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1.
Emerg Microbes Infect ; 13(1): 2359004, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38779718

ABSTRACT

As SARS-CoV-2 continues to spread and mutate, tracking the viral evolutionary trajectory and understanding the functional consequences of its mutations remain crucial. Here, we characterized the antibody evasion, ACE2 receptor engagement, and viral infectivity of the highly mutated SARS-CoV-2 Omicron subvariant BA.2.87.1. Compared with other Omicron subvariants, including EG.5.1 and the current predominant JN.1, BA.2.87.1 exhibits less immune evasion, reduced viral receptor engagement, and comparable infectivity in Calu-3 lung cells. Intriguingly, two large deletions (Δ15-26 and Δ136-146) in the N-terminal domain (NTD) of the spike protein facilitate subtly increased antibody evasion but significantly diminish viral infectivity. Collectively, our data support the announcement by the USA CDC that the public health risk posed by BA.2.87.1 appears to be low.


Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , Immune Evasion , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Humans , SARS-CoV-2/immunology , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , COVID-19/virology , COVID-19/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antibodies, Viral/blood , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Cell Line , Mutation , Neutralization Tests
2.
Sex Med Rev ; 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38650382

ABSTRACT

INTRODUCTION: Peyronie's disease (PD) is a common penile disorder characterized by the formation of fibrous noncompliant hard nodules in the tunica albuginea of the penis. Collagenase Clostridium histolyticum (CCH) is an injectable drug that treats PD by enzymatically degrading plaque interstitial collagen. CCH has been used in patients with varying curvature, as well as in the acute and stable phases of the disease, through a variety of treatment regimens and combinations. We carried out a systematic review and meta-analysis to assess the efficacy of CCH combination therapies for PD. METHODS: We selected 4 observational comparative studies and 3 randomized controlled trials including 532 participants from the PubMed, Embase, and Cochrane databases (until December 2023) to evaluate the efficacy of CCH combination therapies for PD. The primary outcome was clinical efficacy as evaluated by improvement in penile curvature and penile length, as well as by scores on the Peyronie's Disease Questionnaire (PDQ) for symptom bother, penile pain, and psychological symptoms. Continuous data were represented by mean difference (MD) and 95% CI. All data were analyzed by Review Manager version 5.3. RESULTS: For penile length (MD, 0.81 cm; 95% CI, 0.17-1.45; P = .01), PDQ symptom bother (MD, -1.02; 95% CI, -1.83 to -0.21; P = .01), and PDQ penile pain (MD, -0.93; 95% CI, -1.50 to -0.36; P = .001), CCH combination therapy showed significantly greater improvements vs CCH monotherapy. However, in the other indicators, penile curvature and PDQ psychological symptoms, there was no significant difference between the therapies. CONCLUSION: This meta-analysis supports that CCH combination therapies can partially increase penile length and ameliorate symptom bother and penile pain to some extent. However, CCH combination therapies still need to be evaluated through more high-quality research.

3.
Food Chem ; 449: 139166, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38604025

ABSTRACT

Apostichopus japonicus (A. japonicus) has rich nutritional value and is an important economic crop. Due to its rich endogenous enzyme system, fresh A. japonicus is prone to autolysis during market circulation and storage, resulting in economic losses. In order to alleviate this phenomenon, we investigated the effect of polyphenol oxidase (PPO) mediated (-)-epigallocatechin gallate (EGCG) on the activity and structure of endogenous cathepsin series protein (CEP) from A. japonicus. Research on cathepsin activity showed that PPO mediated EGCG could significantly reduce enzyme activity, resulting in a decrease in enzymatic reaction rate. SDS-PAGE and scanning electron microscopy results showed that PPO mediates EGCG could induce CEP aggregation to form protein aggregates. Various spectral results indicated that EGCG caused changes in the structure of CEP. Meanwhile, the conjugates formed by PPO mediated EGCG had lower thermal stability. In conclusion, PPO mediated EGCG was an effective method to inhibit the endogenous enzyme activity.


