagonistas & inibidores , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Proteínas Recombinantes de Fusão , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/isolamento & purificação
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