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1.
Cell Genom ; 4(2): 100474, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38359790

RESUMO

Epstein-Barr virus (EBV) and human leukocyte antigen (HLA) polymorphisms are well-known risk factors for nasopharyngeal carcinoma (NPC). However, the combined effects between HLA and EBV on the risk of NPC are unknown. We applied a causal inference framework to disentangle interaction and mediation effects between two host HLA SNPs, rs2860580 and rs2894207, and EBV variant 163364 with a population-based case-control study in NPC-endemic southern China. We discovered the strong interaction effects between the high-risk EBV subtype and both HLA SNPs on NPC risk (rs2860580, relative excess risk due to interaction [RERI] = 4.08, 95% confidence interval [CI] = 2.03-6.14; rs2894207, RERI = 3.37, 95% CI = 1.59-5.15), accounting for the majority of genetic risk effects. These results indicate that HLA genes and the high-risk EBV have joint effects on NPC risk. Prevention strategies targeting the high-risk EBV subtype would largely reduce NPC risk associated with EBV and host genetic susceptibility.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/genética , Neoplasias Nasofaríngeas/epidemiologia , Estudos de Casos e Controles , Polimorfismo de Nucleotídeo Único/genética
3.
J Biol Chem ; 300(3): 105681, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272224

RESUMO

The mechanistic target of rapamycin (mTOR) forms two distinct complexes: rapamycin-sensitive mTOR complex 1 (mTORC1) and rapamycin-insensitive mTORC2. mTORC2 primarily regulates cell survival by phosphorylating Akt, though the upstream regulation of mTORC2 remains less well-defined than that of mTORC1. In this study, we show that NOP14, a 40S ribosome biogenesis factor and a target of the mTORC1-S6K axis, plays an essential role in mTORC2 signaling. Knockdown of NOP14 led to mTORC2 inactivation and Akt destabilization. Conversely, overexpression of NOP14 stimulated mTORC2-Akt activation and enhanced cell proliferation. Fractionation and coimmunoprecipitation assays demonstrated that the mTORC2 complex was recruited to the rough endoplasmic reticulum through association with endoplasmic reticulum-bound ribosomes. In vivo, high levels of NOP14 correlated with poor prognosis in multiple cancer types. Notably, cancer cells with NOP14 high expression exhibit increased sensitivity to mTOR inhibitors, because the feedback activation of the PI3K-PDK1-Akt axis by mTORC1 inhibition was compensated by mTORC2 inhibition partly through NOP14 downregulation. In conclusion, our findings reveal a spatial regulation of mTORC2-Akt signaling and identify ribosome biogenesis as a potential biomarker for assessing rapalog response in cancer therapy.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Sirolimo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Humanos , Linhagem Celular , Ribossomos/metabolismo , Inibidores de Proteínas Quinases/farmacologia
4.
Cell Rep Med ; 4(11): 101296, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37992686

RESUMO

Epstein-Barr virus (EBV) is closely associated with cancer, multiple sclerosis, and post-acute coronavirus disease 2019 (COVID-19) sequelae. There are currently no approved therapeutics or vaccines against EBV. It is noteworthy that combining multiple EBV glycoproteins can elicit potent neutralizing antibodies (nAbs) against viral infection, suggesting possible synergistic effects. Here, we characterize three nAbs (anti-gp42 5E3, anti-gHgL 6H2, and anti-gHgL 10E4) targeting different glycoproteins of the gHgL-gp42 complex. Two antibody cocktails synergistically neutralize infection in B cells (5E3+6H2+10E4) and epithelial cells (6H2+10E4) in vitro. Moreover, 5E3 alone and the 5E3+6H2+10E4 cocktail confer potent in vivo protection against lethal EBV challenge in humanized mice. The cryo-EM structure of a heptatomic gHgL-gp42 immune complex reveals non-overlapping epitopes of 5E3, 6H2, and 10E4 on the gHgL-gp42 complex. Structural and functional analyses highlight different neutralization mechanisms for each of the three nAbs. In summary, our results provide insight for the rational design of therapeutics or vaccines against EBV infection.


