RESUMO
The BQ and XBB subvariants of SARS-CoV-2 Omicron are now rapidly expanding, possibly due to altered antibody evasion properties deriving from their additional spike mutations. Here, we report that neutralization of BQ.1, BQ.1.1, XBB, and XBB.1 by sera from vaccinees and infected persons was markedly impaired, including sera from individuals boosted with a WA1/BA.5 bivalent mRNA vaccine. Titers against BQ and XBB subvariants were lower by 13- to 81-fold and 66- to 155-fold, respectively, far beyond what had been observed to date. Monoclonal antibodies capable of neutralizing the original Omicron variant were largely inactive against these new subvariants, and the responsible individual spike mutations were identified. These subvariants were found to have similar ACE2-binding affinities as their predecessors. Together, our findings indicate that BQ and XBB subvariants present serious threats to current COVID-19 vaccines, render inactive all authorized antibodies, and may have gained dominance in the population because of their advantage in evading antibodies.
Assuntos
Anticorpos Antivirais , COVID-19 , Evasão da Resposta Imune , SARS-CoV-2 , Humanos , Anticorpos Monoclonais , Anticorpos Neutralizantes , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19 , SARS-CoV-2/classificação , SARS-CoV-2/genéticaRESUMO
The low-density lipoprotein (LDL) receptor-related protein 2 (LRP2 or megalin) is representative of the phylogenetically conserved subfamily of giant LDL receptor-related proteins, which function in endocytosis and are implicated in diseases of the kidney and brain. Here, we report high-resolution cryoelectron microscopy structures of LRP2 isolated from mouse kidney, at extracellular and endosomal pH. The structures reveal LRP2 to be a molecular machine that adopts a conformation for ligand binding at the cell surface and for ligand shedding in the endosome. LRP2 forms a homodimer, the conformational transformation of which is governed by pH-sensitive sites at both homodimer and intra-protomer interfaces. A subset of LRP2 deleterious missense variants in humans appears to impair homodimer assembly. These observations lay the foundation for further understanding the function and mechanism of LDL receptors and implicate homodimerization as a conserved feature of the LRP receptor subfamily.
Assuntos
Endocitose , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Animais , Humanos , Camundongos , Microscopia Crioeletrônica , Rim/metabolismo , Ligantes , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismoRESUMO
The vaccine-mediated elicitation of antibodies (Abs) capable of neutralizing diverse HIV-1 strains has been a long-standing goal. To understand how broadly neutralizing antibodies (bNAbs) can be elicited, we identified, characterized, and tracked five neutralizing Ab lineages targeting the HIV-1-fusion peptide (FP) in vaccinated macaques over time. Genetic and structural analyses revealed two of these lineages to belong to a reproducible class capable of neutralizing up to 59% of 208 diverse viral strains. B cell analysis indicated each of the five lineages to have been initiated and expanded by FP-carrier priming, with envelope (Env)-trimer boosts inducing cross-reactive neutralization. These Abs had binding-energy hotspots focused on FP, whereas several FP-directed Abs induced by immunization with Env trimer-only were less FP-focused and less broadly neutralizing. Priming with a conserved subregion, such as FP, can thus induce Abs with binding-energy hotspots coincident with the target subregion and capable of broad neutralization.
Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/classificação , Linfócitos B/citologia , Linfócitos B/metabolismo , Cristalografia por Raios X , Feminino , Células HEK293 , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/classificação , HIV-1/metabolismo , Humanos , Macaca mulatta , Masculino , Peptídeos/química , Estrutura Terciária de Proteína , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismoRESUMO
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.
Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Cricetinae , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , Receptores Virais , Anticorpos Monoclonais , Anticorpos Antivirais , Anticorpos NeutralizantesRESUMO
Nirmatrelvir, an oral antiviral targeting the 3CL protease of SARS-CoV-2, has been demonstrated to be clinically useful against COVID-19 (refs. 1,2). However, because SARS-CoV-2 has evolved to become resistant to other therapeutic modalities3-9, there is a concern that the same could occur for nirmatrelvir. Here we examined this possibility by in vitro passaging of SARS-CoV-2 in nirmatrelvir using two independent approaches, including one on a large scale. Indeed, highly resistant viruses emerged from both and their sequences showed a multitude of 3CL protease mutations. In the experiment peformed with many replicates, 53 independent viral lineages were selected with mutations observed at 23 different residues of the enzyme. Nevertheless, several common mutational pathways to nirmatrelvir resistance were preferred, with a majority of the viruses descending from T21I, P252L or T304I as precursor mutations. Construction and analysis of 13 recombinant SARS-CoV-2 clones showed that these mutations mediated only low-level resistance, whereas greater resistance required accumulation of additional mutations. E166V mutation conferred the strongest resistance (around 100-fold), but this mutation resulted in a loss of viral replicative fitness that was restored by compensatory changes such as L50F and T21I. Our findings indicate that SARS-CoV-2 resistance to nirmatrelvir does readily arise via multiple pathways in vitro, and the specific mutations observed herein form a strong foundation from which to study the mechanism of resistance in detail and to inform the design of next-generation protease inhibitors.
Assuntos
Antivirais , COVID-19 , Farmacorresistência Viral , SARS-CoV-2 , Humanos , Antivirais/farmacologia , COVID-19/virologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Farmacorresistência Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Mutação , Tratamento Farmacológico da COVID-19RESUMO
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.
Assuntos
Epitopos de Linfócito B , Receptores Virais , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Epitopos de Linfócito B/imunologia , Imunogenicidade da Vacina , Mutação , Receptores Virais/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Soros Imunes/imunologiaRESUMO
The B.1.1.529/Omicron variant of SARS-CoV-2 was only recently detected in southern Africa, but its subsequent spread has been extensive, both regionally and globally1. It is expected to become dominant in the coming weeks2, probably due to enhanced transmissibility. A striking feature of this variant is the large number of spike mutations3 that pose a threat to the efficacy of current COVID-19 vaccines and antibody therapies4. This concern is amplified by the findings of our study. Here we found that B.1.1.529 is markedly resistant to neutralization by serum not only from patients who recovered from COVID-19, but also from individuals who were vaccinated with one of the four widely used COVID-19 vaccines. Even serum from individuals who were vaccinated and received a booster dose of mRNA-based vaccines exhibited substantially diminished neutralizing activity against B.1.1.529. By evaluating a panel of monoclonal antibodies against all known epitope clusters on the spike protein, we noted that the activity of 17 out of the 19 antibodies tested were either abolished or impaired, including ones that are currently authorized or approved for use in patients. Moreover, we also identified four new spike mutations (S371L, N440K, G446S and Q493R) that confer greater antibody resistance on B.1.1.529. The Omicron variant presents a serious threat to many existing COVID-19 vaccines and therapies, compelling the development of new interventions that anticipate the evolutionary trajectory of SARS-CoV-2.
Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/virologia , Evasão da Resposta Imune/imunologia , SARS-CoV-2/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/sangue , COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Linhagem Celular , Convalescença , Evolução Molecular , Humanos , Soros Imunes/imunologia , Concentração Inibidora 50 , Modelos Moleculares , Mutação , Testes de Neutralização , SARS-CoV-2/química , SARS-CoV-2/classificação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
SARS-CoV-2 Omicron subvariants BA.2.12.1 and BA.4/5 have surged notably to become dominant in the United States and South Africa, respectively1,2. These new subvariants carrying further mutations in their spike proteins raise concerns that they may further evade neutralizing antibodies, thereby further compromising the efficacy of COVID-19 vaccines and therapeutic monoclonals. We now report findings from a systematic antigenic analysis of these surging Omicron subvariants. BA.2.12.1 is only modestly (1.8-fold) more resistant to sera from vaccinated and boosted individuals than BA.2. However, BA.4/5 is substantially (4.2-fold) more resistant and thus more likely to lead to vaccine breakthrough infections. Mutation at spike residue L452 found in both BA.2.12.1 and BA.4/5 facilitates escape from some antibodies directed to the so-called class 2 and 3 regions of the receptor-binding domain3. The F486V mutation found in BA.4/5 facilitates escape from certain class 1 and 2 antibodies but compromises the spike affinity for the viral receptor. The R493Q reversion mutation, however, restores receptor affinity and consequently the fitness of BA.4/5. Among therapeutic antibodies authorized for clinical use, only bebtelovimab retains full potency against both BA.2.12.1 and BA.4/5. The Omicron lineage of SARS-CoV-2 continues to evolve, successively yielding subvariants that are not only more transmissible but also more evasive to antibodies.
