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1.
N Engl J Med ; 389(9): 808-819, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37646678

RESUMO

BACKGROUND: Population screening of asymptomatic persons with Epstein-Barr virus (EBV) DNA or antibodies has improved the diagnosis of nasopharyngeal carcinoma and survival among affected persons. However, the positive predictive value of current screening strategies is unsatisfactory even in areas where nasopharyngeal carcinoma is endemic. METHODS: We designed a peptide library representing highly ranked B-cell epitopes of EBV coding sequences to identify novel serologic biomarkers for nasopharyngeal carcinoma. After a retrospective case-control study, the performance of the novel biomarker anti-BNLF2b total antibody (P85-Ab) was validated through a large-scale prospective screening program and compared with that of the standard two-antibody-based screening method (EBV nuclear antigen 1 [EBNA1]-IgA and EBV-specific viral capsid antigen [VCA]-IgA). RESULTS: P85-Ab was the most promising biomarker for nasopharyngeal carcinoma screening, with high sensitivity (94.4%; 95% confidence interval [CI], 86.4 to 97.8) and specificity (99.6%; 95% CI, 97.8 to 99.9) in the retrospective case-control study. Among the 24,852 eligible participants in the prospective cohort, 47 cases of nasopharyngeal carcinoma (38 at an early stage) were identified. P85-Ab showed higher sensitivity than the two-antibody method (97.9% vs. 72.3%; ratio, 1.4 [95% CI, 1.1 to 1.6]), higher specificity (98.3% vs. 97.0%; ratio, 1.01 [95% CI, 1.01 to 1.02]), and a higher positive predictive value (10.0% vs. 4.3%; ratio, 2.3 [95% CI, 1.8 to 2.8]). The combination of P85-Ab and the two-antibody method markedly increased the positive predictive value to 44.6% (95% CI, 33.8 to 55.9), with sensitivity of 70.2% (95% CI, 56.0 to 81.4). CONCLUSIONS: Our results suggest that P85-Ab is a promising novel biomarker for nasopharyngeal carcinoma screening, with higher sensitivity, specificity, and positive predictive value than the standard two-antibody method. (Funded by the National Key Research and Development Program of China and others; ClinicalTrials.gov number, NCT04085900.).


Assuntos
Anticorpos Antivirais , Detecção Precoce de Câncer , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas Virais , Humanos , Anticorpos Antivirais/imunologia , Estudos de Casos e Controles , Herpesvirus Humano 4/imunologia , Imunoglobulina A , Programas de Rastreamento , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/virologia , Estudos Prospectivos , Estudos Retrospectivos , Biomarcadores/análise , Proteínas Virais/imunologia , Epitopos/imunologia
2.
Lancet ; 403(10429): 813-823, 2024 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-38387470

RESUMO

BACKGROUND: Hepatitis E virus (HEV) is a frequently overlooked causative agent of acute hepatitis. Evaluating the long-term durability of hepatitis E vaccine efficacy holds crucial importance. METHODS: This study was an extension to a randomised, double-blind, placebo-controlled, phase-3 clinical trial of the hepatitis E vaccine conducted in Dontai County, Jiangsu, China. Participants were recruited from 11 townships in Dongtai County. In the initial trial, a total of 112 604 healthy adults aged 16-65 years were enrolled, stratified according to age and sex, and randomly assigned in a 1:1 ratio to receive three doses of hepatitis E vaccine or placebo intramuscularly at month 0, month 1, and month 6. A sensitive hepatitis E surveillance system including 205 clinical sentinels, covering the entire study region, was established and maintained for 10 years after vaccination. The primary outcome was the per-protocol efficacy of hepatitis E virus vaccine to prevent confirmed hepatitis E occurring at least 30 days after administration of the third dose. Throughout the study, the participants, site investigators, and laboratory staff remained blinded to the treatment assignments. This study is registered with ClinicalTrials.gov (NCT01014845). FINDINGS: During the 10-year study period from Aug 22, 2007, to Oct 31, 2017, 90 people with hepatitis E were identified; 13 in the vaccine group (0·2 per 10 000 person-years) and 77 in the placebo group (1·4 per 10 000 person-years), corresponding to a vaccine efficacy of 83·1% (95% CI 69·4-91·4) in the modified intention-to-treat analysis and 86·6% (73·0 to 94·1) in the per-protocol analysis. In the subsets of participants assessed for immunogenicity persistence, of those who were seronegative at baseline and received three doses of hepatitis E vaccine, 254 (87·3%) of 291 vaccinees in Qindong at the 8·5-year mark and 1270 (73·0%) of 1740 vaccinees in Anfeng at the 7·5-year mark maintained detectable concentrations of antibodies. INTERPRETATION: Immunisation with this hepatitis E vaccine offers durable protection against hepatitis E for up to 10 years, with vaccine-induced antibodies against HEV persisting for at least 8·5 years. FUNDING: National Natural Science Foundation of China, Fujian Provincial Natural Science Foundation, Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, and the Fundamental Research Funds for the Central Universities.


