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1.
Emerg Microbes Infect ; : 2401931, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39233480

RESUMEN

In 2022, the monkeypox virus (mpox virus, MPXV) exhibited global dissemination across six continents, representing a notable challenge owing to the scarcity of targeted antiviral interventions. Passive immunotherapy, such as the use of monoclonal antibodies (mAbs) and bispecific antibodies (bsAbs), has emerged as a promising option for antiviral regimens. Here, we generated several mAbs against M1R and B6R of MPXV, and subsequently characterized the antiviral activity of these antibodies both in vitro and in vivo. Two neutralizing mAbs, M1H11 and M3B2, targeting M1R, and one B6R-specific mAb, B7C9, were identified. They exhibited varying antiviral efficacy against MPXV and vaccinia virus (VACV) in vitro and orthopoxvirus infection in vivo. A cocktail comprising M1H11 and M3B2 demonstrated a superior protective effect in vivo. A bsAb, Bis-M1M3, was engineered by conjugating the fragment crystallizable (Fc) region of the human-mouse chimeric engineered M1H11 with the single-chain fragment variable (scFv) of M3B2. In mice challenged with MPXV, Bis-M1M3 showed a notable protective effects, including the absence of mortality. Analysis of neutralization mechanism showed that these mAbs and Bis-M1M3 exerted virus-neutralizing effects before the virus infects cells. In vivo pharmacokinetic experiments showed that Bis-M1M3 has a long half-life in rhesus macaques. This study provides crucial insights for further research on -broad-spectrum antiviral drugs against MPXV and other orthopoxviruses.

2.
Nanomaterials (Basel) ; 14(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38869581

RESUMEN

The recombination of charges and thermal excitation of carriers at the interface between methylammonium lead iodide perovskite (PVK) and the carbon electrode are crucial factors that affect the optoelectronic performance of carbon-based hole transport layer (HTL)-free perovskite photodetectors. In this work, a method was employed to introduce SnS quantum dots (QDs) on the back surface of perovskite, which passivated the defect states on the back surface of perovskite and addressed the energy-level mismatch issue between perovskite and carbon electrode. Performance testing of the QDs and the photodetector revealed that SnS QDs possess energy-level structures that are well matched with perovskite and have high absorption coefficients. The incorporation of these QDs into the interface layer effectively suppresses the dark current of the photodetector and greatly enhances the utilization of incident light. The experimental results demonstrate that the introduction of SnS QDs reduces the dark current by an order of magnitude compared to the pristine device at 0 V bias and increases the responsivity by 10%. The optimized photodetector exhibits a wide spectral response range (350 nm to 750 nm), high responsivity (0.32 A/W at 500 nm), and high specific detectivity (>1 × 1012 Jones).

3.
Exploration (Beijing) ; 4(3): 20230086, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38939869

RESUMEN

The ongoing mutations of the SARS-CoV-2 pose serious challenges to the efficacy of the available antiviral drugs, and new drugs with fantastic efficacy are always deserved investigation. Here, a nanobody called IBT-CoV144 is reported, which exhibits broad neutralizing activity against SARS-CoV-2 by inducing the conformation of spike trimer dimers. IBT-CoV144 was isolated from an immunized alpaca using the RBD of wild-type SARS-CoV-2, and it showed strong cross-reactive binding and neutralizing potency against diverse SARS-CoV-2 variants, including Omicron subvariants. Moreover, the prophylactically and therapeutically intranasal administration of IBT-CoV144 confers fantastic protective efficacy against the challenge of Omicron BA.1 variant in BALB/c mice model. The structure analysis of the complex between spike (S) protein, conducted using Cryo-EM, revealed a special conformation known as the trimer dimers. This conformation is formed by two trimers, with six RBDs in the "up" state and bound by six VHHs. IBT-CoV144 binds to the lateral region of the RBD on the S protein, facilitating the aggregation of S proteins. This aggregation results in steric hindrance, which disrupts the recognition of the virus by ACE2 on host cells. The discovery of IBT-CoV144 will provide valuable insights for the development of advanced therapeutics and the design of next-generation vaccines.