Assuntos
Anticorpos Antivirais , Deriva e Deslocamento Antigênicos , COVID-19 , Mutação , SARS-CoV-2 , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Deriva e Deslocamento Antigênicos/genética , Deriva e Deslocamento Antigênicos/imunologia , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Humanos , Imunização Secundária , Receptores Virais/metabolismo , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
The identification of the Omicron (B.1.1.529.1 or BA.1) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Botswana in November 20211 immediately caused concern owing to the number of alterations in the spike glycoprotein that could lead to antibody evasion. We2 and others3-6 recently reported results confirming such a concern. Continuing surveillance of the evolution of Omicron has since revealed the rise in prevalence of two sublineages, BA.1 with an R346K alteration (BA.1+R346K, also known as BA.1.1) and B.1.1.529.2 (BA.2), with the latter containing 8 unique spike alterations and lacking 13 spike alterations found in BA.1. Here we extended our studies to include antigenic characterization of these new sublineages. Polyclonal sera from patients infected by wild-type SARS-CoV-2 or recipients of current mRNA vaccines showed a substantial loss in neutralizing activity against both BA.1+R346K and BA.2, with drops comparable to that already reported for BA.1 (refs. 2,3,5,6). These findings indicate that these three sublineages of Omicron are antigenically equidistant from the wild-type SARS-CoV-2 and thus similarly threaten the efficacies of current vaccines. BA.2 also exhibited marked resistance to 17 of 19 neutralizing monoclonal antibodies tested, including S309 (sotrovimab)7, which had retained appreciable activity against BA.1 and BA.1+R346K (refs. 2-4,6). This finding shows that no authorized monoclonal antibody therapy could adequately cover all sublineages of the Omicron variant, except for the recently authorized LY-CoV1404 (bebtelovimab).
Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genéticaRESUMO
The COVID-19 pandemic has had widespread effects across the globe, and its causative agent, SARS-CoV-2, continues to spread. Effective interventions need to be developed to end this pandemic. Single and combination therapies with monoclonal antibodies have received emergency use authorization1-3, and more treatments are under development4-7. Furthermore, multiple vaccine constructs have shown promise8, including two that have an approximately 95% protective efficacy against COVID-199,10. However, these interventions were directed against the initial SARS-CoV-2 virus that emerged in 2019. The recent detection of SARS-CoV-2 variants B.1.1.7 in the UK11 and B.1.351 in South Africa12 is of concern because of their purported ease of transmission and extensive mutations in the spike protein. Here we show that B.1.1.7 is refractory to neutralization by most monoclonal antibodies against the N-terminal domain of the spike protein and is relatively resistant to a few monoclonal antibodies against the receptor-binding domain. It is not more resistant to plasma from individuals who have recovered from COVID-19 or sera from individuals who have been vaccinated against SARS-CoV-2. The B.1.351 variant is not only refractory to neutralization by most monoclonal antibodies against the N-terminal domain but also by multiple individual monoclonal antibodies against the receptor-binding motif of the receptor-binding domain, which is mostly due to a mutation causing an E484K substitution. Moreover, compared to wild-type SARS-CoV-2, B.1.351 is markedly more resistant to neutralization by convalescent plasma (9.4-fold) and sera from individuals who have been vaccinated (10.3-12.4-fold). B.1.351 and emergent variants13,14 with similar mutations in the spike protein present new challenges for monoclonal antibody therapies and threaten the protective efficacy of current vaccines.
Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/terapia , Evasão da Resposta Imune/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , COVID-19/prevenção & controle , COVID-19/virologia , Chlorocebus aethiops , Farmacorresistência Viral/imunologia , Células HEK293 , Humanos , Evasão da Resposta Imune/genética , Imunização Passiva , Pessoa de Meia-Idade , Modelos Moleculares , Mutação , Testes de Neutralização , Domínios Proteicos/imunologia , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas/imunologia , Células Vero , Soroterapia para COVID-19 , Tratamento Farmacológico da COVID-19 , Vacinas de mRNARESUMO
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.
Assuntos
Modelos Animais de Doenças , Gammainfluenzavirus , Cobaias , Infecções por Orthomyxoviridae , Thogotovirus , Animais , Humanos , Administração Intranasal , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Receptores ViraisRESUMO
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.
Assuntos
Infecções Bacterianas , Óxido de Zinco , Animais , Camundongos , Hidrogéis/farmacologia , Espécies Reativas de Oxigênio , Óxido de Zinco/farmacologia , Anti-Inflamatórios , Antibacterianos/farmacologiaRESUMO
The migration of epidermal stem cells (EpSCs) is critical for wound re-epithelization and wound healing. Recently, growth/differentiation factor-5 (GDF-5) was discovered to have multiple biological effects on wound healing; however, its role in EpSCs remains unclear. In this work, recombinant mouse GDF-5 (rmGDF-5) was found via live imaging in vitro to facilitate the migration of mouse EpSCs in a wound-scratch model. Western blot and real-time PCR assays demonstrated that the expression levels of RhoA and matrix metalloproteinase-9 (MMP9) were correlated with rmGDF-5 concentration. Furthermore, we found that rmGDF-5 stimulated mouse EpSC migration in vitro by regulating MMP9 expression at the mRNA and protein levels through the RhoA signalling pathway. Moreover, in a deep partial-thickness scald mouse model in vivo, GDF-5 was confirmed to promote EpSC migration and MMP9 expression via RhoA, as evidenced by the tracking of cells labelled with 5-bromo-2-deoxyuridine (BrdU). The current study showed that rmGDF-5 can promote mouse EpSC migration in vitro and in vivo and that GDF-5 can trigger the migration of EpSCs via RhoA-MMP9 signalling.
Assuntos
Movimento Celular/genética , Células Epidérmicas/metabolismo , Fator 5 de Diferenciação de Crescimento/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Células-Tronco/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Células Cultivadas , Expressão Gênica , Regulação da Expressão Gênica , Metaloproteinase 9 da Matriz/genética , Camundongos , RNA Mensageiro/genéticaRESUMO
Wound moisture management is very important in wound healing. Previous wound management has included dry healing and moist healing, and the theory of wound moisture balance is currently generally accepted. However, current studies have not reported which humidity is suitable for wound healing and how to appropriately use antibacterial compounds when the humidity is suitable. Our study explored the moisture balance of polyurethane foam dressings through a moisture balance test and constructed a safe and effective moisture balanced antibacterial dressing by loading lysozyme onto a polyurethane foam dressing. Wound healing experiments showed that the wound healing speed was the fastest when the humidity was 25%. In vivo and in vitro antibacterial experiments showed the superior antibacterial performance of the dressing after lysozyme loading. We loaded lysozyme on moisture balanced polyurethane dressings by means of dopamine adsorption, and the modified dressings were named PU/DA-LYS (polyurethane/dopamine-lysozyme). Experiments on wound healing in infected mice indicated that PU/DA-LYS helps fight infection while promoting wound healing. Cytotoxicity experiments and in vivo biological safety experiments indicated that PU/DA-LYS was safe for use. Our study found that the lysozyme loaded polyurethane dressing can provide appropriate wound moisture and prevent bacterial infection, which is a future developmental direction for wound dressings.