Assuntos
Hepatite E , Vacinas contra Hepatite Viral , Adulto , Humanos , Anticorpos Antivirais , Hepatite E/prevenção & controle , Vacinação
3.
J Virol ; 98(8): e0192923, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39078152

RESUMO

Hepatitis B virus (HBV) expresses co-terminal large (L), middle (M), and small (S) envelope proteins containing preS1/preS2/S, preS2/S, and S domain alone, respectively. S and preS1 domains mediate sequential virion attachment to heparan sulfate proteoglycans and sodium taurocholate cotransporting polypeptide (NTCP), respectively, which can be blocked by anti-S and anti-preS1 antibodies. How anti-preS2 antibodies neutralize HBV infectivity remains enigmatic. The late stage of chronic HBV infection often selects for mutated preS2 translation initiation codon to prevent M protein expression, or in-frame preS2 deletions to shorten both L and M proteins. When introduced to infectious clone of genotype C or D, both M-minus mutations and most 5' preS2 deletions sustained virion production. Such mutant progeny viral particles were infectious in NTCP-reconstituted HepG2 cells. Neutralization experiments were performed on the genotype D clone. Although remaining susceptible to anti-preS1 and anti-S neutralizing antibodies, M-minus mutants were only partially neutralized by two anti-preS2 antibodies tested while preS2 deletion mutants were resistant. By infection experiments using viral particles with lost versus increased M protein expression, or a neutralization escaping preS2 deletion only present on L or M protein, we found that both full-length L and M proteins contributed to virus neutralization by the two anti-preS2 antibodies. Thus, immune escape could be a driving force for the selection of M-minus mutations, and especially preS2 deletions. The fact that both L and M proteins could mediate neutralization by anti-preS2 antibodies may shed light on the underlying molecular mechanism.IMPORTANCEThe large (L), middle (M), and small (S) envelope proteins of hepatitis B virus (HBV) contain preS1/preS2/S, preS2/S, and S domain alone, respectively. The discovery of heparan sulfate proteoglycans and sodium taurocholate cotransporting polypeptide (NTCP) as the low- and high-affinity HBV receptors could explain neutralizing potential of anti-S and anti-preS1 antibodies, respectively, but how anti-preS2 neutralizing antibodies work remains enigmatic. In this study, we found two M-minus mutants in the context of genotype D partially escaped two anti-preS2 neutralizing antibodies in NTCP-reconstituted HepG2 cells, while several naturally occurring preS2 deletion mutants escaped both antibodies. By point mutations to eliminate or enhance M protein expression, and by introducing preS2 deletion selectively to L or M protein, we found binding of anti-preS2 antibodies to both L and M proteins contributed to neutralization of wild-type HBV infectivity. Our finding may shed light on the possible mechanism(s) whereby anti-preS2 antibodies neutralize HBV infectivity.


Assuntos
Anticorpos Neutralizantes , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Proteínas do Envelope Viral , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , Humanos , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/genética , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/genética , Anticorpos Neutralizantes/imunologia , Células Hep G2 , Deleção de Sequência , Simportadores/imunologia , Simportadores/genética , Precursores de Proteínas/imunologia , Precursores de Proteínas/genética , Anticorpos Anti-Hepatite B/imunologia , Hepatite B/imunologia , Hepatite B/virologia , Genótipo , Evasão da Resposta Imune , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/imunologia , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Vírion/imunologia
4.
Proc Natl Acad Sci U S A ; 119(34): e2204256119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35972965

RESUMO

Antibody therapeutics for the treatment of COVID-19 have been highly successful. However, the recent emergence of the Omicron variant has posed a challenge, as it evades detection by most existing SARS-CoV-2 neutralizing antibodies (nAbs). Here, we successfully generated a panel of SARS-CoV-2/SARS-CoV cross-neutralizing antibodies by sequential immunization of the two pseudoviruses. Of the potential candidates, we found that nAbs X01, X10, and X17 offer broad neutralizing potential against most variants of concern, with X17 further identified as a Class 5 nAb with undiminished neutralization against the Omicron variant. Cryo-electron microscopy structures of the three antibodies together in complex with each of the spike proteins of the prototypical SARS-CoV, SARS-CoV-2, and Delta and Omicron variants of SARS-CoV-2 defined three nonoverlapping conserved epitopes on the receptor-binding domain. The triple-antibody mixture exhibited enhanced resistance to viral evasion and effective protection against infection of the Beta variant in hamsters. Our findings will aid the development of antibody therapeutics and broad vaccines against SARS-CoV-2 and its emerging variants.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , SARS-CoV-2 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Sequência Conservada , Cricetinae , Microscopia Crioeletrônica , Epitopos/imunologia , Humanos , Camundongos , Testes de Neutralização , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
5.
Proc Natl Acad Sci U S A ; 119(32): e2202371119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917353

