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Abstract Epstein-Barr virus (EBV) infects more than 95% of adults worldwide and is closely associated with various malignancies. Considering the complex life cycle of EBV, developing vaccines targeting key entry glycoproteins to elicit robust and durable adaptive immune responses may provide better protection. EBV gHgL-, gB- and gp42-specific antibodies in healthy EBV carriers contributed to sera neutralizing abilities in vitro, indicating that they are potential antigen candidates. To enhance the immunogenicity of these antigens, we formulate three nanovaccines by co-delivering molecular adjuvants (CpG and MPLA) and antigens (gHgL, gB or gp42). These nanovaccines induce robust humoral and cellular responses through efficient activation of dendritic cells and germinal center response. Importantly, these nanovaccines generate high levels of neutralizing antibodies recognizing vulnerable sites of all three antigens. IgGs induced by a cocktail vaccine containing three nanovaccines confer superior protection from lethal EBV challenge in female humanized mice compared to IgG elicited by individual NP-gHgL, NP-gB and NP-gp42. Importantly, serum antibodies elicited by cocktail nanovaccine immunization confer durable protection against EBV-associated lymphoma. Overall, the cocktail nanovaccine shows robust immunogenicity and is a promising candidate for further clinical trials.

Epstein–Barr virus (EBV) infection has been related to multiple epithelial cancers and lymphomas. Current efforts in developing a prophylactic EBV vaccine have focused on inducing neutralizing antibodies. However, given the lifelong and persistent nature of EBV infection following primary infection, it is rationalized that an ideal vaccine should elicit both humoral and cellular immune responses targeting multiple stages of the EBV lifecycle. This study used a DNA vector and a TianTan vaccinia virus to express key EBV antigens, including BZLF1, EBNA1, EBNA3B, and gH/gL, to generate multi-antigen vaccines. The multi-antigen vaccine expressing all four antigens and the multi-antigen vaccine expressing BZLF1, EBNA1, and EBNA3B showed comparable protection effects and prevented 100% and 80% of humanized mice, respectively, from EBV-induced fatal B cell lymphoma by activating BZLF1, EBNA1, and EBNA3B specific T cell. The vaccine expressing lytic protein BZLF1 elicited stronger T cell responses and conferred superior protection compared to vaccines targeting single latent EBNA1 or EBNA3B. The vaccine solely expressing gH/gL exhibited no T cell protective effects in our humanized mice model. Our study implicates the potential of EBV vaccines that induce potent cellular responses targeting both latent and lytic phases of the EBV life cycle in the prevention of EBV-induced B cell lymphoma.

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.

ABSTRACTReplicating 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.

Abstract 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.

Abstract 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.

Polygenic Risk Scores (PRS) show promise for facilitating cancer risk stratification. Here, the authors performed a large genome-wide association study and develop a PRS for nasopharyngeal carcinoma, which could improve risk stratification and personalized screening.

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

The glucose transporter GLUT1 is upregulated in multiple cancers and may contribute to tumour progression, but the underlying mechanisms are poorly understood. Here, the authors show that DHHC9-mediated GLUT1 palmitoylation at Cys207 is crucial for plasma membrane localisation of GLUT1 and for tumourigenesis in glioblastoma cells.

Epstein-Barr virus (EBV) is associated with high risk for nasopharyngeal carcinoma (NPC). Here, the authors develop a comprehensive risk score that combines risk effects of EBV and human genetics for NPC risk stratification.

Abstract It remains unknown for decades how some of the therapeutic fusion proteins positive in a small percentage of cancer cells account for patient outcome. Here, we report that osteosarcoma Rab22a-NeoF1 fusion protein, together with its binding partner PYK2, is sorted into exosomes by HSP90 via its KFERQ-like motif (RVLFLN142). The exosomal Rab22a-NeoF1 fusion protein facilitates the pulmonary pre-metastatic niche formation by recruiting bone marrow-derived macrophages. The exosomal PYK2 activates RhoA in its negative recipient osteosarcoma cells and induces signal transducer and activator of transcription 3 activation in its recipient macrophages to increase M2 phenotype. Consequently, lung metastases of its recipient osteosarcoma cells are promoted by this exosomal Rab22a-NeoF1 fusion protein, and this event can be targeted by disrupting its interaction with PYK2 using a designed internalizing RGD peptide.

Nasopharyngeal carcinoma is a diverse cancer characterised by a heterogeneous microenvironment. Here, the authors use single cell sequencing to analyse the tumour microenvironment in 10 nasopharyngeal carcinoma tumours and identify different cell types including immune-suppressive T regulatory, tolerogenic dendritic, and exhausted CD8 T cells.