4.
Biosensors (Basel) ; 14(6)2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38920609

RESUMEN

Lateral flow immunoassays (LFIAs) are recognized for their practicality in homecare and point-of-care testing, owing to their simplicity, cost-efficiency, and rapid visual readouts. Despite these advantages, LFIAs typically fall short in sensitivity, particularly in detecting viruses such as SARS-CoV-2, thus limiting their broader application. In response to this challenge, we have innovated an approach to substantially enhance LFIA sensitivity. This involves the integration of a water-soluble dextran-methacrylate polymer wall with a 15% grafting degree positioned between the test and control lines on the LFIA strip. This novel modification significantly improved the sensitivity of the assay, achieving detection limits as low as 50 pg mL-1 and enhancing the sensitivity by 5-20-fold relative to existing LFIA kits available on the market. Furthermore, our developed LFIA kit (WSPW-LFIA) demonstrated exceptional specificity for SARS-CoV-2. Coupled with a straightforward fabrication process and robust stability, the WSPW-LFIA represents a promising advancement for real-time in vitro diagnosis across a spectrum of diseases.


Asunto(s)
COVID-19 , Polímeros , SARS-CoV-2 , SARS-CoV-2/inmunología , Humanos , COVID-19/diagnóstico , Inmunoensayo/métodos , Polímeros/química , Técnicas Biosensibles , Antígenos Virales/análisis , Agua , Sensibilidad y Especificidad , Límite de Detección , Prueba Serológica para COVID-19/métodos , Dextranos
5.
Immunol Res ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829493

RESUMEN

Monkeypox cases continue to increase globally, and there is an urgent need to develop a highly effective vaccine against monkeypox. This study investigated the binding and authentic-virus neutralizing activities of sera from mice immunized with EEV (extracellularly enveloped viruses) antigens B6R and A35R, and IMV (intrinsic material viruses) antigens M1R, A29L, E8L, and H3L against monkeypox virus. The results showed that immunizations of A35R and E8L could only induce lower titers of binding antibodies, in contrast, immunization of M1R induced the highest titers of binding antibodies, while immunization of B6R, H3L, and A29L induced moderate titers of binding antibodies. For the live monkeypox virus neutralization assay, the results showed that immunization with two doses of EEV antigen B6R did not effectively induce humoral immune responses to neutralize monkeypox live virus, immunization with EEV-A35R only induced weak monkeypox-neutralizing antibodies. In contrast, the immunization of the four types of monkeypox virus IMV antigens can all induce neutralizing antibodies against authentic monkeypox virus, among them, A29L and H3L induced the highest neutralizing antibody titers. The results of this study provide important references for the selection of antigens in the development of the next generation of monkeypox vaccines.

6.
Nat Commun ; 15(1): 4488, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802350

RESUMEN

Understanding of infection dynamics is important for public health measures against monkeypox virus (MPXV) infection. Herein, samples from multiple body sites and environmental fomites of 77 acute MPXV infections (HIV co-infection: N = 42) were collected every two to three days and used for detection of MPXV DNA, surface protein specific antibodies and neutralizing titers. Skin lesions show 100% positivity rate of MPXV DNA, followed by rectum (88.16%), saliva (83.78%) and oropharynx (78.95%). Positivity rate of oropharynx decreases rapidly after 7 days post symptom onset (d.p.o), while the rectum and saliva maintain a positivity rate similar to skin lesions. Viral dynamics are similar among skin lesions, saliva and oropharynx, with a peak at about 6 d.p.o. In contrast, viral levels in the rectum peak at the beginning of symptom onset and decrease rapidly thereafter. 52.66% of environmental fomite swabs are positive for MPXV DNA, with highest positivity rate (69.89%) from air-conditioning air outlets. High seropositivity against A29L (100%) and H3L (94.74%) are detected, while a correlation between IgG endpoint titers and neutralizing titers is only found for A29L. Most indexes are similar between HIV and Non-HIV participants, while HIV and rectitis are associated with higher viral loads in rectum.


Asunto(s)
Anticuerpos Antivirales , Monkeypox virus , Mpox , Esparcimiento de Virus , Humanos , Masculino , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Estudios Prospectivos , Adulto , Monkeypox virus/inmunología , Mpox/inmunología , Mpox/virología , Mpox/epidemiología , Saliva/virología , Saliva/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Persona de Mediana Edad , Estudios Longitudinales , ADN Viral , Orofaringe/virología , Orofaringe/inmunología , Coinfección/inmunología , Coinfección/virología , Coinfección/epidemiología , Carga Viral , Fómites/virología
7.
Microbiol Spectr ; 12(4): e0181623, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38385650