RESUMO

Epstein-Barr virus (EBV) infects more than 90% of the world's adult population and accounts for a significant cancer burden of epithelial and B cell origins. Glycoprotein B (gB) is the primary fusogen essential for EBV entry into host cells. Here, we isolated two EBV gB-specific neutralizing antibodies, 3A3 and 3A5; both effectively neutralized the dual-tropic EBV infection of B and epithelial cells. In humanized mice, both antibodies showed effective protection from EBV-induced lymphoproliferative disorders. Cryoelectron microscopy analyses identified that 3A3 and 3A5 bind to nonoverlapping sites on domains D-II and D-IV, respectively. Structure-based mutagenesis revealed that 3A3 and 3A5 inhibit membrane fusion through different mechanisms involving the interference with gB-cell interaction and gB activation. Importantly, the 3A3 and 3A5 epitopes are major targets of protective gB-specific neutralizing antibodies elicited by natural EBV infection in humans, providing potential targets for antiviral therapies and vaccines.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Proteínas Virais , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/química , Anticorpos Antivirais/isolamento & purificação , Anticorpos Antivirais/uso terapêutico , Microscopia Crioeletrônica , Infecções por Vírus Epstein-Barr/prevenção & controle , Infecções por Vírus Epstein-Barr/terapia , Herpesvirus Humano 4/imunologia , Humanos , Fusão de Membrana , Camundongos , Proteínas Virais/imunologia
6.
BMC Bioinformatics ; 25(1): 35, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38254030

RESUMO

BACKGROUND: Natural proteins occupy a small portion of the protein sequence space, whereas artificial proteins can explore a wider range of possibilities within the sequence space. However, specific requirements may not be met when generating sequences blindly. Research indicates that small proteins have notable advantages, including high stability, accurate resolution prediction, and facile specificity modification. RESULTS: This study involves the construction of a neural network model named TopoProGenerator(TPGen) using a transformer decoder. The model is trained with sequences consisting of a maximum of 65 amino acids. The training process of TopoProGenerator incorporates reinforcement learning and adversarial learning, for fine-tuning. Additionally, it encompasses a stability predictive model trained with a dataset comprising over 200,000 sequences. The results demonstrate that TopoProGenerator is capable of designing stable small protein sequences with specified topology structures. CONCLUSION: TPGen has the ability to generate protein sequences that fold into the specified topology, and the pretraining and fine-tuning methods proposed in this study can serve as a framework for designing various types of proteins.


Assuntos
Aminoácidos , Fontes de Energia Elétrica , Sequência de Aminoácidos , Idioma , Aprendizagem
7.
J Hepatol ; 80(6): 858-867, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38336347

RESUMO

BACKGROUND & AIMS: HBV expresses more than 10 spliced RNAs from the viral pregenomic RNA, but their functions remain elusive and controversial. To address the function of HBV spliced RNAs, we generated splicing-deficient HBV mutants and conducted experiments to assess the impact of these mutants on HBV infection. METHODS: HepG2-NTCP cells, human hepatocyte chimeric FRG mice (hu-FRG mice), and serum from patients with chronic hepatitis B were used for experiments on HBV infection. Additionally, SHifter assays and cryo-electron microscopy were performed. RESULTS: We found the infectivity of splicing-deficient HBV was decreased 100-1,000-fold compared with that of wild-type HBV in hu-FRG mice. Another mutant, A487C, which loses the most abundant spliced RNA (SP1), also exhibits severely impaired infectivity. SP1 hypothetically encodes a novel protein HBcSP1 (HBc-Cys) that lacks the C-terminal cysteine from full-length HBc. In the SHifter assay, HBcSP1 was detected in wild-type viral particles at a ratio of about 20-100% vs. conventional HBc, as well as in the serum of patients with chronic hepatitis B, but not in A487C particles. When infection was conducted with a shorter incubation time of 4-8 h at lower PEG concentrations in HepG2-NTCP cells, the entry of the A487C mutant was significantly slower. SP1 cDNA complementation of the A487C mutant succeeded in rescuing its infectivity in hu-FRG mice and HepG2-NTCP cells. Moreover, cryo-electron microscopy revealed a disulfide bond between HBc cysteine 183 and 48 in the HBc intradimer of the A487C capsid, leading to a locked conformation that disfavored viral entry in contrast to the wild-type capsid. CONCLUSIONS: Prior studies unveiled the potential integration of the HBc-Cys protein into the HBV capsid. We confirmed the proposal and validated its identity and function during infection. IMPACT AND IMPLICATIONS: HBV SP1 RNA encodes a novel HBc protein (HBcSP1) that lacks the C-terminal cysteine from conventional HBc (HBc-Cys). HBcSP1 was detected in cell culture-derived HBV and confirmed in patients with chronic infection by both immunological and chemical modification assays at 10-50% of capsid. The splicing-deficient mutant HBV (A487C) impaired infectivity in human hepatocyte chimeric mice and viral entry in the HepG2-NTCP cell line. Furthermore, these deficiencies of the splicing-deficient mutant could be rescued by complementation with the SP1-encoded protein HBcSP1. We confirmed and validated the identity and function of HBcSP1 during infection, building on the current model of HBV particles.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Humanos , Animais , Vírus da Hepatite B/genética , Camundongos , Células Hep G2 , Hepatite B Crônica/virologia , Splicing de RNA , Mutação , RNA Viral/genética , RNA Viral/metabolismo , Microscopia Crioeletrônica
8.
J Hepatol ; 80(5): 714-729, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38336348