Subject(s)
Catechin , Catechin/analogs & derivatives , Catechol Oxidase , Cathepsins , Stichopus , Catechin/chemistry , Catechin/pharmacology , Catechol Oxidase/metabolism , Catechol Oxidase/chemistry , Animals , Stichopus/enzymology , Stichopus/chemistry , Cathepsins/metabolism , Cathepsins/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Stability , Kinetics
4.
J Nanobiotechnology ; 22(1): 126, 2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38519957

ABSTRACT

The successful reprogramming of impaired wound healing presents ongoing challenges due to the impaired tissue microenvironment caused by severe bacterial infection, excessive oxidative stress, as well as the inappropriate dosage timing during different stages of the healing process. Herein, a dual-layer hydrogel with sodium alginate (SA)-loaded zinc oxide (ZnO) nanoparticles and poly(N-isopropylacrylamide) (PNIPAM)-loaded Cu5.4O ultrasmall nanozymes (named programmed time-released multifunctional hydrogel, PTMH) was designed to dynamically regulate the wound inflammatory microenvironment based on different phases of wound repairing. PTMH combated bacteria at the early phase of infection by generating reactive oxygen species through ZnO under visible-light irradiation with gradual degradation of the lower layer. Subsequently, when the upper layer was in direct contact with the wound tissue, Cu5.4O ultrasmall nanozymes were released to scavenge excessive reactive oxygen species. This neutralized a range of inflammatory factors and facilitated the transition from the inflammatory phase to the proliferative phase. Furthermore, the utilization of Cu5.4O ultrasmall nanozymes enhanced angiogenesis, thereby facilitating the delivery of oxygen and nutrients to the impaired tissue. Our experimental findings indicate that PTMHs promote the healing process of diabetic wounds with bacterial infection in mice, exhibiting notable antibacterial and anti-inflammatory properties over a specific period of time.


Subject(s)
Bacterial Infections , Zinc Oxide , Animals , Mice , Hydrogels/pharmacology , Reactive Oxygen Species , Zinc Oxide/pharmacology , Anti-Inflammatory Agents , Anti-Bacterial Agents/pharmacology
5.
Cell Host Microbe ; 32(3): 315-321.e3, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38377995

ABSTRACT

COVID-19 vaccines have recently been updated to specifically encode or contain the spike protein of the SARS-CoV-2 XBB.1.5 subvariant, but their immunogenicity in humans has yet to be fully evaluated and reported, particularly against emergent viruses that are rapidly expanding. We now report that administration of an updated monovalent mRNA vaccine booster (XBB.1.5 MV) to previously uninfected individuals boosted serum virus-neutralizing antibodies significantly against not only XBB.1.5 (27.0-fold increase) and EG.5.1 (27.6-fold increase) but also key emerging viruses such as HV.1, HK.3, JD.1.1, and JN.1 (13.3- to 27.4-fold increase). Individuals previously infected by an Omicron subvariant had the highest overall serum neutralizing titers (ID50 1,504-22,978) against all viral variants tested. While immunological imprinting was still evident with the updated vaccines, it was not nearly as severe as observed with the previously authorized bivalent BA.5 vaccine. Our findings strongly support the official recommendation to widely apply the updated COVID-19 vaccines.


Subject(s)
Antibodies, Neutralizing , mRNA Vaccines , Humans , COVID-19 Vaccines , Antibodies, Viral
6.
Adv Healthc Mater ; : e2304523, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38345186

ABSTRACT

Achieving hemostasis in penetrating and irregular wounds is challenging because the hemostasis factor cannot arrive at the bleeding site, and substantial bleeding will wash away the blood clot. Since the inherently gradual nature of blood clot formation takes time, a physical barrier is needed before blood clot formation. Herein, an ultra-light and shape memory hemostatic aerogel consisting of oxidized bacterial cellulose (OBC) and platelet extracellular vesicles (pVEs) is reported. The OBC-pVEs aerogel provides a physical barrier for the bleeding site by self-expansion, absorbing the liquid from blood to concentrate platelets and clotting factors and accelerating the clot formation by activating platelets and transforming fibrinogen into fibrin. In the rat liver and tail injury models, the blood loss decreases by 73% and 59%, and the bleeding times are reduced by 55% and 62%, respectively. OBC-pVEs aerogel has also been shown to accelerate wound healing. In conclusion, this work introduces an effective tool for treating deep, non-compressible, and irregular wounds and offers valuable strategies for trauma bleeding and wound treatment.

