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Since SARS-CoV-2 Omicron variant emerged, it is constantly evolving into multiple sub-variants, including BF.7, BQ.1, BQ.1.1, XBB, XBB.1.5 and the recently emerged BA.2.86 and JN.1. Receptor binding and immune evasion are recognized as two major drivers for evolution of the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein. However, the underlying mechanism of interplay between two factors remains incompletely understood. Herein, we determined the structures of human ACE2 complexed with BF.7, BQ.1, BQ.1.1, XBB and XBB.1.5 RBDs. Based on the ACE2/RBD structures of these sub-variants and a comparison with the known complex structures, we found that R346T substitution in the RBD enhanced ACE2 binding upon an interaction with the residue R493, but not Q493, via a mechanism involving long-range conformation changes. Furthermore, we found that R493Q and F486V exert a balanced impact, through which immune evasion capability was somewhat compromised to achieve an optimal receptor binding. We propose a "two-steps-forward and one-step-backward" model to describe such a compromise between receptor binding affinity and immune evasion during RBD evolution of Omicron sub-variants.
Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Angiotensin-Converting Enzyme 2 , Spike Glycoprotein, Coronavirus/genetics , AntibodiesABSTRACT
Genome transcription and replication of influenza A virus (FluA), catalyzed by viral RNA polymerase (FluAPol), are delicately controlled across the virus life cycle. A switch from transcription to replication occurring at later stage of an infection is critical for progeny virion production and viral non-structural protein NS2 has been implicated in regulating the switch. However, the underlying regulatory mechanisms and the structure of NS2 remained elusive for years. Here, we determine the cryo-EM structure of the FluAPol-NS2 complex at ~3.0 Å resolution. Surprisingly, three domain-swapped NS2 dimers arrange three symmetrical FluPol dimers into a highly ordered barrel-like hexamer. Further structural and functional analyses demonstrate that NS2 binding not only hampers the interaction between FluAPol and the Pol II CTD because of steric conflicts, but also impairs FluAPol transcriptase activity by stalling it in the replicase conformation. Moreover, this is the first visualization of the full-length NS2 structure. Our findings uncover key molecular mechanisms of the FluA transcription-replication switch and have implications for the development of antivirals.
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Graphene nanoribbons (GNRs), quasi one-dimensional (1D) narrow strips of graphene, have shown promise for high-performance nanoelectronics due to their exceptionally high carrier mobility and structurally tunable bandgaps. However, producing chirality-uniform GNRs on insulating substrates remains a big challenge. Here, we report the successful growth of bilayer GNRs with predominantly armchair chirality and ultranarrow widths (<5 nm) on insulating hexagonal boron nitride (h-BN) substrates using chemical vapor deposition (CVD). The growth of GNRs is catalyzed by transition metal nanoparticles, including Fe, Co, and Ni, through a unique tip-growth mechanism. Notably, GNRs catalyzed by Ni exhibit a high purity (97.3%) of armchair chirality. Electron transport measurements indicate that the ultrathin bilayer armchair GNRs exhibit quasi-metallic behavior. This quasi-metallicity is further supported by density functional theory (DFT) calculations, which reveal a significantly reduced bandgap in bilayer armchair GNRs. The chirality-specific GNRs reported here offer promising advancements for the application of graphene in nanoelectronics.
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AIM: To evaluate whether the ribosome-crosslinked collagen membrane (RCCM) is non-inferior to the natural collagen membrane (NCM) used in regeneration surgery in terms of clinical attachment level (CAL) gain at 6 months. METHODS: Eighty patients diagnosed as generalized periodontitis presenting with isolated infrabony defect (≥4 mm deep) were enrolled and randomized to receive regenerative surgery, either with NCM or RCCM, both combined with deproteinized bovine bone mineral (DBBM). CAL, pocket probing depth (PPD), and gingival recession (GR) were recorded at baseline, 3, and 6 months postoperatively. Periapical radiographs were taken at baseline, immediately, and 6 months after surgery. Early wound healing index (EHI) and patients' responses were recorded at 2 weeks postoperatively. RESULTS: At 6 months post-surgery, the mean CAL gain was 3.1 ± 1.5 mm in the NCM group and 2.9 ± 1.5 mm in the RCCM group, while the mean PPD was 4.3 ± 1.1 mm in the NCM group and 4.2 ± 1.0 mm in the RCCM group. Both groups demonstrated a statistically significant improvement from the baseline (p < .01). RCCM was non-inferior to NCM concerning the primary outcome (CAL gain at 6 months). The GR at 6 months postoperatively was 1.3 ± 1.2 and 1.2 ± 1.1 mm, which showed no difference compared with baseline. At 6 months follow-up, the radiographic linear bone fill (RLBF) was 6.5 ± 2.8 and 5.5 ± 2.6 mm (p > .05), while the bone fill percentage (BF%) was 102.3 ± 53.5% and 92.3 ± 40.1% (p > .05), in the NCM and RCCM groups, respectively. There was no significant difference in EHI and postoperative responses between two groups. CONCLUSION: RCCM + DBBM resulted in no-inferior clinical and radiographic outcomes to NCM + DBBM for the treatment of isolated infrabony defect in 6 months.