RESUMO

BACKGROUND & AIMS: Mechanisms behind the impaired response of antigen-specific B cells to therapeutic vaccination in chronic hepatitis B virus (HBV) infection remain unclear. The development of vaccines or strategies to overcome this obstacle is vital for advancing the management of chronic hepatitis B. METHODS: A mouse model, denominated as E6F6-B, was engineered to feature a knock-in of a B-cell receptor (BCR) that specifically recognizes HBsAg. This model served as a valuable tool for investigating the temporal and spatial dynamics of humoral responses following therapeutic vaccination under continuous antigen exposure. Using a suite of immunological techniques, we elucidated the differentiation trajectory of HBsAg-specific B cells post-therapeutic vaccination in HBV carrier mice. RESULTS: Utilizing the E6F6-B transfer model, we observed a marked decline in antibody-secreting cells 2 weeks after vaccination. A dysfunctional and atypical pre-plasma cell population (BLIMP-1+ IRF4+ CD40- CD138- BCMA-) emerged, manifested by sustained BCR signaling. By deploying an antibody to purge persistent HBsAg, we effectively prompted the therapeutic vaccine to provoke conventional plasma cell differentiation. This resulted in an enhanced anti-HBs antibody response and facilitated HBsAg clearance. CONCLUSIONS: Sustained high levels of HBsAg limit the ability of therapeutic hepatitis B vaccines to induce the canonical plasma cell differentiation necessary for anti-HBs antibody production. Employing a strategy combining antibodies with vaccines can surmount this altered humoral response associated with atypical pre-plasma cells, leading to improved therapeutic efficacy in HBV carrier mice. IMPACT AND IMPLICATIONS: Therapeutic vaccines aimed at combatting HBV encounter suboptimal humoral responses in clinical settings, and the mechanisms impeding their effectiveness have remained obscure. Our research, utilizing the innovative E6F6-B mouse transfer model, reveals that the persistence of HBsAg can lead to the emergence of an atypical pre-plasma cell population, which proves to be relevant to the potency of therapeutic HBV vaccines. Targeting the aberrant differentiation process of these atypical pre-plasma cells stands out as a critical strategy to amplify the humoral response elicited by HBV therapeutic vaccines in carrier mouse models. This discovery suggests a compelling avenue for further study in the context of human chronic hepatitis B. Encouragingly, our findings indicate that synergistic therapy combining HBV-specific antibodies with vaccines offers a promising approach that could significantly advance the pursuit of a functional cure for HBV.


Assuntos
Hepatite B Crônica , Hepatite B , Camundongos , Humanos , Animais , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Vacinas contra Hepatite B/uso terapêutico , Anticorpos Anti-Hepatite B , Diferenciação Celular , Hepatite B/prevenção & controle , Hepatite B/tratamento farmacológico
9.
J Virol ; 97(2): e0168422, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36651747

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is becoming a dominant circulator and has several mutations in the spike glycoprotein, which may cause shifts of immunogenicity, so as to result in immune escape and breakthrough infection among the already infected or vaccinated populations. It is unclear whether infection with Omicron could generate adequate cross-variant protection. To investigate this possibility, we used Syrian hamsters as an animal model for infection of SARS-CoV-2. The serum from Omicron BA.1 variant-infected hamsters showed a significantly lower neutralization effect against infection of the same or different SARS-CoV-2 variants than the serum from Beta variant-infected hamsters. Furthermore, the serum from Omicron BA.1 variant-infected hamsters were insufficient to protect against rechallenge of SARS-CoV-2 Prototype, Beta and Delta variants and itself. Importantly, we found that rechallenge with different SARS-CoV-2 lineages elevated cross-variant serum neutralization titers. Overall, our findings indicate a weakened immunogenicity feature of Omicron BA.1 variant that can be overcome by rechallenge of a different SARS-CoV-2 lineages. Our results may lead to a new guideline in generation and use of the vaccinations to combat the pandemic of SARS-CoV-2 Omicron variant and possible new variants. IMPORTANCE The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant causes breakthrough infections among convalescent patients and vaccinated populations. However, Omicron does not generate robust cross-protective responses. Here, we investigate whether heterologous SARS-CoV-2 challenge is able to enhance antibody response in a sensitive animal model, namely, Syrian hamster. Of note, a heterologous challenge of Beta and Omicron BA.1 variant significantly broadens the breadth of SARS-CoV-2 neutralizing responses against the prototype, Beta, Delta, and Omicron BA.1 variants. Our findings confirm that vaccination strategy with heterologous antigens might be a good option to protect against the evolving SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Anticorpos Neutralizantes , Anticorpos Antivirais , Antígenos Heterófilos/imunologia , Infecções Irruptivas , COVID-19/prevenção & controle , Mesocricetus , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Imunogenicidade da Vacina
10.
J Virol ; 97(11): e0113723, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37855619