Assuntos
Infecções por Vírus Epstein-Barr , Vacinas , Animais , Camundongos , Proteínas do Envelope Viral/química , Glicoproteínas de Membrana , Herpesvirus Humano 4 , Proteínas Virais , Terapia Combinada de Anticorpos , Epitopos , Glicoproteínas , Anticorpos Neutralizantes/uso terapêutico
5.
Cell Host Microbe ; 31(11): 1882-1897.e10, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37848029

RESUMO

Epstein-Barr virus (EBV) is a global public health concern, as it is known to cause multiple diseases while also being etiologically associated with a wide range of epithelial and lymphoid malignancies. Currently, there is no available prophylactic vaccine against EBV. gB is the EBV fusion protein that mediates viral membrane fusion and participates in host recognition, making it critical for EBV infection in both B cells and epithelial cells. Here, we present a gB nanoparticle, gB-I53-50 NP, that displays multiple copies of gB. Compared with the gB trimer, gB-I53-50 NP shows improved structural integrity and stability, as well as enhanced immunogenicity in mice and non-human primate (NHP) preclinical models. Immunization and passive transfer demonstrate a robust and durable protective antibody response that protects humanized mice against lethal EBV challenge. This vaccine candidate demonstrates significant potential in preventing EBV infection, providing a possible platform for developing prophylactic vaccines for EBV.


Assuntos
Infecções por Vírus Epstein-Barr , Vacinas , Cricetinae , Animais , Camundongos , Herpesvirus Humano 4 , Infecções por Vírus Epstein-Barr/prevenção & controle , Formação de Anticorpos , Células CHO , Anticorpos Neutralizantes , Anticorpos Antivirais
6.
Adv Sci (Weinh) ; 10(30): e2301136, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37679058

RESUMO

Doxorubicin-induced cardiomyopathy (DIC) brings tough clinical challenges as well as continued demand in developing agents for adjuvant cardioprotective therapies. Here, a zebrafish phenotypic screening with deep-learning assisted multiplex cardiac functional analysis using motion videos of larval hearts is established. Through training the model on a dataset of 2125 labeled ventricular images, ZVSegNet and HRNet exhibit superior performance over previous methods. As a result of high-content phenotypic screening, cyanidin chloride (CyCl) is identified as a potent suppressor of DIC. CyCl effectively rescues cardiac cell death and improves heart function in both in vitro and in vivo models of Doxorubicin (Dox) exposure. CyCl shows strong inhibitory effects on lipid peroxidation and mitochondrial damage and prevents ferroptosis and apoptosis-related cell death. Molecular docking and thermal shift assay further suggest a direct binding between CyCl and Keap1, which may compete for the Keap1-Nrf2 interaction, promote nuclear accumulation of Nrf2, and subsequentially transactivate Gpx4 and other antioxidant factors. Site-specific mutation of R415A in Keap1 significantly attenuates the protective effects of CyCl against Dox-induced cardiotoxicity. Taken together, the capability of deep-learning-assisted phenotypic screening in identifying promising lead compounds against DIC is exhibited, and new perspectives into drug discovery in the era of artificial intelligence are provided.


Assuntos
Cardiotoxicidade , Aprendizado Profundo , Animais , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Peixe-Zebra/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/farmacologia , Inteligência Artificial , Simulação de Acoplamento Molecular , Estresse Oxidativo , Doxorrubicina/toxicidade
7.
Emerg Microbes Infect ; 12(2): 2245920, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37542379

RESUMO

Epstein-Barr virus (EBV) is the first reported human oncogenic virus and infects more than 95% of the human population worldwide. EBV latent infection in B lymphocytes is essential for viral persistence. Glycoprotein gp42 is an indispensable member of the triggering complex for EBV entry into B cells. The C-type lectin domain (CTLD) of gp42 plays a key role in receptor binding and is the major target of neutralizing antibodies. Here, we isolated two rabbit antibodies, 1A7 and 6G7, targeting gp42 CTLD with potent neutralizing activity against B cell infection. Antibody 6G7 efficiently protects humanized mice from lethal EBV challenge and EBV-induced lymphoma. Neutralizing epitopes targeted by antibodies 1A7 and 6G7 are distinct and novel. Antibody 6G7 blocks gp42 binding to B cell surface and both 1A7 and 6G7 inhibit membrane fusion with B cells. Furthermore, 1A7- and 6G7-like antibodies in immunized sera are major contributors to B cell neutralization. This study demonstrates that anti-gp42 neutralizing antibodies are effective in inhibiting EBV infection and sheds light on the design of gp42-based vaccines and therapeutics.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Coelhos , Humanos , Animais , Camundongos , Herpesvirus Humano 4/metabolismo , Anticorpos Neutralizantes , Glicoproteínas de Membrana/metabolismo , Proteínas Virais/metabolismo , Epitopos
8.
Exp Biol Med (Maywood) ; 248(12): 1085-1094, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37208923