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OBJECTIVES: In order to evaluate the effect of methacrylated hyaluronic acid (HAMA) hydrogels containing the recombinant human amelogenin (rhAm) in vitro and in vivo. BACKGROUND: The ultimate goal in treating periodontal disease is to control inflammation and achieve regeneration of periodontal tissues. In recent years, methacrylated hyaluronic acid (HAMA) containing recombinant human amyloid protein (rhAm) has been widely used as a new type of biomaterial in tissue engineering and regenerative medicine. However, there is a lack of comprehensive research on the periodontal regeneration effects of this hydrogel. This experiment aims to explore the application of photoresponsive recombinant human amelogenin-loaded hyaluronic acid hydrogel for periodontal tissue regeneration and provide valuable insights into its potential use in this field. MATERIALS AND METHODS: The effects of rhAm-HAMA hydrogel on the proliferation of human periodontal ligament cells (hPDLCs) were assessed using the CCK-8 kit. The osteogenic differentiation of hPDLCs was evaluated through ALP staining and real-time PCR. Calvarial parietal defects were created in 4-week-old Sprague Dawley rats and implanted with deproteinized bovine bone matrix in different treatment groups. The animals were euthanized after 4 and 8 weeks of healing. The bone volume of the defect was observed by micro-CT and histological analysis. RESULTS: Stimulating hPDLCs with rhAm-HAMA hydrogel did not significantly affect their proliferation (p > .05). ALP staining and real-time PCR results demonstrated that the rhAm-HAMA group exhibited a significant upregulation of osteoclastic gene expression (p < .05). Micro-CT results revealed a significant increase in mineralized tissue volume fraction (MTV/TV%), trabecular bone number (Tb.N), and mineralized tissue density (MTD) of the bone defect area in the rhAm-HAMA group compared to the other groups (p < .05). The results of hematoxylin and eosin staining and Masson staining at 8 weeks post-surgery further supported the results of the micro-CT. CONCLUSIONS: The results of this study indicate that rhAm-HAMA hydrogel could effectively promote the osteogenic differentiation of hPDLCs and stabilize bone substitutes in the defects that enhance the bone regeneration in vivo.