RESUMO

IMPORTANCE: The ongoing COVID-19 pandemic has been characterized by the emergence of new SARS-CoV-2 variants including the highly transmissible Omicron XBB sublineages, which have shown significant resistance to neutralizing antibodies (nAbs). This resistance has led to decreased vaccine effectiveness and therefore result in breakthrough infections and reinfections, which continuously threaten public health. To date, almost all available therapeutic nAbs, including those authorized under Emergency Use Authorization nAbs that were previously clinically useful against early strains, have recently been found to be ineffective against newly emerging variants. In this study, we provide a comprehensive structural basis about how the Class 3 nAbs, including 1G11 in this study and noted LY-CoV1404, are evaded by the newly emerged SARS-CoV-2 variants.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Pandemias , Humanos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais , Infecções Irruptivas , COVID-19/imunologia , COVID-19/virologia
11.
J Virol ; 97(3): e0181922, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36815785

RESUMO

Human papillomaviruses (HPV) are small DNA viruses associated with cervical cancer, warts, and other epithelial tumors. Structural studies have shown that the HPV capsid consists of 360 copies of the major capsid protein, L1, arranged as 72 pentamers in a T=7 icosahedral lattice, coassembling with substoichiometric amounts of the minor capsid protein, L2. However, the residues involved in the coassembly of L1 and L2 remain undefined due to the lack of structure information. Here, we investigated the solvent accessibility surfaces (SASs) of the central cavity residues of the HPV16 L1 pentamer in the crystal structure because those internal exposed residues might mediate the association with L2. Twenty residues in L1 protein were selected to be analyzed, with four residues in the lumen of the L1 pentamer identified as important: F256, R315, Q317, and T340. Mutations to these four residues reduced the PsV (pseudovirus) infection capacity in 293FT cells, and mutations to R315, Q317, and T340 substantially perturb L2 from coassembling into L1 capsid. Compared with wild-type (WT) PsVs, these mutant PsVs also have a reduced ability to become internalized into host cells. Finally, we identified a stretch of negatively charged residues on L2 (amino acids [aa] 337 to 340 [EEIE]), mutations to which completely abrogate L2 assembly into L1 capsid and subsequently impair the endocytosis and infectivity of HPV16 PsVs. These findings shed light on the elusive coassembly between HPV L1 and L2. IMPORTANCE Over 200 types of HPV have been isolated, with several high-risk types correlated with the occurrence of cervical cancer. The HPV major capsid protein, L1, assembles into a T=7 icosahedral viral shell, and associates with the minor capsid protein, L2, which plays a critical role in the HPV life cycle. Despite the important role of the L2 protein, its structure and coassembly with L1 remain elusive. In this study, we analyzed the amino acid residues at the proposed interface between L1 and L2. Certain mutations at these sites decreased the amount of L2 protein assembled into the capsid, which, in turn, led to a decrease in viral infectivity. Knowledge about these residues and the coassembly of L1 and L2 could help to expand our understanding of HPV biology and aid in the development of countermeasures against a wide range of HPV types by targeting the L2 protein.


Assuntos
Proteínas do Capsídeo , Papillomavirus Humano 16 , Feminino , Humanos , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/patogenicidade , Infecções por Papillomavirus/virologia , Sequência de Aminoácidos/genética , Mutação , Linhagem Celular , Estrutura Terciária de Proteína/genética , Modelos Moleculares
12.
Hepatology ; 77(5): 1722-1734, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36106666

RESUMO

BACKGROUND AND AIMS: HEV ORF2 antigen (Ag) in serum has become a tool for diagnosing current HEV infection. Particularly, urinary shedding of HEV Ag has been gaining increasing interest. We aim to uncover the origin, antigenicity, diagnostic performance, and diagnostic significance of Ag in urine in HEV infection. APPROACH AND RESULTS: Clinical serum and urine samples from patients with acute and chronic HEV infection were analyzed for their Ag levels. Ag in urine was analyzed by biochemical and proteomic approaches. The origin of urinary Ag and Ag kinetics during HEV infection was investigated in mouse and rabbit models, respectively. We found that both the Ag level and diagnostic sensitivity in urine were higher than in serum. Antigenic protein in urine was an E2s-like dimer spanning amino acids 453-606. pORF2 entered urine from serum in mice i.v. injected with pORF2. Ag in urine originated from the secreted form of pORF2 (ORF2 S ) that abundantly existed in hepatitis E patients' serum. HEV Ag was specifically taken up by renal cells and was disposed into urine, during which the level of Ag was concentrated >10-fold, resulting in the higher diagnosing sensitivity of urine Ag than serum Ag. Moreover, Ag in urine appeared 6 days earlier, lasted longer than viremia and antigenemia, and showed good concordance with fecal RNA in a rabbit model. CONCLUSIONS: Our findings demonstrated the origin and diagnostic value of urine Ag and provided insights into the disposal of exogenous protein of pathogens by the host kidney.