RESUMO

Cytoskeleton-associated protein 4 (CKAP4) acts as a key transmembrane protein that connects the endoplasmic reticulum (ER) to microtubule dynamics. Researchers have not examined the roles of CKAP4 in nasopharyngeal carcinoma (NPC). The study aimed at evaluating the prognostic value and metastasis-regulating effect of CKAP4 in NPC. CKAP4 protein could be observed in 86.36% of 557 NPC specimens but not in normal nasopharyngeal epithelial tissue. According to immunoblot assays, NPC cell lines presented high CKAP4 expression relative to NP69 immortalized nasopharyngeal epithelial cells. Moreover, CKAP4 was highly expressed at the NPC tumor front and in matched liver, lung, and lymph node metastasis samples. Furthermore, high CKAP4 expression reported poor overall survival (OS) and presented a positive relevance to tumor (T) classification, recurrence, and metastasis. According to multivariate analysis, CKAP4 could independently and negatively predict patients' prognosis. Stable knockdown of CKAP4 expression in NPC cells inhibited cell migration, invasion and metastasis in vitro and in vivo. Moreover, CKAP4 promoted epithelial-mesenchymal transition (EMT) in NPC cells. CKAP4 knockdown was followed by the downregulation of the interstitial marker vimentin, and upregulation of the epithelial marker E-cadherin. In NPC tissues, high CKAP4 expression exhibited a positive relevance to vimentin expression and a negative relevance to E-cadherin expression. In conclusion, CKAP4 is an independent predictor of NPC, and CKAP4 might contribute NPC progression and metastasis, which may be involved in EMT with vimentin and E-cadherin.


Assuntos
Neoplasias Nasofaríngeas , Humanos , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Citoesqueleto/metabolismo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/patologia , Invasividade Neoplásica/genética , Vimentina
10.
Trends Microbiol ; 31(8): 788-804, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36967248

RESUMO

Herpesviruses are among the most successful viruses found in human populations. They establish lifelong latent infections, which are punctuated by recurrent reactivations. The entry process of herpesviruses into specific target cells requires a well-orchestrated teamwork involving multiple envelope glycoproteins. The conserved glycoprotein B (gB) is the membrane fusogen, of which conformational changes are induced by an entry complex (EC) consisting of at least gH and gL. Despite the high prevalence and heavy disease burdens associated with human herpesviruses (HHVs), vaccines against these pathogens are still lacking, except for varicella zoster virus (VZV). Recent advances in understanding the coordinated mechanisms of action of the key EC glycoproteins and fusogen will help to improve approaches for effective vaccine development and neutralizing antibody (nAb) screening.


Assuntos
Herpesviridae , Proteínas do Envelope Viral , Humanos , Glicoproteínas , Anticorpos Neutralizantes/uso terapêutico , Internalização do Vírus
11.
Can J Gastroenterol Hepatol ; 2023: 8370262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937571

RESUMO

Purpose: The purpose of the current study was to determine whether there is a difference between high levels of microsatellite instability (MSI-H) and microsatellite stability (MSS) in DNA mismatch repair-deficient (DMMR) colorectal cancer (CRC) patients. Methods: A total of 452 CRC patients with DMMR from December, 2014, to April, 2021, in our hospital were selected retrospectively. However, only 105 patients underwent Sanger or next-generation-sequencing (NGS) to confirm their microsatellite status. Ultimately, 55 MSI-H patients and 20 MSS patients with intact medical record information were included in this study. Results: The MSS group was associated with a higher mutation rate in the KRAS gene (P=0.011). Meanwhile, MSI-H was related to colon cancer (P < 0.01). However, no significant differences in other clinical characteristics were observed between the two groups of patients. There was no significant difference between the MSI-H and MSS groups in terms of overall survival (OS) (P=0.398) and disease-free survival (DFS) (P=0.307). Conclusion: The MSI-H status was associated with colon cancer and a lower mutation rate of the KRAS gene in DMMR patients. In CRC-DMMR patients, the MSS group exhibited better OS and DFS than the MSI-H group, although these differences were not statistically significant. Accordingly, in clinical practice, we should not confuse these two types of patients.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Instabilidade de Microssatélites , Reparo de Erro de Pareamento de DNA/genética , Prognóstico , Estudos Retrospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias do Colo/genética , Neoplasias Colorretais/genética , Repetições de Microssatélites
12.
Int J Cancer ; 153(2): 290-301, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-36965052