7.
Arthritis Rheumatol ; 76(4): 599-613, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37946666

ABSTRACT

OBJECTIVE: The peripheral B cell compartment is heavily disturbed in systemic lupus erythematosus (SLE), but whether B cells develop aberrantly in the bone marrow (BM) is largely unknown. METHODS: We performed single-cell RNA/B cell receptor (BCR) sequencing and immune profiling of BM B cells and classified patients with SLE into two groups: early B cell (Pro-B and Pre-B) normal (EBnor) and EB defective/low (EBlo) groups. RESULTS: The SLE-EBlo group exhibited more severe disease activity and proinflammatory status, overaction of type I interferon signaling and metabolic pathways within the B cell compartment, and aberrant BCR repertoires compared with the SLE-EBnor group. Moreover, in one patient with SLE who was initially classified in the SLE-EBlo group, early B cell deficiency and associated abnormalities were largely rectified in a second BM sample at the remission phase. CONCLUSION: In summary, this study suggests that early B cell loss in BM defines a unique pathological state in a subset of patients with SLE that may play an active role in the dysregulated autoimmune responses.


Subject(s)
Bone Marrow , Lupus Erythematosus, Systemic , Humans , Child , Bone Marrow/pathology , Developmental Disabilities/metabolism , Developmental Disabilities/pathology , B-Lymphocytes , Signal Transduction
8.
Food Chem ; 437(Pt 2): 137918, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-37925780

ABSTRACT

In this work, phlorotannin extracts (PhTEs) were isolated from Ascophyllum nodosum. The effects of PhTEs on the textural properties, structural changes and oxidation level of Apostichopus japonicus (A. japonicus) were investigated. The results showed that thermal treatment could lead to the dissolution of TCA-soluble peptides and free hydroxyproline and promote the degradation of A. japonicus. The chemical compositional changes and texture profile analysis results indicated that PhTEs could effectively inhibit the degradation of A. japonicus and improve the hardness and chewiness of A. japonicus. Analysis of multiple spectroscopic methods suggested that the secondary and tertiary conformations tended to be stable after PhTEs were added. In addition, electron spin resonance results indicated that PhTEs could reduce the oxidation level of A. japonicus. These results suggest that the degradation of A. japonicus during mild heat treatment can be regulated by PhTEs, which provides insights for quality control in A. japonicus heat treatment.


Subject(s)
Ascophyllum , Stichopus , Animals , Ascophyllum/chemistry , Oxidation-Reduction
9.
Cell Rep Med ; 4(11): 101258, 2023 11 21.
Article in English | MEDLINE | ID: mdl-37909042

ABSTRACT

To combat the evolving SARS-CoV-2 Omicron variants, bivalent COVID-19 mRNA vaccines, encoding both ancestral and Omicron BA.5 spikes, have replaced monovalent vaccines in numerous countries. However, fourth doses of either vaccine result in similar neutralizing antibody titers against Omicron subvariants, raising the possibility of immunological imprinting. To address this, we investigate antibody responses in 72 participants given three doses of a monovalent mRNA vaccine, followed by a bivalent or monovalent booster, or those with breakthrough infections with BA.5 or BQ. Bivalent boosters do not show notably higher binding or virus-neutralizing titers against various SARS-CoV-2 variants compared to monovalent ones. However, breakthrough infections lead to significantly better neutralization of Omicron subvariants. Multiple analyses, including antigenic mapping, suggest that the ancestral spike in bivalent vaccines is causing deep immunological imprinting, preventing broadening of antibodies to the BA.5 component, thereby defeating its intended goal. Its removal from future vaccine compositions is therefore strongly recommended.


Subject(s)
COVID-19 , Humans , Vaccines, Combined , COVID-19/prevention & control , COVID-19 Vaccines , SARS-CoV-2/genetics , Antibodies, Neutralizing , Breakthrough Infections
10.
iScience ; 26(11): 108254, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38026207

ABSTRACT

SARS-CoV-2 Omicron BA.2.75 has diversified into multiple subvariants with additional spike mutations and several are expanding in prevalence, particularly CH.1.1 and BN.1. Here, we investigated the viral receptor affinities and neutralization evasion properties of major BA.2.75 subvariants actively circulating in different regions worldwide. We found two distinct evolutionary pathways and three newly identified mutations that shaped the virological features of these subvariants. One phenotypic group exhibited a discernible decrease in viral receptor affinities, but a noteworthy increase in resistance to antibody neutralization, as exemplified by CH.1.1, which is apparently as resistant as XBB.1.5. In contrast, a second group demonstrated a substantial increase in viral receptor affinity but only a moderate increase in antibody evasion, as exemplified by BN.1. We also observed that all prevalent SARS-CoV-2 variants in the circulation presently, except for BN.1, exhibit profound levels of antibody evasion, suggesting this is the dominant determinant of virus transmissibility today.

