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1.
Nat Immunol ; 23(6): 960-970, 2022 06.
Article in English | MEDLINE | ID: mdl-35654851

ABSTRACT

The emergence of current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) and potential future spillovers of SARS-like coronaviruses into humans pose a major threat to human health and the global economy. Development of broadly effective coronavirus vaccines that can mitigate these threats is needed. Here, we utilized a targeted donor selection strategy to isolate a large panel of human broadly neutralizing antibodies (bnAbs) to sarbecoviruses. Many of these bnAbs are remarkably effective in neutralizing a diversity of sarbecoviruses and against most SARS-CoV-2 VOCs, including the Omicron variant. Neutralization breadth is achieved by bnAb binding to epitopes on a relatively conserved face of the receptor-binding domain (RBD). Consistent with targeting of conserved sites, select RBD bnAbs exhibited protective efficacy against diverse SARS-like coronaviruses in a prophylaxis challenge model in vivo. These bnAbs provide new opportunities and choices for next-generation antibody prophylactic and therapeutic applications and provide a molecular basis for effective design of pan-sarbecovirus vaccines.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , Broadly Neutralizing Antibodies , COVID-19/prevention & control , Humans , Spike Glycoprotein, Coronavirus
2.
Immunity ; 56(3): 669-686.e7, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36889306

ABSTRACT

Pan-betacoronavirus neutralizing antibodies may hold the key to developing broadly protective vaccines against novel pandemic coronaviruses and to more effectively respond to SARS-CoV-2 variants. The emergence of Omicron and subvariants of SARS-CoV-2 illustrates the limitations of solely targeting the receptor-binding domain (RBD) of the spike (S) protein. Here, we isolated a large panel of broadly neutralizing antibodies (bnAbs) from SARS-CoV-2 recovered-vaccinated donors, which targets a conserved S2 region in the betacoronavirus spike fusion machinery. Select bnAbs showed broad in vivo protection against all three deadly betacoronaviruses, SARS-CoV-1, SARS-CoV-2, and MERS-CoV, which have spilled over into humans in the past two decades. Structural studies of these bnAbs delineated the molecular basis for their broad reactivity and revealed common antibody features targetable by broad vaccination strategies. These bnAbs provide new insights and opportunities for antibody-based interventions and for developing pan-betacoronavirus vaccines.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Broadly Neutralizing Antibodies , Antibodies, Neutralizing , Antibodies, Viral
3.
Proc Natl Acad Sci U S A ; 121(37): e2404965121, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39236234

ABSTRACT

Peroxymonosulfate-based electrochemical advanced oxidation processes (PMS-EAOPs) have great potential for sustainable water purification, so an in-depth understanding of its catalytic mechanism is imperative to facilitate its practical application. Herein, the performance enhancement and mechanism of electroenhanced PMS activation by single-atom Fe catalyst modified carbon felt was investigated. Compared with the anode, the cathode exhibited faster bisphenol A degradation (kcathode = 0.073 vs. kanode = 0.015 min-1), increased PMS consumption (98.8 vs. 10.3%), and an order of magnitude reduction of Fe dissolution (0.068 vs. 0.787 mg L-1). Mass transfer is a key factor limiting PMS activation, while the electrostriction of water in the hydrophobic region caused by cathode electric field (CEF) significantly increased mass transfer coefficient (km, cathode = 1.49 × 10-4 vs. km, anode = 2.68 × 10-5 m s-1). The enhanced activation of PMS is a synergistic result between electroactivation and catalyst-activation, which is controlled by the applied current density. 1O2 and direct electron transfer are the main active species and activation pathway, which achieve high degradation efficiency over pH 3 to 10. Density functional theory calculations prove CEF increases the adsorption energy, lengthens the O-O bond in PMS, and promotes charge transfer. A flow-through convection unit achieves sustainable operation with high removal efficiency (99.5% to 97.5%), low electrical energy consumption (0.15 kWh log-1 m-3), and low Fe leaching (0.81% of the total single atom Fe). This work reveals the critical role of electric fields in modulating Fenton-like catalytic activity, which may advance the development of advanced oxidation processes and other electrocatalytic applications.