RESUMO

A concern of reverse causation exists about the association between nasopharyngeal carcinoma (NPC) prognosis and body mass index (BMI) at diagnosis, while the prognostic impact of BMI measured years before diagnosis is unknown. Therefore, we investigated associations of prediagnosis and pretreatment BMI and body shape on NPC mortality. From a population-based patient cohort in southern China between 2010 and 2013, we included 2526 incident NPC cases with prospective follow-up through 2018. We assessed the associations of BMI and body shape at age 20 years, 10 years before diagnosis, and at diagnosis with NPC mortality, combining strategies of stratification and statistical adjustment to minimize reverse causation. We observed 25% lower all-cause mortality (hazard ratio [HR] 0.75, 95% confidence interval [CI]: 0.64-0.89) and 25% lower NPC-specific mortality (HR 0.75, 95% CI: 0.61-0.91) among overweight vs normal-weight NPC cases at diagnosis. Lean body shapes 1 and 2 at diagnosis were associated with 68% and 23% higher all-cause mortality, respectively, compared to normal body shape 3. No effect modification by cancer stage was detected for associations with all-cause or NPC-specific mortality. Associations with BMI and body shape 10 years before diagnosis were similar but attenuated, while body size and shape at age 20 were not associated with mortality. Being overweight at diagnosis decreased mortality, and thinner body shape increased mortality, compared to normal weight/body shape. These associations may be due to poorer nutrition and treatment intolerance, resulting in treatment discontinuation and worse survival outcomes.


Assuntos
Neoplasias Nasofaríngeas , Sobrepeso , Humanos , Adulto Jovem , Adulto , Carcinoma Nasofaríngeo , Índice de Massa Corporal , Sobrepeso/complicações , Somatotipos , Estudos Prospectivos , Prognóstico , Neoplasias Nasofaríngeas/diagnóstico , China/epidemiologia , Fatores de Risco
13.
Emerg Microbes Infect ; 12(1): 2185467, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36849422

RESUMO

Replicating SARS-CoV-2 has been shown to degrade HLA class I on target cells to evade the cytotoxic T-cell (CTL) response. HLA-I downregulation can be sensed by NK cells to unleash killer cell immunoglobulin-like receptor (KIR)-mediated self-inhibition by the cognate HLA-I ligands. Here, we investigated the impact of HLA and KIR genotypes and HLA-KIR combinations on COVID-19 outcome. We found that the peptide affinities of HLA alleles were not correlated with COVID-19 severity. The predicted poor binders for SARS-CoV-2 peptides belong to HLA-B subtypes that encode KIR ligands, including Bw4 and C1 (introduced by B*46:01), which have a small F pocket and cannot accommodate SARS-CoV-2 CTL epitopes. However, HLA-Bw4 weak binders were beneficial for COVID-19 outcome, and individuals lacking the HLA-Bw4 motif were at higher risk for serious illness from COVID-19. The presence of the HLA-Bw4 and KIR3DL1 combination had a 58.8% lower risk of developing severe COVID-19 (OR = 0.412, 95% CI = 0.187-0.904, p = 0.02). This suggests that HLA-Bw4 alleles that impair their ability to load SARS-CoV-2 peptides will become targets for NK-mediated destruction. Thus, we proposed that the synergistic responsiveness of CTLs and NK cells can efficiently control SARS-CoV-2 infection and replication, and NK-cell-mediated anti-SARS-CoV-2 immune responses being mostly involved in severe infection when the level of ORF8 is high enough to degrade HLA-I. The HLA-Bw4/KIR3DL1 genotype may be particularly important for East Asians undergoing COVID-19 who are enriched in HLA-Bw4-inhibitory KIR interactions and carry a high frequency of HLA-Bw4 alleles that bind poorly to coronavirus peptides.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Antígenos HLA-B/genética , Células Matadoras Naturais , Receptores KIR3DL1/genética
15.
Cancer Med ; 12(7): 9055-9067, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36708053