11.
Nature ; 624(7992): 639-644, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37871613

ABSTRACT

A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariant, BA.2.86, has emerged and spread to numerous countries worldwide, raising alarm because its spike protein contains 34 additional mutations compared with its BA.2 predecessor1. We examined its antigenicity using human sera and monoclonal antibodies (mAbs). Reassuringly, BA.2.86 was no more resistant to human sera than the currently dominant XBB.1.5 and EG.5.1, indicating that the new subvariant would not have a growth advantage in this regard. Importantly, sera from people who had XBB breakthrough infection exhibited robust neutralizing activity against all viruses tested, suggesting that upcoming XBB.1.5 monovalent vaccines could confer added protection. Although BA.2.86 showed greater resistance to mAbs to subdomain 1 (SD1) and receptor-binding domain (RBD) class 2 and 3 epitopes, it was more sensitive to mAbs to class 1 and 4/1 epitopes in the 'inner face' of the RBD that is exposed only when this domain is in the 'up' position. We also identified six new spike mutations that mediate antibody resistance, including E554K that threatens SD1 mAbs in clinical development. The BA.2.86 spike also had a remarkably high receptor affinity. The ultimate trajectory of this new SARS-CoV-2 variant will soon be revealed by continuing surveillance, but its worldwide spread is worrisome.


Subject(s)
Epitopes, B-Lymphocyte , Receptors, Virus , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Humans , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/immunology , Epitopes, B-Lymphocyte/immunology , Immunogenicity, Vaccine , Mutation , Receptors, Virus/metabolism , SARS-CoV-2/classification , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Immune Sera/immunology
13.
Immunity ; 56(10): 2442-2455.e8, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37776849

ABSTRACT

SARS-CoV-2 continues to evolve, with many variants evading clinically authorized antibodies. To isolate monoclonal antibodies (mAbs) with broadly neutralizing capacities against the virus, we screened serum samples from convalescing COVID-19 patients. We isolated two mAbs, 12-16 and 12-19, which neutralized all SARS-CoV-2 variants tested, including the XBB subvariants, and prevented infection in hamsters challenged with Omicron BA.1 intranasally. Structurally, both antibodies targeted a conserved quaternary epitope located at the interface between the N-terminal domain and subdomain 1, uncovering a site of vulnerability on SARS-CoV-2 spike. These antibodies prevented viral receptor engagement by locking the receptor-binding domain (RBD) of spike in the down conformation, revealing a mechanism of virus neutralization for non-RBD antibodies. Deep mutational scanning showed that SARS-CoV-2 could mutate to escape 12-19, but such mutations are rarely found in circulating viruses. Antibodies 12-16 and 12-19 hold promise as prophylactic agents for immunocompromised persons who do not respond robustly to COVID-19 vaccines.


Subject(s)
COVID-19 , Spike Glycoprotein, Coronavirus , Animals , Cricetinae , Humans , COVID-19 Vaccines , SARS-CoV-2 , Receptors, Virus , Antibodies, Monoclonal , Antibodies, Viral , Antibodies, Neutralizing
14.
Drug Des Devel Ther ; 17: 2805-2819, 2023.
Article in English | MEDLINE | ID: mdl-37719360

ABSTRACT

Purpose: This study aims to confirm the efficacy of Xijiao Dihuang decoction (XJDHT), a classic prescription, in treating psoriasis and to explore the potential therapeutic mechanism. Methods: For pharmacodynamic analysis, a mouse model of imiquimod cream (IMQ)-induced psoriasis was constructed. Active ingredients and genes of XJDHT, as well as psoriasis-related targets, were obtained from public databases. Intersecting genes (IGEs) of XJDHT and psoriasis were collected by Venn Diagram. A protein-protein interaction (PPI) network of IGEs is constructed through the STRING database. The Molecular Complex Detection (MCODE) and Cytohubba plug-ins of Cytoscape software were used to identified hub genes. In addition, we conducted enrichment analysis of IGEs using the R package clusterProfiler. Hub genes were validated via external GEO databases. The influence of XJDHT on Hub gene expression was examined by qPCR and ELISA, and molecular docking was used to evaluate the binding efficacy between active ingredients and hub genes. Results: The results revealed that XJDHT possesses 92 potential genes for psoriasis, and 8 Hub genes were screened. Enrichment analysis suggested that XJDHT ameliorate psoriasis through multiple pathways, including AGE-RAGE, HIF-1, IL-17 and TNF signaling pathway. Validation data confirmed the differential expression of IL6, VEGFA, TNF, MMP9, STAT3, and TLR4. Molecular docking revealed a strong affinity between active ingredients and Hub genes. The efficacy of XJDHT in improving psoriatic lesions in model mice was demonstrated by PASI score and HE staining, potentially attributed to the down-regulation of VEGFA, MMP9, STAT3, TNF, and IL-17A, as evidenced by ELISA and qPCR. Conclusion: This study employed network pharmacology and in vitro experiments to identify the potential mechanisms underlying the therapeutic effects of XJDHT on psoriasis, providing a new theoretical basis for its clinical application in the treatment of psoriasis.