Subject(s)
Amelogenin , Bone Regeneration , Cell Differentiation , Cell Proliferation , Hyaluronic Acid , Hydrogels , Periodontal Ligament , Rats, Sprague-Dawley , Hyaluronic Acid/pharmacology , Animals , Bone Regeneration/drug effects , Amelogenin/pharmacology , Amelogenin/therapeutic use , Humans , Periodontal Ligament/drug effects , Rats , Cell Proliferation/drug effects , Cell Differentiation/drug effects , Recombinant Proteins/pharmacology , Recombinant Proteins/therapeutic use , Osteogenesis/drug effects , Male , X-Ray Microtomography , Cells, Cultured , Methacrylates , Biocompatible Materials/pharmacologyABSTRACT
Objective: The effectiveness of manual acupuncture for treating bronchial asthma is still debatable and broad, and the effects of different acupuncture points, treatment durations, or illness trajectories have never been rigorously assessed. The objective of this revised systematic review and subgroup meta-analysis of randomized controlled trials (RCTs) is to ascertain the clinical efficacy of manual acupuncture on bronchial asthma and whether these effects varied depending on the acupuncture points, length of treatment, or course of the disease. Materials and methods: PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria were followed for creating a systematic review and meta-analysis. From the beginning through March 25, 2022, six electronic databases were checked. For the treatment of asthma, all RCTs contrasting acupuncture therapy along with conventional treatment against conventional treatment alone were chosen. The information was examined using Review Manager version 5.3 and Comprehensive Meta-Analysis version 3. Clinical efficacy (including the effective rate and the recurrence rate) was the primary outcome, and pulmonary function (including FEV1%, PEF) and The secondary results were T-lymphocyte immunity (containing CD3+, CD4+, and CD8+). Based on the acupuncture points, length of therapy, and nature of the condition, subgroup analyses were carried out. Results: There were a total of 21 RCTs that enrolled 2510 individuals. According to the meta-findings, analysis's manual acupuncture in addition to conventional treatment significantly increased the effective rate when compared to conventional treatment alone [OR = 5.14 95% CI 3.58-7.38, P < .00001], lung functions [FEV1% (MD = 6.18, 95% CI 2.40-9.96, P = .001) and PEF (MD = 0.45 95% CI 0.18-0.73, P = .001)], immune functions [CD3+ T lymphocytes (MD = 7.55 95% CI 6.55-8.56, P < .00001), CD4+ T-lymphocytes (MD = 5.11 95% CI 4.09-6.13, P < .00001), T-lymphocyte CD8+ (MD = -0.37.11 95% CI -3.62--2.51, P < .00001)] and noteworthy reduction in the recurrence rate (OR = 0.19 95% CI 0.10-0.38, P < .00001). Results from the subgroup analysis were consistent. Conclusion: Manual acupuncture combined with Western Medicine is more effective than conventional treatment alone for bronchial asthma. Combination therapy can significantly improve clinical efficacy, lung function, and immune function while reducing the relapse rate. But to further support the results of this investigation, high-quality RCTs with long-term outcomes are still required, taking into account the inherent limitations of the included studies. Registration number: PROSPERO (no. CRD42022357805) (https://www.crd.york.ac.uk/prospero/).
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Poor systemic administration capability, a natural tendency to target CAR-positive cells, nonspecific shedding to normal organs, and poor viral persistence in tumor tissues are major hindrances to the therapeutic benefit of adenovirus (Ad) gene vectors in the clinical setting. Antheraea pernyi silk fibroin (ASF) grafted with targeted peptides was used to coat ING4-IL-24 dual-gene coexpressing adenovirus for targeted gene therapy of lung carcinoma. The dual-gene vector with a diameter of 390 nm could target and infect H460 lung tumor cells, internalize into cells, express the ING4 and IL-24 genes at a high level, effectively inhibit the proliferation of lung tumor cells, and induce their apoptosis. The in vivo treatment of H460 human lung carcinoma xenograft tumors showed that the dual-gene coexpressing vector suppressed the proliferation of lung tumor cells by downregulating the expression of Ki67 and Bcl-2, promoted apoptosis by upregulating the expression of C Caspase-3 and Bax, and blocked tumor angiogenesis by downregulating the expression of VEGF and CD31, thus exerting a multichannel tumor inhibition effect. Surface modification of Ad with targeted cationic silk fibroin is an effective way to solve the natural tendencies and in vivo instability of adenovirus vectors, and such vectors have potential for clinical application.
Subject(s)
Carcinoma , Fibroins , Lung Neoplasms , Moths , Animals , Humans , Fibroins/genetics , Lung , Lung Neoplasms/genetics , Lung Neoplasms/therapy , SilkABSTRACT
Nociceptive sensory neurons convey pain-related signals to the CNS using action potentials. Loss-of-function mutations in the voltage-gated sodium channel NaV1.7 cause insensitivity to pain (presumably by reducing nociceptor excitability) but clinical trials seeking to treat pain by inhibiting NaV1.7 pharmacologically have struggled. This may reflect the variable contribution of NaV1.7 to nociceptor excitability. Contrary to claims that NaV1.7 is necessary for nociceptors to initiate action potentials, we show that nociceptors can achieve similar excitability using different combinations of NaV1.3, NaV1.7, and NaV1.8. Selectively blocking one of those NaV subtypes reduces nociceptor excitability only if the other subtypes are weakly expressed. For example, excitability relies on NaV1.8 in acutely dissociated nociceptors but responsibility shifts to NaV1.7 and NaV1.3 by the fourth day in culture. A similar shift in NaV dependence occurs in vivo after inflammation, impacting ability of the NaV1.7-selective inhibitor PF-05089771 to reduce pain in behavioral tests. Flexible use of different NaV subtypes exemplifies degeneracy - achieving similar function using different components - and compromises reliable modulation of nociceptor excitability by subtype-selective inhibitors. Identifying the dominant NaV subtype to predict drug efficacy is not trivial. Degeneracy at the cellular level must be considered when choosing drug targets at the molecular level.
