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2.
Nano Converg ; 10(1): 37, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37561270

RESUMEN

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.

3.
Nanomaterials (Basel) ; 13(15)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37570546

RESUMEN

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.

4.
Int J Biol Macromol ; 235: 123859, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-36868334

RESUMEN

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.


Asunto(s)
Andrógenos , FN-kappa B , Masculino , Ratones , Animales , FN-kappa B/metabolismo , Inhibidor NF-kappaB alfa/metabolismo , Andrógenos/metabolismo , Próstata/metabolismo , Proteínas de la Membrana/metabolismo , Transducción de Señal , Fosforilación , Carcinogénesis/metabolismo
5.
PLoS One ; 18(1): e0279097, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36662763

RESUMEN

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.


Asunto(s)
Tecnología de Sensores Remotos , Semántica , Algoritmos , Procesamiento de Imagen Asistido por Computador
6.
Eur J Pharmacol ; 934: 175307, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36191632

RESUMEN

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.


Asunto(s)
Neuroblastoma , Fármacos Neuroprotectores , Inhibidores de Prolil-Hidroxilasa , Humanos , Ratones , Animales , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Inhibidores de Prolil-Hidroxilasa/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Procolágeno-Prolina Dioxigenasa/genética , Procolágeno-Prolina Dioxigenasa/metabolismo , Hipoxia/metabolismo , ARN Mensajero/genética , Ácido Láctico , Malondialdehído , Lactato Deshidrogenasas , Factores de Transcripción , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética
7.
Small ; 18(37): e2107301, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35869035

RESUMEN

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.

8.
Protein Expr Purif ; 194: 106073, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35192944

RESUMEN

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.


Asunto(s)
Dioxigenasas , Prolina Dioxigenasas del Factor Inducible por Hipoxia , Animales , Humanos , Prolina Dioxigenasas del Factor Inducible por Hipoxia/genética , Insectos/metabolismo , Procolágeno-Prolina Dioxigenasa/metabolismo , Prolil Hidroxilasas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología
9.
Phytother Res ; 35(11): 6441-6451, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34560814

RESUMEN

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.


Asunto(s)
Antígeno B7-H1 , Neoplasias , Animales , Linfocitos T CD8-positivos , Ratones , Receptor de Muerte Celular Programada 1 , Quercetina/farmacología , Linfocitos T
10.
Clin Cancer Res ; 27(19): 5376-5388, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34301753

RESUMEN

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.


Asunto(s)
Inmunoconjugados , Mieloma Múltiple , ADP-Ribosil Ciclasa 1 , Animales , Anticuerpos Monoclonales , Antígeno de Maduración de Linfocitos B , Línea Celular Tumoral , Humanos , Inmunidad , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Glicoproteínas de Membrana , Ratones , Ratones Endogámicos NOD , Ratones SCID , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/patología , Microambiente Tumoral
11.
Opt Express ; 29(9): 13469-13485, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33985079

RESUMEN

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.

12.
Front Psychol ; 12: 657863, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34012414

RESUMEN

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.

13.
Food Funct ; 12(7): 2914-2924, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33720241

RESUMEN

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.


Asunto(s)
Cafeína/farmacología , Envejecimiento de la Piel , Telomerasa/efectos de los fármacos , Animales , Cafeína/administración & dosificación , Senescencia Celular/efectos de los fármacos , Ratones , Ratones Endogámicos , Telomerasa/genética , Acortamiento del Telómero/efectos de los fármacos
14.
Biochem Cell Biol ; 99(5): 519-526, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33560918

RESUMEN

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.


Asunto(s)
Autofagosomas/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Cetrimonio/farmacología , Hepatocitos/metabolismo , Lisosomas/metabolismo , Autofagosomas/efectos de los fármacos , Autofagia/efectos de los fármacos , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/antagonistas & inhibidores , Células Cultivadas , Cetrimonio/antagonistas & inhibidores , Hepatocitos/efectos de los fármacos , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Lisosomas/efectos de los fármacos , ARN Interferente Pequeño/farmacología
15.
Invest New Drugs ; 39(2): 337-347, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32978718

RESUMEN

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.


Asunto(s)
Antiulcerosos/farmacología , Cisteína Endopeptidasas/efectos de los fármacos , Esomeprazol/farmacología , Omeprazol/farmacología , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular , Proteasas de Cisteína/efectos de los fármacos , Esomeprazol/química , Femenino , Humanos , Neoplasias Pulmonares/patología , Lisosomas/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Omeprazol/química , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Leukemia ; 35(3): 752-763, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32632095

RESUMEN

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.


Asunto(s)
Antígeno de Maduración de Linfocitos B/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunoterapia Adoptiva/métodos , Mieloma Múltiple/terapia , ARN Mensajero/genética , Receptores Quiméricos de Antígenos/inmunología , Animales , Apoptosis , Antígeno de Maduración de Linfocitos B/genética , Proliferación Celular , Evaluación Preclínica de Medicamentos , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Mieloma Múltiple/inmunología , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Protein Expr Purif ; 178: 105783, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33122138

RESUMEN

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.