Subject(s)
Network Pharmacology , Psoriasis , Animals , Mice , Matrix Metalloproteinase 9 , Molecular Docking Simulation , Databases, Factual , Psoriasis/drug therapy
15.
Front Immunol ; 14: 1190416, 2023.
Article in English | MEDLINE | ID: mdl-37275896

ABSTRACT

Accurate identification of beneficial mutations is central to antibody design. Many knowledge-based (KB) computational approaches have been developed to predict beneficial mutations, but their accuracy leaves room for improvement. Thermodynamic integration (TI) is an alchemical free energy algorithm that offers an alternative technique for identifying beneficial mutations, but its performance has not been evaluated. In this study, we developed an efficient TI protocol with high accuracy for predicting binding free energy changes of antibody mutations. The improved TI method outperforms KB methods at identifying both beneficial and deleterious mutations. We observed that KB methods have higher accuracies in predicting deleterious mutations than beneficial mutations. A pipeline using KB methods to efficiently exclude deleterious mutations and TI to accurately identify beneficial mutations was developed for high-throughput mutation scanning. The pipeline was applied to optimize the binding affinity of a broadly sarbecovirus neutralizing antibody 10-40 against the circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant. Three identified beneficial mutations show strong synergy and improve both binding affinity and neutralization potency of antibody 10-40. Molecular dynamics simulation revealed that the three mutations improve the binding affinity of antibody 10-40 through the stabilization of an altered binding mode with increased polar and hydrophobic interactions. Above all, this study presents an accurate and efficient TI-based approach for optimizing antibodies and other biomolecules.


Subject(s)
COVID-19 , Humans , COVID-19/genetics , SARS-CoV-2/genetics , Antibodies , Thermodynamics , Mutation , Broadly Neutralizing Antibodies
16.
Emerg Microbes Infect ; 12(1): 2210237, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37132357

ABSTRACT

The SARS-CoV-2 Omicron subvariants have dominated the pandemic due to their high transmissibility and immune evasion conferred by the spike mutations. The Omicron subvariants can spread by cell-free virus infection and cell-cell fusion, the latter of which is more effective but has not been extensively investigated. In this study, we developed a simple and high-throughput assay that provides a rapid readout to quantify cell-cell fusion mediated by the SARS-CoV-2 spike proteins without using live or pseudotyped virus. This assay can be used to identify variants of concern and to screen for prophylactic and therapeutic agents. We further evaluated a panel of monoclonal antibodies (mAbs) and vaccinee sera against D614G and Omicron subvariants, finding that cell-cell fusion is substantially more resistant to mAb and serum inhibition than cell-free virus infection. Such results have important implications for the development of vaccines and antiviral antibody drugs against cell-cell fusion induced by SARS-CoV-2 spikes.


Subject(s)
Antibodies, Neutralizing , COVID-19 , Humans , Cell Fusion , SARS-CoV-2 , Antibodies, Viral , Antibodies, Monoclonal/pharmacology , Antiviral Agents , Spike Glycoprotein, Coronavirus/genetics
17.
Genes (Basel) ; 14(5)2023 04 30.
Article in English | MEDLINE | ID: mdl-37239391

ABSTRACT

Valine-glutamine (VQ) motif-containing proteins are transcriptional regulatory cofactors that play critical roles in plant growth and response to biotic and abiotic stresses. However, information on the VQ gene family in foxtail millet (Setaria italica L.) is currently limited. In this study, a total of 32 SiVQ genes were identified in foxtail millet and classified into seven groups (I-VII), based on the constructed phylogenetic relationships; the protein-conserved motif showed high similarity within each group. Gene structure analysis showed that most SiVQs had no introns. Whole-genome duplication analysis revealed that segmental duplications contributed to the expansion of the SiVQ gene family. The cis-element analysis demonstrated that growth and development, stress response, and hormone-response-related cis-elements were all widely distributed in the promoters of the SiVQs. Gene expression analysis demonstrated that the expression of most SiVQ genes was induced by abiotic stress and phytohormone treatments, and seven SiVQ genes showed significant upregulation under both abiotic stress and phytohormone treatments. A potential interaction network between SiVQs and SiWRKYs was predicted. This research provides a basis to further investigate the molecular function of VQs in plant growth and abiotic stress responses.