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is an aggressive heterogeneous hematological malignancy with remarkably heterogeneous outcomes. This study aimed to identify potential biomarkers for AML risk stratification via analysis of gene expression profiles. METHODS: RNA sequencing data from 167 adult AML patients in the Cancer Genome Atlas (TCGA) database were obtained for overall survival (OS) analysis, and 52 bone marrow (BM) samples from our clinical center were used for validation. Additionally, siRNA was used to investigate the role of prognostic genes in the apoptosis and proliferation of AML cells. RESULTS: Co-expression of 103 long non-coding RNAs (lncRNAs) and mRNAs in the red module that were positively correlated with European Leukemia Network (ELN) risk stratification and age was identified by weighted gene co-expression network analysis (WGCNA). After screening by uni- and multivariate Cox regression, Kaplan-Meier survival, and protein-protein interaction analysis, four genes including the lncRNA LOC541471, GDAP1, SOD1, and STK25 were incorporated into calculating a risk score from coefficients of the multivariate Cox regression model. Notably, GDAP1 expression was the greatest contributor to OS among the four genes. Interestingly, the risk score, ELN risk stratification, and age were independent prognostic factors for AML patients, and a nomogram model constructed with these factors could illustrate and personalize the 1-, 3-, and 5-year OS rates of AML patients. The calibration and time-dependent receiver operating characteristic curves (ROCs) suggested that the nomogram had a good predictive performance. Furthermore, new risk stratification was developed for AML patients based on the nomogram model. Importantly, knockdown of LOC541471, GDPA1, SOD1, or STK25 promoted apoptosis and inhibited the proliferation of THP-1 cells compared to controls. CONCLUSIONS: High expression of LOC541471, GDAP1, SOD1, and STK25 may be biomarkers for risk stratification of AML patients, which may provide novel insight into evaluating prognosis, monitoring progression, and designing combinational targeted therapies.


Assuntos
Leucemia Mieloide Aguda , RNA Longo não Codificante , Adulto , Humanos , Superóxido Dismutase-1 , Biomarcadores Tumorais/metabolismo , Leucemia Mieloide Aguda/patologia , Prognóstico , Perfilação da Expressão Gênica , RNA Longo não Codificante/metabolismo , Proteínas Serina-Treonina Quinases/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética
16.
Front Psychiatry ; 13: 1005062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465300

RESUMO

Objective: According to the General Strain Theory, stress can lead to a range of problem behaviors. In the current study, we focused on the association between perceived stress and mobile phone addiction. We hypothesized that this association is mediated by low self-control and that the first path of the mediation is moderated by security. Methods: College students (N = 397; ages 16-21; 51.89% females) from a university in Hunan Province, China, were surveyed by cluster sampling method. The students completed the Smartphone Addiction Scale-Short Version (SAS-SV), the Depression Anxiety Stress Scale (DASS-21), the Self-Control Scale (SCS), and the Security Questionnaire (SQ) during regular class time. SPSS26.0 statistical software was used for descriptive statistics and Pearson correlation analyses, the SPSS macro PROCESS was used to test the mediating effects of self-control and the moderating role of security. Results: Mediation analysis showed that as expected, perceived stress was associated with lower self-control, which in turn was associated with a higher risk for mobile phone addiction. Also as expected, moderated mediation analysis indicated that the association between perceived stress and self-control was moderated by security. Specifically, the relationship between perceived stress and self-control was stronger for low security. Conclusion: This study provides useful insight into the understanding of how perceived stress increases the risk of mobile phone addiction. The results are consistent with the General Strain Theory and further indicate that concrete approaches are required for the prevention and intervention to reduce mobile phone addiction among college students.