Assuntos
Bandagens , Muramidase , Animais , Antibacterianos/farmacologia , Camundongos , CicatrizaçãoRESUMO
Congenital diaphragmatic hernia (CDH) is a severe birth defect that is often accompanied by other congenital anomalies. Previous exome sequencing studies for CDH have supported a role of de novo damaging variants but did not identify any recurrently mutated genes. To investigate further the genetics of CDH, we analyzed de novo coding variants in 362 proband-parent trios including 271 new trios reported in this study. We identified four unrelated individuals with damaging de novo variants in MYRF (P = 5.3x10(-8)), including one likely gene-disrupting (LGD) and three deleterious missense (D-mis) variants. Eight additional individuals with de novo LGD or missense variants were identified from our other genetic studies or from the literature. Common phenotypes of MYRF de novo variant carriers include CDH, congenital heart disease and genitourinary abnormalities, suggesting that it represents a novel syndrome. MYRF is a membrane associated transcriptional factor highly expressed in developing diaphragm and is depleted of LGD variants in the general population. All de novo missense variants aggregated in two functional protein domains. Analyzing the transcriptome of patient-derived diaphragm fibroblast cells suggest that disease associated variants abolish the transcription factor activity. Furthermore, we showed that the remaining genes with damaging variants in CDH significantly overlap with genes implicated in other developmental disorders. Gene expression patterns and patient phenotypes support pleiotropic effects of damaging variants in these genes on CDH and other developmental disorders. Finally, functional enrichment analysis implicates the disruption of regulation of gene expression, kinase activities, intra-cellular signaling, and cytoskeleton organization as pathogenic mechanisms in CDH.
Assuntos
Variação Genética , Hérnias Diafragmáticas Congênitas/genética , Proteínas de Membrana/genética , Mutação , Fatores de Transcrição/genética , Pré-Escolar , Variações do Número de Cópias de DNA , Deficiências do Desenvolvimento/genética , Feminino , Cardiopatias Congênitas/genética , Hérnias Diafragmáticas Congênitas/metabolismo , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Proteínas de Membrana/metabolismo , Mutação de Sentido Incorreto , Fenótipo , Análise de Sequência de RNA , Síndrome , Fatores de Transcrição/metabolismo , Sequenciamento do Exoma , Sequenciamento Completo do GenomaRESUMO
Tumor-infiltrating PD-1hi dysfunctional CD8+ T cells have been identified in several tumors but largely unexplored in breast cancer (BC). Here we aimed to extensively explore PD-1hiCD8+ T cells in BC, focusing on the triple-negative BC (TNBC) subtype. Flow cytometry was used to study the phenotypes and functions of CD8+ T-cell subsets in peripheral blood and surgical specimens from treatment-naive BC patients. RNA-seq expression data generated to dissect the molecular features of tumoral PD-1neg, PD-1lo and PD-1hi CD8+ T cells. Further, the associations between tumoral PD-1hi CD8+ T cells and the clinicopathological features of 503 BC patients were explored. Finally, multiplexed immunohistochemistry (mIHC) was performed to evaluate in situ PD-1hiCD8+ T cells on the tissue microarrays (TMAs, n=328) for prognostic assessment and stratification of TNBC patients. PD-1hiCD8+ T cells found readily detectable in tumor tissues but rarely in peripheral blood. These cells shared the phenotypic and molecular features with exhausted and tissue-resident memory T cells (TRM) with a skewed TCR repertoire involvement. Interestingly, PD-1hiCD8+ T cells are in the state of exhaustion characterized by higher T-BET and reduced EOMES expression. PD-1hiCD8+ T cells found preferentially enriched within solid tumors, but predominant stromal infiltration of PD-1hiCD8+ T subset was associated with improved survival in TNBC patients. Taken together, tumoral PD-1hiCD8+ T-cell subpopulation in BC is partially exhausted, and their abundance signifies 'hot' immune status with favorable outcomes. Reinvigorating this population may provide further therapeutic opportunities in TNBC patients.