4.
PLoS Pathog ; 20(9): e1012042, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39250525

ABSTRACT

The generation of broadly neutralizing antibodies (bnAbs) to conserved epitopes on HIV Envelope (Env) is one of the cornerstones of HIV vaccine research. The animal models commonly used for HIV do not reliably produce a potent broadly neutralizing serum antibody response, with the exception of cows. Cows have previously produced a CD4 binding site response by homologous prime and boosting with a native-like Env trimer. In small animal models, other engineered immunogens were shown to focus antibody responses to the bnAb V2-apex region of Env. Here, we immunized two groups of cows (n = 4) with two regimens of V2-apex focusing Env immunogens to investigate whether antibody responses could be generated to the V2-apex on Env. Group 1 was immunized with chimpanzee simian immunodeficiency virus (SIV)-Env trimer that shares its V2-apex with HIV, followed by immunization with C108, a V2-apex focusing immunogen, and finally boosted with a cross-clade native-like trimer cocktail. Group 2 was immunized with HIV C108 Env trimer followed by the same HIV trimer cocktail as Group 1. Longitudinal serum analysis showed that one cow in each group developed serum neutralizing antibody responses to the V2-apex. Eight and 11 bnAbs were isolated from Group 1 and Group 2 cows, respectively, and showed moderate breadth and potency. Potent and broad responses in this study developed much later than previous cow immunizations that elicited CD4bs bnAbs responses and required several different immunogens. All isolated bnAbs were derived from the ultralong CDRH3 repertoire. The finding that cow antibodies can target more than one broadly neutralizing epitope on the HIV surface reveals the generality of elongated structures for the recognition of highly glycosylated proteins. The exclusive isolation of ultralong CDRH3 bnAbs, despite only comprising a small percent of the cow repertoire, suggests these antibodies outcompete the long and short CDRH3 antibodies during the bnAb response.


Subject(s)
AIDS Vaccines , Antibodies, Neutralizing , HIV Antibodies , HIV-1 , env Gene Products, Human Immunodeficiency Virus , Animals , Cattle , HIV Antibodies/immunology , AIDS Vaccines/immunology , HIV-1/immunology , Antibodies, Neutralizing/immunology , env Gene Products, Human Immunodeficiency Virus/immunology , Epitopes/immunology , HIV Infections/immunology , HIV Infections/prevention & control , Female , Immunization , Humans , Broadly Neutralizing Antibodies/immunology , Simian Immunodeficiency Virus/immunology
5.
FASEB J ; 38(13): e23743, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38877852

ABSTRACT

Kisspeptin signaling regulates energy homeostasis. Adiposity is the principal source and receiver of peripheral Kisspeptin, and adipose Kiss1 metastasis suppressor (Kiss1) gene expression is stimulated by exercise. However, whether the adipose Kiss1 gene regulates energy homeostasis and plays a role in adaptive alterations during prolonged exercise remains unknown. Here, we investigated the role of Kiss1 role in mice and adipose tissues and the adaptive changes it induces after exercise, using adipose-specific Kiss1 knockout (Kiss1adipoq-/-) and adeno-associated virus-induced adipose tissue Kiss1-overexpressing (Kiss1adipoq over) mice. We found that adipose-derived kisspeptin signal regulates lipid and glucose homeostasis to maintain systemic energy homeostasis, but in a sex-dependent manner, with more pronounced metabolic changes in female mice. Kiss1 regulated adaptive alterations of genes and proteins in tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OxPhos) pathways in female gWAT following prolonged aerobic exercise. We could further show that adipose Kiss1 deficiency leads to reduced peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1α) protein content of soleus muscle and maximum oxygen uptake (VO2 max) of female mice after prolonged exercise. Therefore, adipose Kisspeptin may be a novel adipokine that increases organ sensitivity to glucose, lipids, and oxygen following exercise.