Asunto(s)
Anticuerpos Biespecíficos , Antígenos CD19/inmunología , Células Asesinas Naturales/inmunología , Activación de Linfocitos , Subfamilia K de Receptores Similares a Lectina de Células NK , Anticuerpos de Cadena Única , Anticuerpos Biespecíficos/química , Anticuerpos Biespecíficos/inmunología , Anticuerpos Biespecíficos/aislamiento & purificación , Células Hep G2 , Humanos , Subfamilia K de Receptores Similares a Lectina de Células NK/antagonistas & inhibidores , Subfamilia K de Receptores Similares a Lectina de Células NK/inmunología , Proteínas Recombinantes de Fusión , Anticuerpos de Cadena Única/química , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/aislamiento & purificación
18.
Int J Biol Macromol ; 166: 884-892, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33157139

RESUMEN

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.


Asunto(s)
Anticuerpos/inmunología , Biblioteca de Péptidos , alfa-Fetoproteínas/inmunología , Anticuerpos/química , Sitios de Unión , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Unión Proteica , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/metabolismo , alfa-Fetoproteínas/análisis , alfa-Fetoproteínas/metabolismo
19.
Blood Cancer J ; 10(11): 110, 2020 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-33149123

RESUMEN

Therapeutically targeting CD138, a define multiple myeloma (MM) antigen, is not yet approved for patients. We here developed and determined the preclinical efficacy of VIS832, a novel therapeutic monoclonal antibody (MoAb) with differentiated CD138 target binding to BB4 that is anti-CD138 MoAb scaffold for indatuximab ravtansine (BT062). VIS832 demonstrated enhanced CD138-binding avidity and significantly improved potency to kill MM cell lines and autologous patient MM cells regardless of resistance to current standard-of-care therapies, via robust antibody-dependent cellular cytotoxicity and phagocytosis mediated by NK and macrophage effector cells, respectively. Specifically, CD38-targeting daratumumab-resistant MM cells were highly susceptible to VIS832 which, unlike daratumumab, spares NK cells. Superior maximal cytolysis of VIS832 vs. daratumumab corresponded to higher CD138 vs. CD38 levels in MM cells. Furthermore, VIS832 acted synergistically with lenalidomide or bortezomib to deplete MM cells. Importantly, VIS832 at a sub-optimal dose inhibited disseminated MM1S tumors in vivo as monotherapy (P < 0.0001), and rapidly eradicated myeloma burden in all mice concomitantly receiving bortezomib, with 100% host survival. Taken together, these data strongly support clinical development of VIS832, alone and in combination, for the therapeutic treatment of MM in relapsed and refractory patients while pointing to its potential therapeutic use earlier in disease intervention.


Asunto(s)
Antineoplásicos Inmunológicos/farmacología , Bortezomib/farmacología , Inmunoconjugados/farmacología , Mieloma Múltiple/tratamiento farmacológico , Proteínas de Neoplasias/antagonistas & inhibidores , Sindecano-1/antagonistas & inhibidores , Animales , Antineoplásicos Inmunológicos/inmunología , Bortezomib/agonistas , Línea Celular Tumoral , Sinergismo Farmacológico , Humanos , Maitansina/agonistas , Maitansina/análogos & derivados , Maitansina/farmacología , Ratones , Ratones SCID , Mieloma Múltiple/inmunología , Mieloma Múltiple/patología , Proteínas de Neoplasias/inmunología , Sindecano-1/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Blood Adv ; 4(17): 4195-4207, 2020 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-32898244

RESUMEN

We investigated here the novel immunomodulation and anti-multiple myeloma (MM) function of T cells engaged by the bispecific T-cell engager molecule AMG 701, and further examined the impact of AMG 701 in combination with immunomodulatory drugs (IMiDs; lenalidomide and pomalidomide). AMG 701 potently induced T-cell-dependent cellular cytotoxicity (TDCC) against MM cells expressing B-cell maturation antigen, including autologous cells from patients with relapsed and refractory MM (RRMM) (half maximal effective concentration, <46.6 pM). Besides inducing T-cell proliferation and cytolytic activity, AMG 701 also promoted differentiation of patient T cells to central memory, effector memory, and stem cell-like memory (scm) phenotypes, more so in CD8 vs CD4 T subsets, resulting in increased CD8/CD4 ratios in 7-day ex vivo cocultures. IMiDs and AMG 701 synergistically induced TDCC against MM cell lines and autologous RRMM patient cells, even in the presence of immunosuppressive bone marrow stromal cells or osteoclasts. IMiDs further upregulated AMG 701-induced patient T-cell differentiation toward memory phenotypes, associated with increased CD8/CD4 ratios, increased Tscm, and decreased interleukin 10-positive T and T regulatory cells (CD25highFOXP3high), which may downregulate T effector cells. Importantly, the combination of AMG 701 with lenalidomide induced sustained inhibition of MM cell growth in SCID mice reconstituted with human T cells; tumor regrowth was eventually observed in cohorts treated with either agent alone (P < .001). These results strongly support AMG 701 clinical studies as monotherapy in patients with RRMM (NCT03287908) and the combination with IMiDs to improve patient outcomes in MM.


Asunto(s)
Mieloma Múltiple , Preparaciones Farmacéuticas , Animales , Humanos , Inmunomodulación , Lenalidomida , Ratones , Ratones SCID , Mieloma Múltiple/tratamiento farmacológico , Talidomida/análogos & derivados
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