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T cell responses are regulated by co-stimulatory and inhibitory receptors along with T cell receptor- and cytokine-mediated signals. CD51 is a transmembrane glycoprotein of the integrin family that plays a role in cell adhesion, migration, tumorigenesis, and other cellular functions. In this study, we aimed to investigate the expression and function of CD51 on CD8 T cells. Upon in vitro T cell activation, CD51 expression was delayed but subsequently was upregulated in CD8 T cells upon cell division. Furthermore, CD51 was highly expressed in exhausted CD8 T cells in chronic LCMV infection, B16F10 melanoma, and CT26 colon carcinoma, and its expression level increased as cells became more differentiated. Using CRISPR-mediated knockdown, we found that the absence of CD51 led to a lower number of virus-specific CD8 T cells upon chronic lymphocytic choriomeningitis virus (LCMV) infection, although their granzyme B expression and cytokine production were maintained. Blocking CD51 also inhibited the in vitro proliferation of CD8 T cells. These results suggest that CD51 plays an important role in the early expansion of CD8 T cells and may have potential as an immunomodulatory target.
Assuntos
Coriomeningite Linfocítica , Animais , Camundongos , Linfócitos T CD8-Positivos , Citocinas/metabolismo , Ativação Linfocitária , Coriomeningite Linfocítica/metabolismo , Coriomeningite Linfocítica/patologia , Vírus da Coriomeningite Linfocítica , Camundongos Endogâmicos C57BL , Integrina alfaV/imunologiaRESUMO
This study was carried out to investigate the impact the quality of the drill bits has on the machining behavior of additive manufacturing (AM) and powder metallurgy (PM) titanium alloys. Therefore, commercially available drill bits which typically reflect two extremes of drill bit quality were selected. The performance of coated carbide twist drills, typically recommended for the drilling of wrought titanium alloys was compared with that of high-speed steel (HSS) drills. The average torque value, specific cutting energy (SCE), and tool wear were used to evaluate the drilling performance of AM and PM titanium alloys. The results of drilling tests revealed the application of the coated carbide drill resulted in lower torque and SCE values, less flank wear, and lower build-up-edge (BUE) compared with the uncoated HSS drill bits for AM fabricated titanium alloys. However, the carbide drill appeared to offer negligible improvement over the uncoated HSS drill when employed with the PM fabricated titanium alloy. In spite of the improvement in the drilling performance offered by the carbide drills for the AM titanium alloy, TiB intermetallic particles (part of the AM titanium microstructure) contributed to the damage of the coated carbide drill which would limit the drill lifetime.
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Bacterial infection and blockage are severe problems for polyurethane (PU) catheters and there is an urgent demand for surface-functionalized polyurethane. Herein, a cationic alternating copolymer comprising allyl-substituted ornithine and glycine (allyl-substituted poly(Orn-alter-Gly)) with abundant carbon-carbon double bond functional groups (CâC) is designed. Polyurethane is prepared with a large quantity of CâC groups (PU-D), and different amounts of allyl-substituted poly(Orn-alter-Gly) are grafted onto the PU-D surface (PU-D-2%AMPs and PU-D-20%AMPs) via the CâC functional groups. The chemical structures of the allyl-substituted poly(Orn-alter-Gly) and polyurethane samples (PU, PU-D, PU-D-2%AMPs, and PU-D-20%AMPs) are characterized and the results reveal that allyl-substituted poly(Orn-alter-Gly) is decorated on the polyurethane. PU-D-20%AMPs shows excellent antibacterial activity against Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus because of the high surface potential caused by cationic allyl-substituted poly(Orn-alter-Gly), and it also exhibits excellent long-term antibacterial activity and antibiofilm properties. PU-D-20%AMPs also has excellent antifouling properties because the cationic copolymer is fixed at multiple reactive sites, thus avoiding the formation of movable long chain brush. A strong surface hydration barrier is also formed to prevent adsorption of proteins and ions, and in vivo experiments reveal excellent biocompatibility. This flexible strategy to prepare dual-functional polyurethane surfaces with antibacterial and antifouling properties has large potential in biomedical implants.