Subject(s)
Adipose Tissue , Energy Metabolism , Homeostasis , Kisspeptins , Mice, Knockout , Physical Conditioning, Animal , Animals , Kisspeptins/metabolism , Kisspeptins/genetics , Female , Mice , Physical Conditioning, Animal/physiology , Male , Adipose Tissue/metabolism , Mice, Inbred C57BL , Adaptation, Physiological
6.
Rev Med Virol ; 34(5): e2575, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39160646

ABSTRACT

Neurotropic viral infections pose a significant challenge due to their ability to target the central nervous system and cause severe neurological complications. Traditional antiviral therapies face limitations in effectively treating these infections, primarily due to the blood-brain barrier, which restricts the delivery of therapeutic agents to the central nervous system. Nanoparticle-based therapies have emerged as a promising approach to overcome these challenges. Nanoparticles offer unique properties that facilitate drug delivery across biological barriers, such as the blood-brain barrier, and can be engineered to possess antiviral activities.


Subject(s)
Antiviral Agents , Blood-Brain Barrier , Central Nervous System Viral Diseases , Nanoparticles , Humans , Nanoparticles/chemistry , Antiviral Agents/therapeutic use , Antiviral Agents/pharmacology , Animals , Blood-Brain Barrier/drug effects , Central Nervous System Viral Diseases/drug therapy , Central Nervous System Viral Diseases/virology , Drug Delivery Systems , Virus Diseases/drug therapy , Virus Diseases/virology
7.
Proc Natl Acad Sci U S A ; 119(29): e2205784119, 2022 07 19.
Article in English | MEDLINE | ID: mdl-35767670

ABSTRACT

Many neutralizing antibodies (nAbs) elicited to ancestral severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through natural infection and vaccination have reduced effectiveness to SARS-CoV-2 variants. Here, we show that therapeutic antibody ADG20 is able to neutralize SARS-CoV-2 variants of concern (VOCs) including Omicron (B.1.1.529) as well as other SARS-related coronaviruses. We delineate the structural basis of this relatively escape-resistant epitope that extends from one end of the receptor binding site (RBS) into the highly conserved CR3022 site. ADG20 can then benefit from high potency through direct competition with ACE2 in the more variable RBS and interaction with the more highly conserved CR3022 site. Importantly, antibodies that are able to target this site generally neutralize a broad range of VOCs, albeit with reduced potency against Omicron. Thus, this conserved and vulnerable site can be exploited for the design of universal vaccines and therapeutic antibodies.


Subject(s)
Antibodies, Monoclonal , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/virology , Epitopes/immunology , Humans , Neutralization Tests , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology
8.
Nano Lett ; 24(26): 7879-7885, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38901023

ABSTRACT

Twisted bilayer graphene (tBLG) possesses intriguing physical properties including unconventional superconductivity, enhanced light-matter interaction due to the formation of van Hove singularities (vHS), and a divergence of density of states in the electronic band structures. The vHS energy band gap provides optical resonant transition channels that can be tuned by the twist angle and interlayer coupling. Raman spectroscopy provides rich information on the vHS structure of tBLG. Here, we report the discovery of an ultralow-frequency Raman mode at ∼49 cm-1 in tBLG. This mode is assigned to the combination of ZA (an out-of-plane acoustic phonon) and TA (a transverse acoustic phonon) phonons, and the Raman scattering is proposed to occur at the so-called mini-valley. This mode is found to be particularly sensitive to the change in vHS in tBLG. Our findings may deepen the understanding of Raman scattering in tBLG and help to reveal vHS-related electron-phonon interactions in tBLG.

9.
Nano Lett ; 24(5): 1494-1501, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38264980

ABSTRACT

The rapid progress in nanopore sensing has sparked interest in protein sequencing. Despite recent notable advancements in amino acid recognition using nanopores, chemical modifications usually employed in this process still need further refinements. One of the challenges is to enhance the chemical specificity to avoid downstream misidentification of amino acids. By employing adamantane to label proteinogenic amino acids, we developed an approach to fingerprint individual amino acids using the wild-type α-hemolysin nanopore. The unique structure of adamantane-labeled amino acids (ALAAs) improved the spatial resolution, resulting in distinctive current signals. Various nanopore parameters were explored using a machine-learning algorithm and achieved a validation accuracy of 81.3% for distinguishing nine selected amino acids. Our results not only advance the effort in single-molecule protein characterization using nanopores but also offer a potential platform for studying intrinsic and variant structures of individual molecules.