Assuntos
Vírus da Hepatite E , Hepatite E , Animais , Camundongos , Coelhos , Hepatite E/diagnóstico , Vírus da Hepatite E/genética , Antígenos Virais , Proteômica , Fezes , RNA Viral
13.
J Med Virol ; 96(4): e29568, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38549430

RESUMO

The global incidence rate of kidney cancer (KC) has been steadily increasing over the past 30 years. With the aging global population, kidney cancer has become an escalating concern that necessitates vigilant surveillance. Nowadays, surgical intervention remains the optimal therapeutic approach for kidney cancer, while the availability of efficacious treatments for advanced tumors remains limited. Oncolytic viruses, an emerging form of immunotherapy, have demonstrated encouraging anti-neoplastic properties and are progressively garnering public acceptance. However, research on oncolytic viruses in kidney cancer is relatively limited. Furthermore, given the high complexity and heterogeneity of kidney cancer, it is crucial to identify an optimal oncolytic virus agent that is better suited for its treatment. The present study investigates the oncolytic activity of the Pseudorabies virus live attenuated vaccine (PRV-LAV) against KC. The findings clearly demonstrate that PRV-LAV exhibits robust oncolytic activity targeting KC cell lines. Furthermore, the therapeutic efficacy of PRV-LAV was confirmed in both a subcutaneous tumor-bearing nude mouse model and a syngeneic mouse model of KC. Combined RNA-seq analysis and flow cytometry revealed that PRV-LAV treatment substantially enhances the infiltration of a diverse range of lymphocytes, including T cells, B cells, macrophages, and NK cells. Additionally, PRV-LAV treatment enhances T cell activation and exerts antitumor effects. Importantly, the combination of PRV-LAV with anti-PD-1 antibodies, an approved drug for KC treatment, synergistically enhances the efficacy against KC. Overall, the discovery of PRV-LAV as an effective oncolytic virus holds significant importance for improving the treatment efficacy and survival rates of KC patients.


Assuntos
Vacinas Anticâncer , Herpesvirus Suídeo 1 , Inibidores de Checkpoint Imunológico , Neoplasias Renais , Vírus Oncolíticos , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Herpesvirus Suídeo 1/genética , Neoplasias Renais/terapia , Vírus Oncolíticos/genética , Receptor de Morte Celular Programada 1 , Microambiente Tumoral , Vacinas Atenuadas , Vacinas Anticâncer/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico
14.
Virol J ; 21(1): 245, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369233

RESUMO

BACKGROUND: Cervical squamous cell carcinoma (CSCC) is a prevalent gynecological malignancy worldwide. Current treatments for CSCC can impact fertility and cause long-term complications, underscoring the need for new therapeutic strategies. Oncolytic virotherapy has emerged as a promising option for cancer treatment. Previous research has demonstrated the oncolytic activity of the coxsackievirus B3 strain 2035 A (CVB3/2035A) against various tumor types. This study aims to evaluate the clinical viability of CVB3/2035A for CSCC treatment, focusing on its oncolytic effect in patient-derived CSCC organoids. METHODS: The oncolytic effects of CVB3/2035A were investigated using human CSCC cell lines in vitro and mouse xenograft models in vivo. Preliminary tests for tumor-selectivity were conducted on patient-derived CSCC tissue samples and compared to normal cervical tissues ex vivo. Three patient-derived CSCC organoid lines were developed and treated with CVB3/2035A alone and in combination with paclitaxel. Both cytotoxicity and virus replication were evaluated in vitro. RESULTS: CVB3/2035A exhibited significant cytotoxic effects in human CSCC cell lines and xenograft mouse models. The virus selectively induced oncolysis in patient-derived CSCC tissue samples while sparing normal cervical tissues ex vivo. In patient-derived CSCC organoids, which retained the immunohistological characteristics of the original tumors, CVB3/2035A also demonstrated significant cytotoxic effects and efficient replication, as evidenced by increased viral titers and presence of viral nucleic acids and proteins. Notably, the combination of CVB3/2035A and paclitaxel resulted in enhanced cytotoxicity and viral replication. CONCLUSIONS: CVB3/2035A showed oncolytic activity in CSCC cell lines, xenografts, and patient-derived tissue cultures and organoids. Furthermore, the virus exhibited synergistic anti-tumor effects with paclitaxel against CSCC. These results suggest CVB3/2035A could serve as an alternative or adjunct to current CSCC chemotherapy regimens.


Assuntos
Carcinoma de Células Escamosas , Enterovirus Humano B , Terapia Viral Oncolítica , Vírus Oncolíticos , Organoides , Paclitaxel , Neoplasias do Colo do Útero , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Feminino , Organoides/virologia , Camundongos , Enterovirus Humano B/fisiologia , Enterovirus Humano B/efeitos dos fármacos , Terapia Viral Oncolítica/métodos , Carcinoma de Células Escamosas/virologia , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/tratamento farmacológico , Vírus Oncolíticos/fisiologia , Linhagem Celular Tumoral , Replicação Viral/efeitos dos fármacos
15.
Nature ; 562(7728): 605-609, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30333625

RESUMO

Immune checkpoint blockade therapy has been successful in treating some types of cancer but has not shown clinical benefits for treating leukaemia1. This result suggests that leukaemia uses unique mechanisms to evade this therapy. Certain immune inhibitory receptors that are expressed by normal immune cells are also present on leukaemia cells. Whether these receptors can initiate immune-related primary signalling in tumour cells remains unknown. Here we use mouse models and human cells to show that LILRB4, an immunoreceptor tyrosine-based inhibition motif-containing receptor and a marker of monocytic leukaemia, supports tumour cell infiltration into tissues and suppresses T cell activity via a signalling pathway that involves APOE, LILRB4, SHP-2, uPAR and ARG1 in acute myeloid leukaemia (AML) cells. Deletion of LILRB4 or the use of antibodies to block LILRB4 signalling impeded AML development. Thus, LILRB4 orchestrates tumour invasion pathways in monocytic leukaemia cells by creating an immunosuppressive microenvironment. LILRB4 represents a compelling target for the treatment of monocytic AML.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Evasão Tumoral/imunologia , Animais , Apolipoproteínas E/metabolismo , Arginase/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Movimento Celular , Proliferação de Células , Feminino , Humanos , Tolerância Imunológica/imunologia , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Masculino , Glicoproteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Receptores Imunológicos , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Int J Mol Sci ; 25(18)2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39337359