Subject(s)
Analgesics , Benzenesulfonamides , Nociceptors , Phenyl Ethers , Animals , Analgesics/pharmacology , Nociceptors/metabolism , Nociceptors/drug effects , NAV1.7 Voltage-Gated Sodium Channel/metabolism , NAV1.7 Voltage-Gated Sodium Channel/genetics , Mice , Action Potentials/drug effects , Pain/drug therapy , Humans , Sodium Channels/metabolism , Sodium Channels/genetics , NAV1.8 Voltage-Gated Sodium Channel/metabolism , NAV1.8 Voltage-Gated Sodium Channel/geneticsABSTRACT
Cardiovascular diseases (CVDs) persist as the predominant cause of mortality, urging the exploration of innovative pharmaceuticals. Mitochondrial dysfunction stands as a pivotal contributor to CVDs development. Sirtuin 3 (SIRT3), a prominent mitochondrial deacetylase known for its crucial role in protecting mitochondria against damage and dysfunction, has emerged as a promising therapeutic target for CVDs treatment. Utilizing isosteviol, a natural ent-beyerene diterpenoid, 24 derivatives were synthesized and evaluated in vivo using a zebrafish model, establishing a deduced structure-activity relationship. Among these, derivative 5v exhibited significant efficacy in doxorubicin-induced cardiomyopathy in zebrafish and murine models. Subsequent investigations revealed that 5v selectively elevated SIRT3 expression, leading to the upregulation of SOD2 and OPA1 expression, effectively preventing mitochondrial dysfunction, mitigating oxidative stress, and preserving cardiomyocyte viability. As a novel structural class of SIRT3 activators with robust therapeutic effects, 5v emerges as a promising candidate for further drug development.
Subject(s)
Cardiotonic Agents , Diterpenes, Kaurane , Drug Design , Sirtuin 3 , Zebrafish , Animals , Sirtuin 3/metabolism , Sirtuin 3/antagonists & inhibitors , Diterpenes, Kaurane/pharmacology , Diterpenes, Kaurane/chemical synthesis , Diterpenes, Kaurane/chemistry , Diterpenes, Kaurane/therapeutic use , Cardiotonic Agents/pharmacology , Cardiotonic Agents/chemical synthesis , Cardiotonic Agents/chemistry , Cardiotonic Agents/therapeutic use , Structure-Activity Relationship , Mice , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Humans , Oxidative Stress/drug effects , Doxorubicin/pharmacologyABSTRACT
Introduction: ß-glucosidase is one class of pivotal glycosylhydrolase enzyme that can cleavage glucosidic bonds and transfer glycosyl group between the oxygen nucleophiles. Lactobacillus is the most abundant bacteria in the human gut. Identification and characterization of new ß-glucosidases from Lactobacillus are meaningful for food or drug industry. Method: Herein, an acid-adapted ß-glucosidase (LpBgla) was cloned and characterized from Lactobacillus paracasei. And the insight acid-adapted mechanism of LpBgla was investigated using molecular dynamics simulations. Results and Discussion: The recombinant LpBgla exhibited maximal activity at temperature of 30°C and pH 5.5, and the enzymatic activity was inhibited by Cu2+, Mn2+, Zn2+, Fe2+, Fe3+ and EDTA. The LpBgla showed a more stable structure, wider substrate-binding pocket and channel aisle, more hydrogen bonds and stronger molecular interaction with the substrate at pH 5.5 than pH 7.5. Five residues including Asp45, Leu60, Arg120, Lys153 and Arg164 might play a critical role in the acid-adapted mechanism of LpBgla. Moreover, LpBgla showed a broad substrate specificity and potential application in the bioconversion of glycosides, especially towards the arbutin. Our study greatly benefits for the development novel ß-glucosidases from Lactobacillus, and for the biosynthesis of aglycones.