RESUMEN

Human adenovirus (HAdV) infects the respiratory system, thus posing a threat to health. However, immunodiagnostic reagents for human adenovirus are limited. This study aimed to develop efficient diagnostic reagents based on monoclonal antibodies for diagnosing various human adenovirus infections. Evolutionary and homology analyses of various human adenoviral antigen genes revealed highly conserved antigenic fragments. The prokaryotic expression system was applied to recombinant penton, hexon, and IVa2 conserved fragments of adenovirus, which were injected into BALB/c mice to prepare human adenovirus-specific monoclonal antibodies. Enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence assay (IFA), and Western blotting were used to determine the immune specificity of the monoclonal antibodies. Indirect ELISA showed that monoclonal antibodies 1F10, 8D3, 4A1, and 9B2 were specifically bound to HAdV-3 and HAdV-55 and revealed high sensitivity and low detection limits for various human adenoviruses. Western blotting showed that 1F10 and 8D3 specifically recognized various human adenovirus types, including HAdV-1, HAdV-2, HAdV-3, HAdV-4, HAdV-5, HAdV-7, HAdV-21, and HAdV-55, and 4A1 specifically recognized HAdV-1, HAdV-2, HAdV-3, HAdV-5, HAdV-7, HAdV-21, and HAdV-55. IFAs showed that 1F10, 8D3, and 4A1 exhibited highly selective localization to A549 cells infected with HAdV-3 and HAdV-55. Finally, two antibody pairs that could detect hexon antigens HAdV-3 and HAdV-55 at low concentrations were developed. The monoclonal antibodies developed in this study show potential for detecting human adenoviruses. IMPORTANCE: In this study, we selected the three most conserved antigenic fragments of human adenovirus to prepare a murine monoclonal antibody for the first time, and human adenovirus antigenic fragments with heretofore unheard of degrees of conservatism were isolated. The three monoclonal antibodies with the ability to recognize human respiratory adenovirus over a broad spectrum were screened by hybridoma and monoclonal antibody preparation. Human adenovirus infections are serious; however, therapeutic drugs and diagnostic reagents are scarce. Thus, to reduce the serious consequences of human viral infections and adenovirus pneumonitis, early diagnosis of infection is required. The present study provides three monoclonal antibodies capable of recognizing a wide range of human adenoviruses, thereby offering guidance for subsequent research and development.


Asunto(s)
Infecciones por Adenovirus Humanos , Adenovirus Humanos , Humanos , Animales , Ratones , Anticuerpos Monoclonales , Anticuerpos Antivirales , Adenovirus Humanos/genética , Serogrupo , Proteínas de la Cápside/genética
9.
Signal Transduct Target Ther ; 9(1): 40, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355661

RESUMEN

Emerging and recurrent infectious diseases caused by human coronaviruses (HCoVs) continue to pose a significant threat to global public health security. In light of this ongoing threat, the development of a broad-spectrum drug to combat HCoVs is an urgently priority. Herein, we report a series of anti-pan-coronavirus ssDNA aptamers screened using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). These aptamers have nanomolar affinity with the nucleocapsid protein (NP) of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and also show excellent binding efficiency to the N proteins of both SARS, MERS, HCoV-OC43 and -NL63 with affinity KD values of 1.31 to 135.36 nM. Such aptamer-based therapeutics exhibited potent antiviral activity against both the authentic SARS-CoV-2 prototype strain and the Omicron variant (BA.5) with EC50 values at 2.00 nM and 41.08 nM, respectively. The protein docking analysis also evidenced that these aptamers exhibit strong affinities for N proteins of pan-coronavirus and other HCoVs (-229E and -HKU1). In conclusion, we have identified six aptamers with a high pan-coronavirus antiviral activity, which could potentially serve as an effective strategy for preventing infections by unknown coronaviruses and addressing the ongoing global health threat.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Proteínas de la Nucleocápside/genética , Antivirales/farmacología
10.
Adv Mater ; 36(9): e2305378, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37931029

RESUMEN

The recent prevalence of monkeypox has led to the declaration of a Public Health Emergency of International Concern. Monkeypox lesions are typically ulcers or pustules (containing high titers of replication-competent virus) in the skin and mucous membranes, which allow monkeypox virus to transmit predominantly through intimate contact. Currently, effective clinical treatments for monkeypox are lacking, and strategies for blocking virus transmission are fraught with drawbacks. Herein, this work constructs a biomimetic nanotemplate (termed TBD@M NPs) with macrophage membranes as the coat and polymeric nanoparticles loading a versatile aggregation-induced emission featured photothermal molecule TPE-BT-DPTQ as the core. In a surrogate mouse model of monkeypox (vaccinia-virus-infected tail scarification model), intravenously injected TBD@M NPs show precise tracking and near-infrared region II fluorescence imaging of the lesions. Upon 808 nm laser irradiation, the virus is eliminated by the photothermal effect and the infected wound heals rapidly. More importantly, the inoculation of treated lesion tissue suspensions does not trigger tail infection or inflammatory activation in healthy mice, indicating successful blockage of virus transmission. This study demonstrates for the first time monkeypox theranostics using nanomedicine, and may bring a new insight into the development of a viable strategy for monkeypox management in clinical trials.