RESUMO

The Varicella zoster virus (VZV), responsible for both varicella (chickenpox) and herpes zoster (shingles), presents significant global health challenges. While primary VZV infection primarily affects children, leading to chickenpox, reactivation in later life can result in herpes zoster and associated post-herpetic neuralgia, among other complications. Vaccination remains the most effective strategy for VZV prevention, with current vaccines largely based on the attenuated vOka strains. Although these vaccines are generally effective, they can induce varicella-like rashes and have sparked concerns regarding cell virulence. As a safer alternative, subunit vaccines circumvent these issues. In this study, we developed a nanoparticle-based vaccine displaying the glycoprotein E (gE) on ferritin particles using the SpyCatcher/SpyTag system, termed FR-gE. This FR-gE nanoparticle antigen elicited substantial gE-specific binding and VZV-neutralizing antibody responses in BALB/c and C57BL/6 mice-responses that were up to 3.2-fold greater than those elicited by the subunit gE while formulated with FH002C, aluminum hydroxide, or a liposome-based XUA01 adjuvant. Antibody subclass analysis revealed that FR-gE produced comparable levels of IgG1 and significantly higher levels of IgG2a compared to subunit gE, indicating a Th1-biased immune response. Notably, XUA01-adjuvanted FR-gE induced a significant increase in neutralizing antibody response compared to the live attenuated varicella vaccine and recombinant vaccine, Shingrix. Furthermore, ELISPOT assays demonstrated that immunization with FR-gE/XUA01 generated IFN-γ and IL-2 levels comparable to those induced by Shingrix. These findings underscore the potential of FR-gE as a promising immunogen for the development of varicella and herpes zoster vaccines.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Herpesvirus Humano 3 , Nanopartículas , Linfócitos T , Proteínas do Envelope Viral , Animais , Nanopartículas/química , Herpesvirus Humano 3/imunologia , Proteínas do Envelope Viral/imunologia , Anticorpos Neutralizantes/imunologia , Camundongos , Anticorpos Antivirais/imunologia , Linfócitos T/imunologia , Camundongos Endogâmicos BALB C , Feminino , Camundongos Endogâmicos C57BL , Humanos
17.
J Infect Dis ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37738651

RESUMO

BACKGROUND: The value of the widely applied maternal cytomegalovirus (CMV) serological testing approach in predicting intrauterine transmission in highly seroprevalent regions remains unknown. METHODS: A nested case‒control study was conducted based on a maternal-child cohort study. Newborns with congenital CMV (cCMV) infection were included, and each of them was matched to 3 newborns without cCMV infection. Retrospective samples were tested for immunoglobulin G (IgG) avidity and immunoglobulin M (IgM) antibodies in maternal serum and CMV DNA in maternal blood and urine to analyse their associations with cCMV infection. RESULTS: Forty-eight newborns with cCMV infection and 144 matched newborns without infection were included in the study. Maternal IgM antibodies and IgG avidity during pregnancy were not statistically associated with intrauterine transmission. The presence of CMV DNAemia indicated a higher risk of cCMV infection, with the OR values as 5.7, 6.5 and 13.0 in early, middle and late pregnancy, respectively. However, the difference in CMV shedding rates in transmitters and nontransmitters was not significant in urine. CONCLUSION: The value of current maternal CMV serological testing in regions with high seropositivity rates is very limited and should be reconsidered. The detection of DNAemia would be helpful in assessing the risk of intrauterine transmission.

18.
J Infect Dis ; 227(4): 488-497, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35325151

RESUMO

BACKGROUND: Age-specific data on anal, and corresponding cervical, human papillomavirus (HPV) infection are needed to inform female anal cancer prevention. METHODS: We centrally reanalyzed individual-level data from 26 studies reporting HPV prevalence in paired anal and cervical samples by human immunodeficiency virus (HIV) status and age. For women with HIV (WWH) with anal high-grade squamous intraepithelial lesions or worse (HSIL+), we also investigated concurrent cervical cytopathology. RESULTS: In HIV-negative women, HPV16 prevalence decreased significantly with age, both at anus (4.3% at 15-24 years to 1.0% at ≥55 years; ptrend = 0.0026) and cervix (7.4% to 1.7%; ptrend < 0.0001). In WWH, HPV16 prevalence decreased with age at cervix (18.3% to 7.2%; ptrend = 0.0035) but not anus (11.5% to 13.9%; ptrend = 0.5412). Given anal HPV16 positivity, concurrent cervical HPV16 positivity also decreased with age, both in HIV-negative women (ptrend = 0.0005) and WWH (ptrend = 0.0166). Among 48 WWH with HPV16-positive anal HSIL+, 27 (56%) were cervical high-risk HPV-positive, including 8 with cervical HPV16, and 5 were cervical HSIL+. CONCLUSIONS: Age-specific shifts in HPV16 prevalence from cervix to anus suggest that HPV infections in the anus persist longer, or occur later in life, than in the cervix, particularly in WWH. This is an important consideration when assessing the utility of cervical screening results to stratify anal cancer risk.