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There are two main types of carbon nanotubes (CNTs): metallic and semiconducting. Naturally grown CNTs are randomly distributed, posing challenges in distinguishing between the two types. Here, a novel approach for nanoscale high-resolution imaging and identification of CNTs was introduced by incorporating the heterodyne technique into high-harmonic electrostatic force microscopy (HH-EFM) on an atomic force microscopy (AFM) platform. In the developed heterodyne HH-EFM, a more localized high-order gradient of tip-sample nonlinear interaction force is used as signal channels, resulting in an improved spatial resolution, compared to the conventional HH-EFM. Furthermore, the heterodyne HH-EFM also has the capability to visualize material carrier density and assess qualitative carrier transport performance. Our work not only presents a new approach to identifying/exploring electrical properties of low-dimensional nanomaterials but also provides a solution for optimizing resolution in long-range interaction-based functional AFM technologies.
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Background: Although there is solid epidemiological evidence supporting the connection between hypertension and gout, little has been said about the relationship between diastolic and systolic blood pressure and gout, the causal relationship and direction associated are uncertain, so we aim to research the causal relationship between diastolic and systolic blood pressure and gout. Methods: We conducted a two-sample Mendelian randomization (MR) analysis to assess the causal effect between 2 blood pressure phenotypes (including diastolic blood pressure and systolic blood pressure) and 5 gout phenotypes (including gout, drug-induced gout, idiopathic gout, unspecified gout, and strictly defined gout) using genome-wide association study statistics. The inverse variance weighting method was used to generate the main results, while sensitivity analyses using MR-Egger, weighted median, Cochran's Q test, Egger intercept test, and leave-one-out analysis, were performed to assess the stability and reliability of the results. Results: After the screening, we found a causal relationship between diastolic blood pressure and gout, idiopathic gout, unspecified gout, and strictly defined gout, and a causal relationship between systolic blood pressure and gout, idiopathic gout, unspecified gout, and strictly defined gout. Conclusion: From a genetic predisposition, controlling blood pressure may reduce the risk of gout.
Subject(s)
Blood Pressure , Genome-Wide Association Study , Gout , Hypertension , Mendelian Randomization Analysis , Humans , Gout/genetics , Gout/epidemiology , Blood Pressure/genetics , Hypertension/genetics , Hypertension/epidemiology , Genetic Predisposition to Disease , Diastole , Systole , Polymorphism, Single Nucleotide , Risk FactorsABSTRACT
Anxiety- and depression-like behaviors are commonly observed clinical features of depression and many other mental disorders. Recent evidence has revealed the crucial role of the microbiota-gut-brain axis in the bidirectional communication between the gastrointestinal tract and the central nervous system. Supplementation with psychobiotics may provide a novel approach for the adjunctive treatment of mental disorders by regulating the intestinal microecology. We isolated and identified a novel probiotic, Lactiplantibacillus plantarum D-9 (D-9), from traditional Chinese fermented foods in our previous work, which exhibited a high yield of gamma-aminobutyric acid (GABA). Herein, it was proved that the oral administration of D-9 could alleviate the depression- and anxiety-like behaviors of Chronic Unpredicted Mild Stress (CUMS) mice, and show non-toxicity or side-effects in the mice. Physiological and biochemical analyses demonstrated that D-9 regulated tryptophan metabolism, the HPA-axis and inflammation in CUMS mice. Moreover, D-9 modulated the structure and composition of the gut microbiota, leading to an increase in the relative abundance of Ligilactobacillus murinus and Lactobacillus johnsonii, and a decrease in the levels of Kineothrix alysoides and Helicobacter bilis compared to those in CUMS mice. Our work demonstrates that D-9 alleviated anxiety- and depression-like disorders in CUMS mice by modulating tryptophan metabolism and the gut microbiota. These findings provide an innovative strategy for the intervention and treatment of depressive disorders.