Asunto(s)
Mpox , Nanopartículas , Animales , Ratones , Terapia Fototérmica , Biomimética , Macrófagos , Nanopartículas/uso terapéutico
11.
Microbiol Spectr ; 12(1): e0071923, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38059628

RESUMEN

IMPORTANCE: Globally, the increasing number of hypervirulent Klebsiella pneumoniae (hvKp) and carbapenem-resistant Kp (CR-Kp) infections poses a huge public health challenge with high morbidity and mortality. Worrisomely, due to the mobility of elements carrying virulence and drug-resistance genes, the increasing prevalence of CR-hvKp has also been found with an overwhelming mortality rate in recent years. However, the current detection methods for hvKp and CR-Kp have many disadvantages, such as long turnaround time, complex operation, low sensitivity, and specificity. Herein, a more sensitive, rapid, single-reaction, and multiplex quantitative real-time PCR was developed and validated to differentiate the circulating lineages of Kp with excellent performance in sensitivity and specificity, providing a useful tool for the differential diagnosis and the surveillance of the circulating Kp.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Humanos , Klebsiella pneumoniae/genética , Infecciones por Klebsiella/diagnóstico , Infecciones por Klebsiella/epidemiología , Carbapenémicos/farmacología , Virulencia/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Antibacterianos/farmacología
12.
Nat Commun ; 14(1): 8241, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38086870

RESUMEN

The first local mpox outbreak in Guangdong Province, China occurred in June 2023. However, epidemiological data have failed to quickly identify the source and transmission of the outbreak. Here, phylogeny and molecular evolution of 10 monkeypox virus (MPXV) genome sequences from the Guangdong outbreak were characterized, revealing local silent transmissions that may have occurred in Guangdong whose mpox outbreaks suggested a molecular epidemiological correlation with Portugal and several regions of China during the same period. The lineage IIb C.1, which includes all 10 MPXV from Guangdong, shows consistent temporal continuity in both phylogenetic characteristics and unique molecular evolutionary mutation spectrum, reflected in the continuous increase of single nucleotide polymorphisms (SNPs) and shared mutations over time. Compared with the Japan MPXV, the Guangdong MPXV showed higher genomic nucleotide differences and separated 14 shared mutations from the B.1 lineage, comprising 6 non-synonymous mutations in genes linked to host regulation, virus infection, and virus life cycle. The unique mutation spectrum with temporal continuity in IIb C.1, related to apolipoprotein B mRNA-editing catalytic polypeptide-like 3, promotes rapid viral evolution and diversification. The findings contribute to understanding the ongoing mpox outbreak in China and offer insights for developing joint prevention and control strategies.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Filogenia , Monkeypox virus/genética , Brotes de Enfermedades , Evolución Molecular
13.
Appl Environ Microbiol ; 89(10): e0095623, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37815340