Assuntos
Incrustação Biológica , Poliuretanos , Antibacterianos/toxicidade , Incrustação Biológica/prevenção & controle , Peptídeos/farmacologia , Poliuretanos/toxicidade , Staphylococcus aureus , Propriedades de SuperfícieRESUMO
Development of proteolysis targeting chimeras (PROTACs) is emerging as a promising strategy for targeted protein degradation. However, the drug development using the heterobifunctional PROTAC molecules is generally limited by poor membrane permeability, low in vivo efficacy and indiscriminate distribution. Herein an aptamer-PROTAC conjugation approach was developed as a novel strategy to improve the tumor-specific targeting ability and in vivo antitumor potency of conventional PROTACs. As proof of concept, the first aptamer-PROTAC conjugate (APC) was designed by conjugating a BET-targeting PROTAC to the nucleic acid aptamer AS1411 (AS) via a cleavable linker. Compared with the unmodified BET PROTAC, the designed molecule (APR) showed improved tumor targeting ability in a MCF-7 xenograft model, leading to enhanced in vivo BET degradation and antitumor potency and decreased toxicity. Thus, the APC strategy may pave the way for the design of tumor-specific targeting PROTACs and have broad applications in the development of PROTAC-based drugs.
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Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Oligodesoxirribonucleotídeos/uso terapêutico , Proteólise/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Aptâmeros de Nucleotídeos/síntese química , Aptâmeros de Nucleotídeos/toxicidade , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Dissulfetos/síntese química , Dissulfetos/uso terapêutico , Dissulfetos/toxicidade , Compostos Heterocíclicos com 3 Anéis/síntese química , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/toxicidade , Humanos , Camundongos , Oligodesoxirribonucleotídeos/síntese química , Oligodesoxirribonucleotídeos/toxicidade , Estudo de Prova de Conceito , Pirrolidinas/síntese química , Pirrolidinas/uso terapêutico , Pirrolidinas/toxicidade , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
An uncooled infrared focal plane array (FPA) for a multiband optical imaging system monitoring small gas leakages is low in cost but limited by its frame rate and sensitivity. We propose the concept of Archimedean spiral push-broom filtering (ASPBF), where the trajectory of an Archimedean spiral over the FPA is approximated as a straight line. The ASPBF precisely matches the electronic pulse scanning of the uncooled infrared FPA row by row to improve the frame rate. We applied differential imaging to promote gas detection sensitivity. Prototype can detect 11 ml/min of ethylene gas at ΔT = 3 °C with frame rate of 8 fps.
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Proteolysis targeting chimeras (PROTACs) technology is rapidly developed as a novel and selective medicinal strategy for the degradation of cellular proteins in cancer therapy. However, the applications of PROTACs as heterobifunctional molecules are largely limited by high molecular weight, low bioavailability, poor permeability, insufficient targeting, and low efficacy in vivo. Herein, self-assembling micelles of FA-PEG-PROTAC are designed for cancer cell selective targeting and reductive-response proteolysis in tumor-bearing mice. FA-PEG-PROTAC is prepared by conjugating folic acid (FA)-PEG with EGFR-targeting PROTAC via a disulfide bond. The FA-PEG-PROTAC micelles, formed by self-assembling, are demonstrated to significantly improve tumor targeting efficacy and exhibit excellent anti-tumor efficacy in the mouse xenograft model compared to the traditional PROTACs. The strategy of applying self-assembled FA-PEG-PROTAC micelles in tumor therapy can not only improve targeted proteolysis efficiency but also broaden applications in the development of PROTAC-based drugs.
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Ácido Fólico , Micelas , Polietilenoglicóis , Proteólise , Animais , Ácido Fólico/química , Ácido Fólico/análogos & derivados , Polietilenoglicóis/química , Proteólise/efeitos dos fármacos , Humanos , Camundongos , Linhagem Celular Tumoral , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C , Receptores ErbB/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Sistemas de Liberação de Medicamentos/métodosRESUMO
Tea cream formed in hot and strong tea infusion while cooling deteriorates quality and health benefits of tea. However, the interactions among temporal contributors during dynamic formation of tea cream are still elusive. Here, by deletional recombination experiments and molecular dynamics simulation, it was found that proteins, caffeine (CAF), and phenolics played a dominant role throughout the cream formation, and the contribution of amino acids was highlighted in the early stage. Furthermore, CAF was prominent due to its extensive binding capacity and the filling complex voids property, and caffeine-theaflavins (TFs) complexation may be the core skeleton of the growing particles in black tea infusion. In addition to TFs, the unidentified phenolic oxidation-derived products (PODP) were confirmed to contribute greatly to the cream formation.