Assuntos
Biomarcadores Tumorais/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Receptor de Morte Celular Programada 1/imunologia , Neoplasias de Mama Triplo Negativas/imunologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Codificadores dos Receptores de Linfócitos T , Humanos , Memória Imunológica , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Pessoa de Meia-Idade , Fenótipo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Transcriptoma , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/cirurgia , Microambiente TumoralRESUMO
Body size is one of the most important attributes of a species, but the basic question of why and how each species reaches a different "right size" is still largely unknown. Herein, three phylogenetically closely related catfishes from Sisoridae, including one extraordinarily large-sized Bagarius yarrelli and two average-sized Glyptothorax macromaculatus and Oreoglanis setiger, were comparatively studied using RNA-Seq. Approximately 17,000 protein-coding genes were annotated for each of the three fishes, and 9509 genes were identified as high-confidence orthologous gene pairs. Comparative expressions uncovered a similar functional cluster about ribosome biogenesis was enriched in different tissues of the upregulated genes of Bagarius yarrelli. Moreover, differentially expressed genes and positively selected genes revealed that the glycolysis/pyruvate metabolism and cell cycle pathways have also greatly enhanced in this large-sized species. In total, 20 size-related candidate genes (including two growth modulators: the serine/threonine-protein kinases 3 (AKT3) and adaptor protein 1 (SH2B1), and a crucial pyruvate kinase (PKM2A)) were identified by multiplying comparative analyses along with gene functional screening, which would play major roles in enabling the large body size associated with Bagarius yarrelli and provide new insights into body size evolution. In conjunction with field observations and morphological comparisons, we hypothesize that habitat preferences promote size divergence of sisorids.
Assuntos
Tamanho Corporal , Peixes-Gato/genética , Evolução Molecular , Transcriptoma , Animais , Peixes-Gato/classificação , Peixes-Gato/crescimento & desenvolvimento , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismoRESUMO
A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of Pulsatilla saponin D, a potential antitumor constituent isolated from Pulsatilla chinensis in rat plasma. Rat plasma samples were pretreated by protein precipitation with methanol. The method validation was performed in accordance with US Food and Drug Administration guidelines and the results met the acceptance criteria. The method was successfully applied to assess the pharmacokinetics and oral bioavailability of Pulsatilla saponin D in rats.
Assuntos
Pulsatilla/química , Saponinas/sangue , Saponinas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/farmacocinética , Disponibilidade Biológica , Precipitação Química , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Masculino , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/análise , Ácido Oleanólico/farmacocinética , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Saponinas/administração & dosagem , Saponinas/análise , Sensibilidade e Especificidade , Estados Unidos , United States Food and Drug AdministrationRESUMO
Objective: Diagnosing tuberculosis (TB) can be particularly challenging in the absence of sputum for pulmonary tuberculosis cases and extrapulmonary TB (EPTB). This study evaluated the utility of nanopore-based targeted next-generation sequencing (tNGS) for diagnosing TB in tissue samples, and compared its efficacy with other established diagnostic methods. Methods: A total of 110 tissue samples from clinical cases were examined. The sensitivity and specificity of tNGS were benchmarked against a range of existing diagnostic approaches including hematoxylin and eosin (HE) staining in conjunction with acid-fast bacilli (AFB) detection, HE staining combined with PCR, HE staining paired with immunohistochemistry (IHC) using anti-MPT64, and the Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF) assay. Results: The sensitivity and specificity of tNGS were 88.2 and 94.1%, respectively. The respective sensitivities for HE staining combined with AFB, HE staining combined with PCR, HE staining combined with IHC using anti-MPT64, and Xpert MTB/RIF were 30.1, 49.5, 47.3, and 59.1%. The specificities for these methods were 82.4, 88.2, 94.1, and 94.1%, respectively. Analysis of drug resistance based on tNGS results indicated that 10 of 93 TB patients (10.75%) had potential drug resistance. Conclusion: Targeted next-generation sequencing achieved higher accuracy than other established diagnostic methods, and can play a crucial role in the rapid and accurate diagnosis of TB, including drug-resistant TB.
RESUMO
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.