RESUMEN

Klebsiella pneumoniae is a ubiquitous human pathogen, and its clinical treatment faces two major challenges: multidrug resistance and the pathogenesis of hypervirulent K. pneumoniae. The discovery and study of conditionally essential (CE) genes that can function as potential antimicrobial targets has always been a research concern due to their restriction in the development of novel antibiotics. However, the lack of essential functional genomic data has hampered the study of the mechanisms of essential genes related to antimicrobial susceptibility. In this study, we developed a pooled CE genes mobile clustered regularly interspaced short palindromic repeat (CRISPR) interference screening method (Mobile-CRISPRi-seq) for K. pneumoniae to identify genes that play critical roles in antimicrobial fitness in vitro and host immunity in vivo. Targeting 870 predicted CE genes in K. pneumoniae, Mobile-CRISPRi-seq uncovered the depletion of tetrahydrofolate synthesis pathway genes folB and folP under trimethoprim pressure. Our screening also identified genes waaE and fldA related to polymyxin and ß-lactam susceptibility by applying a screening strategy based on Mobile-CRISPRi-seq and comparative genomics. Furthermore, using a mouse infection model and Mobile-CRISPRi-seq, multiple virulence genes were identified, and among these genes, pal, yciS, and ribB were demonstrated to contribute to the pathogenesis of K. pneumoniae. This study provides a simple, rapid, and effective platform for screening potential antimicrobial targets and virulence genes in K. pneumoniae, and this broadly applicable system can be expanded for high-throughput functional gene study in multiple pathogenic bacteria, especially in gram-negative bacteria. IMPORTANCE The discovery and investigation of conditionally essential (CE) genes that can function as potential antimicrobial targets has always been a research concern because of the restriction of antimicrobial targets in the development of novel antibiotics. In this study, we developed a pooled CE gene-wide mobile clustered regularly interspaced short palindromic repeat (CRISPR) interference sequencing (Mobile-CRISPRi-seq) strategy in Klebsiella pneumoniae to identify genes that play critical roles in the fitness of antimicrobials in vitro and host immunity in vivo. The data suggest a robust tool to screen for loss-of-function phenotypes in a pooled gene knockdown library in K. pneumoniae, and Mobile-CRISPRi-seq may be expanded to multiple bacteria for screening and identification of genes with crucial roles in the fitness of antimicrobials and hosts.


Asunto(s)
Genes Esenciales , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Virulencia/genética , Técnicas de Silenciamiento del Gen , Bacterias/genética , Antibacterianos/farmacología
15.
Front Cell Dev Biol ; 11: 1229393, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37576600

RESUMEN

The coronavirus disease 2019 (COVID-19) was a global endemic that continues to cause a large number of severe illnesses and fatalities. There is increasing evidence that non-coding RNAs (ncRNAs) are crucial regulators of viral infection and antiviral immune response and the role of non-coding RNAs in SARS-CoV-2 infection has now become the focus of scholarly inquiry. After SARS-CoV-2 infection, some ncRNAs' expression levels are regulated to indirectly control the expression of antiviral genes and viral gene replication. However, some other ncRNAs are hijacked by SARS-CoV-2 in order to help the virus evade the immune system by suppressing the expression of type I interferon (IFN-1) and controlling cytokine levels. In this review, we summarize the recent findings of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) among non-coding RNAs in SARS-CoV-2 infection and antiviral response, discuss the potential mechanisms of actions, and prospects for the detection, treatment, prevention and future directions of SARS-CoV-2 infection research.

16.
Biosystems ; 231: 104970, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37442364

RESUMEN

Full-length nucleotide sequences of avian influenza A virus neuraminidase coding region (20,631 sequences) were analyzed and compared with those isolated from viruses infecting human and swine (63,750 sequences). If in fourfold degenerate sites there is asymmetric A-bias that may be more or less asymmetric depending on the type of neuraminidase and the host, than in twofold degenerate sites from third codon positions there is a strong asymmetric U-bias in coding regions of N4, N5, and N8 isolated from viruses infecting birds, as well as in those of N1 and N2 isolated from viruses infecting human, swine, and birds, while in coding regions of N9 isolated from birds, there is surprisingly strong C-bias, and in sequences of N3, N6, and N7 the usage of C is quite close to the level of U. Revealed stabilization of both U and C in twofold degenerate sites is the evidence of frequent changes in mutational pressure direction. Asymmetric mutational pressure was one of the sources of amino acid replacements that resulted in an equal percentage of sites with appeared and disappeared linear B-cell epitopes in N1, N2, N4, and N5 (33.62-35.33% vs. 32.41-36.45%, respectively), and controlled by the immune pressure it resulted in a stronger tendency to disappear for B-cell epitopes of N3, N6, N7, N8, and N9 of avian viruses (8.74-28.77% vs. 28.96-38.89%). The lack of correlation between nucleotide usages in fourfold and twofold degenerate sites for three nucleotides, except U, is a strong evidence of mutational pressure theory.