17.
NPJ Vaccines ; 7(1): 159, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494369

RESUMO

Epstein-Barr virus (EBV), a γ-herpesvirus, is the first identified oncogenic virus, which establishes permanent infection in humans. EBV causes infectious mononucleosis and is also tightly linked to many malignant diseases. Various vaccine formulations underwent testing in different animals or in humans. However, none of them was able to prevent EBV infection and no vaccine has been approved to date. Current efforts focus on antigen selection, combination, and design to improve the efficacy of vaccines. EBV glycoproteins such as gH/gL, gp42, and gB show excellent immunogenicity in preclinical studies compared to the previously favored gp350 antigen. Combinations of multiple EBV proteins in various vaccine designs become more attractive approaches considering the complex life cycle and complicated infection mechanisms of EBV. Besides, rationally designed vaccines such as virus-like particles (VLPs) and protein scaffold-based vaccines elicited more potent immune responses than soluble antigens. In addition, humanized mice, rabbits, as well as nonhuman primates that can be infected by EBV significantly aid vaccine development. Innovative vaccine design approaches, including polymer-based nanoparticles, the development of effective adjuvants, and antibody-guided vaccine design, will further enhance the immunogenicity of vaccine candidates. In this review, we will summarize (i) the disease burden caused by EBV and the necessity of developing an EBV vaccine; (ii) previous EBV vaccine studies and available animal models; (iii) future trends of EBV vaccines, including activation of cellular immune responses, novel immunogen design, heterologous prime-boost approach, induction of mucosal immunity, application of nanoparticle delivery system, and modern adjuvant development.

18.
Virol J ; 19(1): 196, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36424667

RESUMO

BACKGROUND: Epstein-Barr virus (EBV) is a wide-spread human herpesvirus that is highly associated with infectious mononucleosis and several malignancies. Evaluation of EBV neutralizing antibody titers is important for serological studies, vaccine development and monoclonal antibody screening. The traditional method based on antibody inhibition of EBV transformation of B cells is very time-consuming. A more practical flow cytometry-based (FCM) approach to evaluate neutralizing titers is not amenable to achieving high-throughput evaluation of large-scale samples. A high-throughput approach is urgently needed. RESULTS: Here, we present a rapid and high-throughput method based on high content imaging system (HCIS) analysis. EBV titers determined by the HCIS-based assay were similar to those obtained by the FCM-based assay. Neutralizing titers of sera and monoclonal antibodies measured by the HCIS-based assay strongly correlated with titers measured by the FCM-based assay. HCIS assays showed a strong correlation between B cell infection neutralizing titers and the anti-gp350 IgG titers in healthy EBV carriers and monkey sera. Finally, anti-gHgL IgG titers from sera of healthy EBV carriers significantly correlated with epithelial cell infection neutralizing titers. CONCLUSIONS: This HCIS-based assay is a high-throughput assay to determine viral titers and evaluate neutralizing potentials of sera and monoclonal antibodies. This HCIS-based assay will aid the development of vaccines and therapeutic monoclonal antibody against EBV.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Humanos , Anticorpos Antivirais , Imunoglobulina G , Anticorpos Monoclonais
19.
Psychiatr Danub ; 34(3): 475-482, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36256985

RESUMO

BACKGROUND: Mobile phone addiction among adolescents has attracted a lot of attention in recent years. Previous researches revealed a significant relation between low social support and addiction. This study aim to investigated the association between social support and mobile phone addiction, and the mediating effects of depression and loneliness. SUBJECTS AND METHODS: A total of 1,400 Chinese adolescents aged from 12 to 23 years old was recruited from two middle schools and a college in Hunan Province, China. Participates were selected using the cluster random sampling method. They completed the Mobile Phone Addiction Index, the Self-Rating Depression Scale, the UCLA Loneliness Scale, and the Adolescent Social Support Scale. The study analyzed the correlations between the study variables and the mediating role of depression and loneliness in the relationship between social support and mobile phone addiction. RESULTS: There were significant negative correlation between social support and depression, loneliness, and mobile phone addiction (p<0.001). Both depression and loneliness demonstrated significant positive correlation with mobile phone addiction (p<0.001). Structural equation modeling revealed that both depression and loneliness mediated the association between social support and mobile phone addiction (p<0.001). Depression and loneliness sequentially mediated the association between social support and mobile phone addiction (p<0.001). However, the relation between social support and mobile phone addiction was not significant (p>0.05). CONCLUSIONS: Social support can lower levels of mobile phone addiction among adolescents by reducing depression and loneliness. This study sheds light on the underlying mechanisms between social support and mobile phone addiction, which has profound implications for the prevention and interventions of adolescent problematic mobile phone use.


Assuntos
Telefone Celular , Solidão , Adolescente , Humanos , Criança , Adulto Jovem , Adulto , Depressão/epidemiologia , Inquéritos e Questionários , Apoio Social
20.
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
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