Subject(s)
Gastrointestinal Microbiome , Neuroprotective Agents , Humans , Animals , Mice , Tryptophan , Depression/drug therapy , Anxiety/drug therapyABSTRACT
Peri-implant lesion is a grave condition afflicting numerous indi-viduals with dental implants. It results from persistent periodontal bacteria accumulation causing inflammation around the implant site, which can primarily lead to implant loosening and ultimately the implant loss. Early-stage peri-implant lesions exhibit symptoms akin to gum disease, including swelling, redness and bleeding of the gums surrounding the implant. These signs indicate infection and inflammation of the peri-implant tissues, which may result in bone loss and implant failure. To address this problem, a thermionic strategy was applied by designing a cuprorivaite-hardystonite bioceramic/alginate composite hydrogel with photothermal and Cu/Zn/Si multiple ions releasing property. This innovative approach creates a thermionic effect by the release of bioactive ions (Cu2+ and Zn2+ and SiO32-) from the composite hydrogel and the mild heat environment though the photothermal effect of the composite hydrogel induced by near-infrared light irradiation. The most distinctive advantage of this thermionic effect is to substantially eliminate periodontal pathogenic bacteria and inhibit inflammation, while simultaneously enhance peri-implant osseointegration. This unique attribute renders the use of this composite hydrogel highly effective in significantly improving the survival rate of implants after intervention in peri-implant lesions, which is a clinical challenge in periodontics. This study reveals application potential of a new biomaterial-based approach for peri-implant lesion, as it not only eliminates the infection and inflammation, but also enhances the osteointegration of the dental implant, which provides theoretical insights and practical guidance to prevent and manage early-stage peri-implant lesion using bioactive functional materials.
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The development of solid-state electrolytes (SSEs) with outstanding comprehensive performance is currently a critical challenge for achieving high energy density and safer solid-state batteries (SSBs). In this study, a strategy of nano-confined in situ solidification is proposed to create a novel category of molten guest-mediated metal-organic frameworks, named MGM-MOFs. By embedding the newly developed molten crystalline organic electrolyte (ML20) into the nanocages of anionic MOF-OH, MGM-MOF-OH, characterized by multi-modal supramolecular interaction sites and continuous negative electrostatic environments within nano-channels, is achieved. These nanochannels promote ion transport through the successive hopping of Li+ between neighbored negative electrostatic environments and suppress anion movement through the chemical constraint of the hydroxyl-functionalized pore wall. This results in remarkable Li+ conductivity of 7.1 × 10-4 S cm-1 and high Li+ transference number of 0.81. Leveraging these advantages, the SSBs assembled with MGM-MOF-OH exhibit impressive cycle stability and a high specific energy density of 410.5 Wh kganode + cathode + electrolyte -1 under constrained conditions and various working temperatures. Unlike flammable traditional MOFs, MGM-MOF-OH demonstrates high robustness under various harsh conditions, including ignition, high voltage, and extended to humidity.
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Nanoparticle vaccines displaying mosaic receptor-binding domains (RBDs) or spike (S) from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or other sarbecoviruses are used in preparedness against potential zoonotic outbreaks. Here, we describe a self-assembling nanoparticle using lumazine synthase (LuS) as the scaffold to display RBDs from different sarbecoviruses. Mosaic nanoparticles induce sarbecovirus cross-neutralizing antibodies comparable to a nanoparticle cocktail. We find mosaic nanoparticles elicit a B cell receptor repertoire using an immunodominant germline gene pair of IGHV14-3:IGKV14-111. Most of the tested IGHV14-3:IGKV14-111 monoclonal antibodies (mAbs) are broadly cross-reactive to clade 1a, 1b, and 3 sarbecoviruses. Using mAb competition and cryo-electron microscopy, we determine that a representative IGHV14-3:IGKV14-111 mAb, M2-7, binds to a conserved epitope on the RBD, largely overlapping with the pan-sarbecovirus mAb S2H97. This suggests mosaic nanoparticles expand B cell recognition of the common epitopes shared by different clades of sarbecoviruses. These results provide immunological insights into the cross-reactive responses elicited by mosaic nanoparticles against sarbecoviruses.