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Cafeína , Camellia sinensis , Catequina , Simulação de Dinâmica Molecular , Chá , Chá/química , Cafeína/química , Cafeína/metabolismo , Camellia sinensis/química , Camellia sinensis/metabolismo , Camellia sinensis/crescimento & desenvolvimento , Catequina/química , Catequina/metabolismo , Biflavonoides/química , Biflavonoides/metabolismo , Fenóis/química , Fenóis/metabolismo , Manipulação de Alimentos , Temperatura AltaRESUMO
Graft-versus-host disease (GvHD) is a severe complication of hematopoietic stem cell transplantation driven by activated allogeneic T cells. Here, we identify a distinct subset of T cell factor-1 (TCF1)+ CD8+ T cells in mouse allogeneic and xenogeneic transplant models of acute GvHD. These TCF1+ cells exhibit distinct characteristics compared to TCF1- cells, including lower expression of inhibitory receptors and higher expression of costimulatory molecules. Notably, the TCF1+ subset displays exclusive proliferative potential and could differentiate into TCF1- effector cells upon antigenic stimulation. Pathway analyses support the role of TCF1+ and TCF1- subsets as resource cells and effector cells, respectively. Furthermore, the TCF1+ CD8+ T cell subset is primarily present in the spleen and exhibits a resident phenotype. These findings provide insight into the differentiation of allogeneic and xenogeneic CD8+ T cells and have implications for the development of immunotherapeutic strategies targeting acute GvHD.
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Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Camundongos , Linfócitos T CD8-Positivos , Diferenciação Celular , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Fenótipo , HumanosRESUMO
In chronic infections and cancer, exhausted CD8 T cells exhibit heterogeneous subpopulations. TCF1+PD-1+ progenitor exhausted CD8 T cells (Tpex) can self-renew and give rise to Tim-3+PD-1+ terminally differentiated CD8 T cells that retain their effector functions. Tpex cells are thus essential to maintaining a pool of antigen-specific CD8 T cells during persistent antigenic stimulation, and only they respond to PD-1-targeted therapy. Despite their potential as a crucial therapeutic target for immune interventions, the mechanisms controlling the maintenance of virus-specific Tpex cells remain to be determined. We observed approximately 10-fold fewer Tpex cells in the spleens of mice chronically infected with lymphocytic choriomeningitis virus (LCMV) one-year post-infection (p.i.) than at three months p.i. Similar to memory CD8 T cells, Tpex cells have been found to undergo self-renewal in the lymphoid organs, prominently the bone marrow, during chronic LCMV infection. Furthermore, ex vivo treatment with IL-15 preferentially induced the proliferation of Tpex cells rather than the terminally differentiated subsets. Interestingly, single-cell RNA sequencing analysis of LCMV-specific exhausted CD8 T cells after ex vivo IL-15 treatment compared with those before treatment revealed increased expression of ribosome-related genes and decreased expression of genes associated with the TCR signaling pathway and apoptosis in both Tpex and Ttex subsets. The exogenous administration of IL-15 to chronically LCMV-infected mice also significantly increased self-renewal of Tpex cells in the spleen and bone marrow. In addition, we assessed the responsiveness of CD8 tumor-infiltrating lymphocytes (TILs) from renal cell carcinoma patients to IL-15. Similar to the data we obtained from chronic viral infection in mice, the expansion of the Tpex subset of PD-1+ CD8 TILs upon ex vivo IL-15 treatment was significantly higher than that of the terminally differentiated subset. These results show that IL-15 could promote self-renewal of Tpex cells, which has important therapeutic implications.
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Interleucina-15 , Coriomeningite Linfocítica , Receptor de Morte Celular Programada 1 , Animais , Camundongos , Linfócitos T CD8-Positivos , Interleucina-15/farmacologia , Vírus da Coriomeningite Linfocítica , Receptor de Morte Celular Programada 1/metabolismo , Transdução de SinaisRESUMO
Crop rotation is a typical agronomic practice to mitigate soil deterioration caused by continuous cropping. However, the mechanisms of soil biotic and abiotic factors in response to different cropping patterns in acidic and polyphenol-rich tea nurseries remain unclear. In this study, the composition and function of microbial communities were comparatively investigated in soils of tea seedlings continuously planted for 2 years (AC: autumn-cutting; SC: summer-cutting) and in soils rotation with strawberries alternately for 3 years (AR: autumn-cutting). The results showed that AR significantly improved the survival of tea seedlings but greatly reduced the contents of soil polyphenols. The lower soil polyphenol levels in AR were associated with the decline of nutrients (SOC, TN, Olsen-P) availability, which stimulates the proliferation of nutrient cycling-related bacteria and mixed-trophic fungi, endophytic fungi and ectomycorrhizal fungi, thus further satisfying the nutrient requirements of tea seedlings. Moreover, lower levels of polyphenols facilitated the growth of plant beneficial microorganisms (Bacillus, Mortierella, etc.) and suppressed pathogenic fungi (Pseudopestalotiopsis, etc.), creating a more balanced microbial community that is beneficial to plant health. Our study broadens the understanding of the ecological role of plant secondary metabolites and provides new insights into the sustainability of tea breeding.