Subject(s)
Hemolysin Proteins , Nanopores , Hemolysin Proteins/chemistry , Amino Acids/chemistry , Amino Acid Sequence , Algorithms
10.
Cardiovasc Diabetol ; 23(1): 188, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824550

ABSTRACT

BACKGROUNDS: Insulin resistance (IR) plays a vital role in the pathogenesis of the metabolic dysfunction-associated steatotic liver disease (MASLD). However, it remains unclear whether triglyceride-glucose (TyG) related parameters, which serve as useful biomarkers to assess IR, have prognostic effects on mortality outcomes of MASLD. METHODS: Participants in the National Health and Nutrition Examination Survey (NHANES) database from 1999 to 2018 years were included. TyG and its related parameters [TyG-waist circumference (TyG-WC) and TyG-waist to height ratio (TyG-WHtR)] were calculated. Kaplan-Meier curves, Cox regression analysis, and restricted cubic splines (RCS) were conducted to evaluate the association between TyG-related indices with the all-cause and cardiovascular mortality of adults with MASLD. The concordance index (C-index) was used to evaluate the prediction accuracy of TyG-related indices. RESULTS: A total of 8208 adults (4209 men and 3999 women, median age 49.00 years) with MASLD were included in this study. Multivariate-adjusted Cox regression analysis revealed that high quartile levels of TyG-related indices were significantly associated with the all-cause mortality of participants with MASLD [TyGadjusted hazard ratio (aHR) = 1.25, 95% confidence interval (CI) 1.05-1.50, P = 0.014; TyG-WCaHR for all-cause mortality = 1.28, 95% CI 1.07-1.52, P = 0.006; TyG-WHtRaHR for all-cause mortality = 1.50, 95% CI 1.25-1.80, P < 0.001; TyG-WCaHR for cardiovascular mortality = 1.81, 95% CI 1.28-2.55, P = 0.001; TyG-WHtRaHR for cardiovascular mortality = 2.22, 95% CI 1.55-3.17, P < 0.001]. The C-index of TyG-related indices for predicting all-cause mortality was 0.563 for the TyG index, 0.579 for the TyG-WC index, and 0.585 for the TyG-WHtR index, respectively. Regarding cardiovascular mortality, the C-index was 0.561 for the TyG index, 0.607 for the TyG-WC index, and 0.615 for the TyG-WHtR index, respectively. Nonlinear trends were observed between TyG and TyG-WC indices with all-cause mortality of MASLD (P < 0.001 and = 0.012, respectively). A non-linear relationship was observed between the TyG index and cardiovascular mortality of MASLD (P = 0.025). Subgroup analysis suggested that adults aged < 65 years old and those without comorbidities were more sensitive to the mortality prediction of TyG-related indices. CONCLUSION: Findings of this study highlight the predictive value of TyG-related indices, especially the TyG-WHtR index, in the mortality outcomes of adults with MASLD. TyG-related indices would be surrogate biomarkers for the clinical management of MASLD.


Subject(s)
Biomarkers , Blood Glucose , Cardiovascular Diseases , Cause of Death , Insulin Resistance , Nutrition Surveys , Triglycerides , Humans , Female , Male , Middle Aged , Triglycerides/blood , Prognosis , Risk Assessment , Biomarkers/blood , United States/epidemiology , Blood Glucose/metabolism , Cardiovascular Diseases/mortality , Cardiovascular Diseases/blood , Cardiovascular Diseases/diagnosis , Adult , Time Factors , Databases, Factual , Aged , Risk Factors , Non-alcoholic Fatty Liver Disease/mortality , Non-alcoholic Fatty Liver Disease/blood , Non-alcoholic Fatty Liver Disease/diagnosis , Cross-Sectional Studies , Predictive Value of Tests , Retrospective Studies
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