Subject(s)
Nanoparticles , Nanoparticles/chemistry , Animals , Humans , SARS-CoV-2/immunology , Antibodies, Viral/immunology , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Mice , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/chemistry , Cross Reactions/immunology , Antibody Formation/immunology , COVID-19/immunology , COVID-19/virology , Protein Domains , Mice, Inbred BALB C , Multienzyme Complexes/immunology , Female , Immunodominant Epitopes/immunologyABSTRACT
Anticancer activity has been extensively studies. In this article, three ligands 2-(6-bromobenzo[d][1,3]dioxol-5-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (BDIP), 2-(7-methoxybenzo[d][1,3]dioxol-5-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (MDIP), 2-(6-nitrobenzo[d][1,3]dioxol-5-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (NDIP) and their iridium(III) complexes: [Ir(ppy)2(BDIP)](PF6) (ppy = deprotonated 2-phenylpyridine, 3a), [Ir(ppy)2(MDIP)](PF6) (3b) and [Ir(ppy)2(NDIP)](PF6) (3c) were synthesized. The cytotoxicity of 3a, 3b, 3c against Huh7, A549, BEL-7402, HepG2, HeLa, and non-cancer NIH3T3 was tested using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. The results obtained from the MTT test stated clearly that these complexes demonstrated moderate or non-cytotoxicity toward Huh7, BEL-7402, HepG2 and HeLa except A549 cells. To improve the anticancer efficacy, we used white light to irradiate the mixture of cells and complexes for 30 min, the anticancer activity of the complexes was greatly enhanced. Particularly, 3a and 3b exhibited heightened capability to inhibit A549 cells proliferation with IC50 (half maximal inhibitory concentration) values of 0.7 ± 0.3 µM and 1.8 ± 0.1 µM, respectively. Cellular uptake has shown that 3a and 3b can be accumulated in the cytoplasm. Wound healing and colony forming showed that 3a and 3b significantly hinder the cell migration and growth in the S phase. The complexes open mitochondrial permeability transition pore (MPTP) channel and cause the decrease of membrane potential, release of cytochrome C, activation of caspase 3, and finally lead to apoptosis. In addition, 3a and 3b cause autophagy, increase the lipid peroxidation and lead to ferroptosis. Also, 3a and 3b increase the expression of calreticulin (CRT), high mobility group box 1 (HMGB1), heat shock protein 70 (HSP70), thereby inducing immunogenic cell death.
Subject(s)
Antineoplastic Agents , Coordination Complexes , Iridium , Lung Neoplasms , Iridium/chemistry , Iridium/pharmacology , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Coordination Complexes/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/chemical synthesis , A549 Cells , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , Apoptosis/drug effects , Light , Animals , Mice , Cell Proliferation/drug effects , NIH 3T3 CellsABSTRACT
Van der Waals (vdW) assembly of low-dimensional materials has proven the capability of creating structures with on-demand properties. It is predicted that the vdW encapsulation can induce a local high-pressure of a few GPa, which will strongly modify the structure and property of trapped materials. Here, we report on the structural collapse of carbon nanotubes (CNTs) induced by the vdW encapsulation. By simply covering CNTs with a hexagonal boron nitride flake, most of the CNTs (≈77%) convert from a tubular structure to a collapsed flat structure. Regardless of their original diameters, all the collapsed CNTs exhibit a uniform height of ≈0.7 nm, which is roughly the thickness of bilayer graphene. Such structural collapse is further confirmed by Raman spectroscopy, which shows a prominent broadening and blue shift in the Raman G-peak. The vdW encapsulation-induced collapse of CNTs is fully captured by molecular dynamics simulations of the local vdW pressure. Further near-field optical characterization reveals a metal-semiconductor transition in accompany with the CNT structural collapse. Our study provides not only a convenient approach to generate local high-pressure for fundamental research, but also a collapsed-CNT semiconductor for nanoelectronic applications.
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The game between therapeutic monoclonal antibodies (mAbs) and continuously emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has favored the virus, as most therapeutic mAbs have been evaded. Addressing this challenge, we systematically explored a reproducible bispecific antibody (bsAb)-dependent synergistic effect in this study. It could effectively restore the neutralizing activity of the bsAb when any of its single mAbs is escaped by variants. This synergy is primarily attributed to the binding angle of receptor-binding domain (RBD)-5, facilitating inter-spike cross-linking and promoting cryptic epitope exposure that classical antibody cocktails cannot achieve. Furthermore, RBD-5 with RBD-2, RBD-6, and RBD-7, alongside RBD-8, also exhibit significantly enhanced effects. This study not only shifts the paradigm in understanding antibody interactions but paves the way for developing more effective therapeutic antibodies against rapidly mutating SARS-CoV-2, with Dia-19 already showing promise against emerging variants like BA.2.86, EG.5.1, and JN.1.