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OBJECTIVE: To compare the efficacy on insomnia between Fang 's scalp acupuncture combined with conventional acupuncture and the simple conventional acupuncture. METHODS: A total of 66 patients with insomnia were randomly divided into an observation group (33 cases, 1 case dropped off) and a control group (33 cases, 2 cases dropped off). In the control group, the routine acupuncture therapy was applied to Shenmen (HT 7), Baihui (GV 20), Zhaohai (KI 6) and Sanyinjiao (SP 6), etc. Based on the treatment as the control group, Fang's scalp acupuncture therapy was supplemented at fuxiang tou, fuzang shangjiao, fuzang zhongjiao, siwei, etc. At these scalp points, the needles were inserted perpendicularly with flying needling technique and manipulated with trembling one. In either group, the treatment was given once daily, continuously for 2 weeks. Before and after treatment, separately, the score of Pittsburgh sleep quality index (PSQI) and the score of Chinese perceived stress scale (CPSS) were observed, as well as the parameters monitored by polysomnography, i.g. total sleep time (TST), sleep onset latency (SOL), wakefulness after the sleep onset (WASO), sleep efficiency (SE), the percentages of the time of rapid eye movement sleep phase (REM) and non-rapid eye movement sleep phase 1, 2, 3 and 4 in TST (REM%, N1%, N2%, N3%). The efficacy was compared between two groups. RESULTS: After treatment, the scores of each factor and the total scores of PSQI, as well as CPSS scores were all lower than those before treatment in the two groups (P<0.01, P<0.05); except the score for sleep quality, the score of each factor and the total score of PSQI, as well as CPSS score in the observation group were lower than those in the control group (P<0.01, P<0.05). After treatment, TST, SE%, REM% and N3% were increased and SOL, WASO, N1% were decreased as compared with before treatment in the two groups (P<0.01, P<0.05), and N2% in the observation group was decreased (P<0.01); SE%, REM% and N3% in the observation group were higher than the control group (P<0.05) and N1% and N2% were lower than the control group (P<0.05). The total effective rate was 93.8% (30/32) in the observation group, higher than 87.1% (27/31) in the control group (P<0.05). CONCLUSION: Fang 's scalp acupuncture, on the base of routine acupuncture, obviously improves the sleep quality and perceived stress and adjusts the sleep structure in the patients with insomnia.
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Terapia por Acupuntura , Distúrbios do Início e da Manutenção do Sono , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Humanos , Couro Cabeludo , Sono , Distúrbios do Início e da Manutenção do Sono/terapia , Estresse Psicológico/terapia , Resultado do TratamentoRESUMO
Autophagosome-tethering compounds (ATTECs) are an emerging new technology in targeted protein degradation. However, effective tools and successful examples for autophagosome-tethering chimeras are still rather limited. Herein, ATTEC ispinesib was identified for the first time to be an effective warhead to design autophagosome-tethering chimeras. As a conceptual validation study, the first generation of autophagic degraders of nicotinamide phosphoribosyltransferase (NAMPT) were developed by connecting the NAMPT inhibitor and LC3-binding ispinesib through a flexible linker. In particular, compound A3 significantly induced the degradation of NAMPT through the autophagy-lysosomal pathway, leading to excellent cellular antitumor potency. Ispinesib may have broad applications in the design of potent autophagosome-tethering chimeras.
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Autofagossomos , Nicotinamida Fosforribosiltransferase , Autofagossomos/metabolismo , Benzamidas , Quimera/metabolismo , Citocinas/metabolismo , Inibidores Enzimáticos/farmacologia , QuinazolinasRESUMO
The dose-related adverse effects of MDM2âP53 inhibitors have caused significant concern in the development of clinical safe anticancer agents. Herein we report an unprecedented homo-PROTAC strategy for more effective disruption of MDM2âP53 interaction. The design concept is inspired by the capacity of sub-stoichiometric catalytic PROTACs enabling to degrade an unwanted protein and the dual functions of MDM2 as an E3 ubiquitin ligase and a binding protein with tumor suppressor P53. The new homo-PROTACs are designed to induce self-degradation of MDM2. The results of the investigation have shown that PROTAC 11a efficiently dimerizes MDM2 with highly competitive binding activity and induces proteasome-dependent self-degradation of MDM2 in A549 non-small cell lung cancer cells. Furthermore, markedly, enantiomer 11a-1 exhibits potent in vivo antitumor activity in A549 xenograft nude mouse model, which is the first example of homo-PROTAC with in vivo therapeutic potency. This study demonstrates the potential of the homo-PROTAC as an alternative chemical tool for tumorigenic MDM2 knockdown, which could be developed into a safe therapy for cancer treatment.