Subject(s)
Setaria Plant , Setaria Plant/genetics , Setaria Plant/metabolism , Plant Growth Regulators/genetics , Plant Growth Regulators/pharmacology , Plant Growth Regulators/metabolism , Plant Proteins/metabolism , Phylogeny , Gene Expression Regulation, Plant , Multigene Family , Stress, Physiological/genetics , Hormones
18.
J Virol ; 97(6): e0035623, 2023 06 29.
Article in English | MEDLINE | ID: mdl-37199648

ABSTRACT

Influenza C virus (ICV) is increasingly associated with community-acquired pneumonia (CAP) in children and its disease severity is worse than the influenza B virus, but similar to influenza A virus associated CAP. Despite the ubiquitous infection landscape of ICV in humans, little is known about its replication and pathobiology in animals. The goal of this study was to understand the replication kinetics, tissue tropism, and pathogenesis of human ICV (huICV) in comparison to the swine influenza D virus (swIDV) in guinea pigs. Intranasal inoculation of both viruses did not cause clinical signs, however, the infected animals shed virus in nasal washes. The huICV replicated in the nasal turbinates, soft palate, and trachea but not in the lungs while swIDV replicated in all four tissues. A comparative analysis of tropism and pathogenesis of these two related seven-segmented influenza viruses revealed that swIDV-infected animals exhibited broad tissue tropism with an increased rate of shedding on 3, 5, and 7 dpi and high viral loads in the lungs compared to huICV. Seroconversion occurred late in the huICV group at 14 dpi, while swIDV-infected animals seroconverted at 7 dpi. Guinea pigs infected with huICV exhibited mild to moderate inflammatory changes in the epithelium of the soft palate and trachea, along with mucosal damage and multifocal alveolitis in the lungs. In summary, the replication kinetics and pathobiological characteristics of ICV in guinea pigs agree with the clinical manifestation of ICV infection in humans, and hence guinea pigs could be used to study these distantly related influenza viruses. IMPORTANCE Similar to influenza A and B, ICV infections are seen associated with bacterial and viral co-infections which complicates the assessment of its real clinical significance. Further, the antivirals against influenza A and B viruses are ineffective against ICV which mandates the need to study the pathobiological aspects of this virus. Here we demonstrated that the respiratory tract of guinea pigs possesses specific viral receptors for ICV. We also compared the replication kinetics and pathogenesis of huICV and swIDV, as these viruses share 50% sequence identity. The tissue tropism and pathology associated with huICV in guinea pigs are analogous to the mild respiratory disease caused by ICV in humans, thereby demonstrating the suitability of guinea pigs to study ICV. Our comparative analysis revealed that huICV and swIDV replicated differentially in the guinea pigs suggesting that the type-specific genetic differences can result in the disparity of the viral shedding and tissue tropism.


Subject(s)
Disease Models, Animal , Gammainfluenzavirus , Guinea Pigs , Orthomyxoviridae Infections , Thogotovirus , Animals , Humans , Administration, Intranasal , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/virology , Receptors, Virus
20.
bioRxiv ; 2023 Apr 10.
Article in English | MEDLINE | ID: mdl-37090592

ABSTRACT

SARS-CoV-2 continues to evolve and evade most existing neutralizing antibodies, including all clinically authorized antibodies. We have isolated and characterized two human monoclonal antibodies, 12-16 and 12-19, which exhibited neutralizing activities against all SARS-CoV-2 variants tested, including BQ.1.1 and XBB.1.5. They also blocked infection in hamsters challenged with Omicron BA.1 intranasally. Structural analyses revealed both antibodies targeted a conserved quaternary epitope located at the interface between the N-terminal domain and subdomain 1, revealing a previously unrecognized site of vulnerability on SARS-CoV-2 spike. These antibodies prevent viral receptor engagement by locking the receptor-binding domain of spike in the down conformation, revealing a novel mechanism of virus neutralization for non-RBD antibodies. Deep mutational scanning showed that SARS-CoV-2 could mutate to escape 12-19, but the responsible mutations are rarely found in circulating viruses. Antibodies 12-16 and 12-19 hold promise as prophylactic agents for immunocompromised persons who do not respond robustly to COVID-19 vaccines.

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