Assuntos
Neoplasias do Ânus , Infecções por HIV , Infecções por Papillomavirus , Lesões Intraepiteliais Escamosas , Neoplasias do Colo do Útero , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Colo do Útero/patologia , Papillomavirus Humano , Prevalência , Detecção Precoce de Câncer , Neoplasias do Colo do Útero/epidemiologia , Canal Anal , Neoplasias do Ânus/diagnóstico , Papillomavirus Humano 16 , Papillomaviridae/genética , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , HIV , Fatores Etários
19.
Clin Infect Dis ; 76(3): e692-e701, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35869839

RESUMO

BACKGROUND: Understanding the natural history of anal high-risk human papillomavirus (hrHPV) infection is key for designing anal cancer prevention programs but has not been systematically characterized. METHODS: We reanalyzed data from 34 studies including 16 164 individuals in 6 risk groups defined by human immunodeficiency virus (HIV) status, sex, and male sexuality: men who have sex with men (MSM) and people with HIV (MSMWH), HIV-negative MSM, women with HIV (WWH), HIV-negative women, men who have sex with women (MSW) with HIV (MSWWH), and HIV-negative MSW. We used Markov models to estimate incidence and clearance of 13 hrHPV types and their determinants. RESULTS: Human papillomavirus (HPV) 16 had the highest incidence-clearance ratio of the hrHPV types. MSMWH had the highest hrHPV incidence (eg, 15.5% newly HPV-16 infected within 2 years), followed by HIV-negative MSM (7.5%), WWH (6.6%), HIV-negative women (2.9%), MSWWH (1.7%), and HIV-negative MSW (0.7%). Determinants of HPV-16 incidence included HIV status and number of sexual partners for MSM, women, and MSW, and anal sex behavior for MSM only. HPV-16 clearance was lower for people with HIV (PWH) and lower for prevalent than incident infection. Among MSM, increasing age was associated with lower clearance of prevalent, but not incident, HPV-16 infection. CONCLUSIONS: This robust and unifying analysis of anal hrHPV natural history is essential to designing and predicting the impact of HPV vaccination and HPV-based screening programs on anal cancer prevention, particularly in MSM and PWH. Importantly, it demonstrates the higher carcinogenic potential of longstanding anal prevalent hrHPV infection than more recent incident infection.


Assuntos
Doenças do Ânus , Neoplasias do Ânus , Infecções por HIV , Infecções por Papillomavirus , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Homossexualidade Masculina , Papillomavirus Humano , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Incidência , Comportamento Sexual , Canal Anal , Doenças do Ânus/diagnóstico , Estudos Longitudinais , Neoplasias do Ânus/complicações , Papillomavirus Humano 16/genética , HIV , Papillomaviridae/genética
20.
J Clin Microbiol ; 61(12): e0071023, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38038482

RESUMO

The emergence of Rocahepevirus ratti [species HEV ratti (r HEV)] as a causative agent of hepatitis E in humans presents a new potential threat to global public health. The R. ratti genotype 1 (r-1 HEV) variant only shares 50%-60% genomic identity with Paslahepevirus balayani [species HEV balayani (b HEV)] variants, which are the main causes of hepatitis E infection in humans. Here, we report antigen diagnoses for r-1 HEV and b HEV using an enzymatic immunoassay (EIA) method. We detected recombinant virus-like particles protein (HEV 239) of r HEV and b HEV using a collection of hepatitis E virus (HEV)-specific monoclonal antibodies. Two optimal candidates, the capture antibody P#1-H4 and the detection antibodies C145 (P#1-H4*/C145#) and C158 (P#1-H4*/C158#), were selected to detect antigen in infected rat samples and r-1 HEV- or b HEV-infected human clinical samples. The two candidates showed similar diagnostic efficacy to the Wantai HEV antigen kit in b HEV-infected clinical samples. Genomic divergence resulted in low diagnostic efficacy of the Wantai HEV antigen kit (0%, 0 of 10) for detecting r-1 HEV infection. Compared with the P#1-H4*/C145# candidate (80%, 8 of 10), the P#1-H4*/C158# candidate had excellent diagnostic efficacy in r-1 HEV-infected clinical samples (100%, 10 of 10). The two candidates bind to a discrete antigenic site that is highly conserved across r HEV and b HEV. P#1-H4*/C145# and P#1-H4*/C158# are efficacious candidate antibody combinations for rat HEV antigen detection.


Assuntos
Vírus da Hepatite E , Hepatite E , Ratos , Humanos , Animais , Vírus da Hepatite E/genética , Anticorpos Anti-Hepatite , Técnicas Imunoenzimáticas , Testes Imunológicos
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