Asunto(s)
Virus de la Influenza A , Neuraminidasa , Animales , Humanos , Porcinos , Neuraminidasa/genética , Neuraminidasa/química , Epítopos de Linfocito B/genética , Mutación , Virus de la Influenza A/genética , Aves
18.
Emerg Microbes Infect ; 12(2): 2223669, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37288876

RESUMEN

The worldwide outbreak of the monkeypox virus (MPXV) has become a "Public Health Emergency of International Concern" (PHEIC). Severe monkeypox virus infection can be fatal, however, effective therapeutic methods are yet to be developed. Mice were immunized with A35R protein and A29L protein of MPXV, and the binding and neutralizing activities of the immune sera against poxvirus-associated antigens and viruses were identified. A29L protein and A35R protein-specific monoclonal antibodies (mAbs) were generated and their antiviral activities of these mAbs were characterized in vitro and in vivo. Immunization with the MPXV A29L protein and A35R protein induced neutralizing antibodies against the orthopoxvirus in mice. None of the mAbs screened in this study against A35R could effectively neutralize the vaccinia virus (VACV), while three mAbs against A29L protein, 9F8, 3A1 and 2D1 were confirmed to have strong broad binding and neutralizing activities against orthopoxvirus, among which 9F8 showed the best neutralizing activity. 9F8, 3A1, and 2D1 recognized different epitopes on MPXV A29L protein, showing synergistic antiviral activity in vitro against the VACV Tian Tan and WR strains; the best activity was observed when the three antibodies were combined. In the vivo antiviral prophylactic and therapeutic experiments, 9F8 showed complete protective activity, whereas 3A1 and 2D1 showed partial protective activity. Similarly, the three antibodies showed synergistic antiviral protective activity against the two VACVs. In conclusion, three mAbs recognized different epitopes on MPXV A29L protein were developed and showed synergistic effects against orthopoxvirus.


Asunto(s)
Enfermedades Transmisibles , Mpox , Orthopoxvirus , Animales , Ratones , Anticuerpos Neutralizantes , Orthopoxvirus/genética , Epítopos , Anticuerpos Antivirales , Proteínas Virales/genética , Virus Vaccinia , Monkeypox virus , Anticuerpos Monoclonales
19.
Viruses ; 15(6)2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37376597

RESUMEN

The monoclonal antibody (mAb)-based treatment is a highly valued therapy against COVID-19, especially for individuals who may not have strong immune responses to the vaccine. However, with the arrival of the Omicron variant and its evolving subvariants, along with the occurrence of remarkable resistance of these SARS-CoV-2 variants to the neutralizing antibodies, mAbs are facing tough challenges. Future strategies for developing mAbs with improved resistance to viral evasion will involve optimizing the targeting epitopes on SARS-CoV-2, enhancing the affinity and potency of mAbs, exploring the use of non-neutralizing antibodies that bind to conserved epitopes on the S protein, as well as optimizing immunization regimens. These approaches can improve the viability of mAb therapy in the fight against the evolving threat of the coronavirus.


Asunto(s)
COVID-19 , Humanos , COVID-19/terapia , SARS-CoV-2 , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/uso terapéutico , Epítopos , Glicoproteína de la Espiga del Coronavirus , Anticuerpos Antivirales/uso terapéutico
20.
J Med Virol ; 95(1): e28106, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36039848

RESUMEN

The discovery of broadly neutralizing monoclonal antibodies against influenza viruses has raised hope for the successful development of new antiviral drugs. However, due to the speed and variety of mutations in influenza viruses, single-component antibodies that recognize specific epitopes are susceptible to viral escape and have limited efficacy when administration is delayed. Hence, it is necessary to develop alternative strategies with better antiviral activity. Influenza B virus infection can cause severe illness in children and the elderly. Commonly used anti-influenza drugs have low clinical efficacy against influenza B virus. In this study, we investigated the antiviral efficacy of combinations of representative monoclonal antibodies targeting different antigenic epitopes against the influenza B virus. We found that combinations of antibodies recognizing the hemagglutinin (HA) head and stem regions showed a stronger neutralizing activity than single antibodies and other antibody combinations in vitro. In addition, we found that pair-wise combinations of antibodies recognizing the HA head region, HA stem region, and neuraminidase enzyme-activated region showed superior antiviral activity than single antibodies in both mouse and ferret in vivo protection assays. Notably, these antibody combinations still displayed good antiviral efficacy when treatment was delayed. Mechanistic studies further revealed that combining antibodies recognizing different epitope regions resulted in extremely strong antibody-dependent cell-mediated cytotoxicity, which may partly explain their superior antiviral effects. Together, the findings of this study provide new avenues for the development of better antiviral drugs and vaccines against influenza viruses.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Ratones , Humanos , Epítopos , Virus de la Influenza B , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Anticuerpos ampliamente neutralizantes , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Hurones , Hemaglutininas , Anticuerpos Monoclonales/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico
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