Epstein-Barr virus (EBV) tegument proteins BBRF2 and BSRF1 have been suggested to form a hetero-complex. Here, He et al. provide the crystal structures of BBRF2 alone and in complex with BSRF1 and suggest that the complex tethers EBV nucleocapsids to the Golgi membrane, facilitating secondary envelopment.

Abstract Metabolic reprogramming plays important roles in development and progression of nasopharyngeal carcinoma (NPC), but the underlying mechanism has not been completely defined. In this work, we found INSL5 was elevated in NPC tumor tissue and the plasma of NPC patients. Plasma INSL5 could serve as a novel diagnostic marker for NPC, especially for serum VCA‐IgA‐negative patients. Moreover, higher plasma INSL5 level was associated with poor disease outcome. Functionally, INSL5 overexpression increased, whereas knockdown of its receptor GPCR142 or inhibition of INSL5 reduced cell proliferation, colony formation, and cell invasion in vitro and tumorigenicity in vivo. Mechanistically, INSL5 enhanced phosphorylation and nuclear translocation of STAT5 and promoted glycolytic gene expression, leading to induced glycolysis in cancer cells. Pharmaceutical inhibition of glycolysis by 2‐DG or blockade of INSL5 by a neutralizing antibody reversed INSL5‐induced proliferation and invasion, indicating that INSL5 can be a potential therapeutic target in NPC. In conclusion, INSL5 enhances NPC progression by regulating cancer cell metabolic reprogramming and is a potential diagnostic and prognostic marker as well as a therapeutic target for NPC.

Osteosarcoma is an aggressive tumour and little is known the mechanisms underpinning its highly metastatic nature. Here, the authors highlight a role for the CK1α/CBX4 axis in driving metastasis, suggesting that this pathway might be targeted for therapeutic benefit.

Objectives: Given the role of exposures related to residence in the development of nasopharyngeal carcinoma (NPC) has not been well explored, present study aims to investigate the magnitude and pattern of associations for NPC with lifelong residential exposures. Materials and Methods: We carried out a multi-center, population-based case-control study with 2533 incident NPC cases and 2597 randomly selected population controls in southern China between 2010 and 2014. We performed multivariate logistic regression to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the risk of NPC associated with residential exposures. Results: Compared with those living in a building over lifetime, risk of NPC was higher for individuals living in a cottage (OR: 1.56; 95% CI: 1.34–1.81) or in a boat (3.87; 2.07–7.21). NPC risk was also increased in individuals using wood (1.34; 1.03–1.75), coal (1.70; 1.17–2.47), or kerosene (3.58; 1.75–7.36) vs. using gas/electricity as cooking fuel; using well water (1.57; 1.34–1.83), river water (1.80; 1.47–2.21), or spring/pond/stream water (2.03; 1.70–2.41) vs. tap water for source of drinking water; living in houses with smaller-sized vs. larger windows in the bedroom (3.08; 2.46–3.86), hall (1.89; 1.55–2.31) or kitchen (1.67; 1.34–2.08); and increasing exposure to cooking smoke [(1.53; 1.20–1.94) for high exposure)] or burned incense [(1.59; 1.31–1.95) for daily use)]. Weighted Cox regression analysis corroborated these results. Conclusion: Poorer residential conditions and household air pollution are associated with an increased risk of NPC. Large-scale studies in other populations or longitudinal studies are warranted to further corroborate these findings.

Abstract Epstein‐Barr virus (EBV) reactivation, reflected by aberrantly increased levels of various serological antibodies, has been suggested to be an early indicator of nasopharyngeal carcinoma (NPC) onset and progression. We have previously suggested that certain lifestyle and dietary factors were associated with elevated serological levels of the antibody against various EBV antigens namely VCA, Zta, EBNA1, and oral EBV DNA loads among healthy population. It remains unclear whether these potential environmental factors would also influence EBV serological antibodies in NPC patients. We conducted an epidemiological study to evaluate the associations between such environmental factors and EBV antibody levels among 1701 NPC patients in South China. Pretreatment serums were collected and examined for VCA‐IgA and EA‐IgA by immunoenzymatic assays and antienzyme rate (AER) of EBV DNase‐specific neutralizing antibody. We found that consumption of Canton‐style herbal tea was significantly correlated with increased serological antibody levels of VCA‐IgA and EA‐IgA, with adjusted ORs of 1.35 (95% CI: 1.03‐1.76) and 1.32 (95% CI: 1.01‐1.73), respectively, in the weekly intake frequency stratum, while not related to AER of EBV DNase‐specific neutralizing antibody. Smoking was found to be not only an apparent risk factor for higher antibody levels of AER in stage III‐IV patients (OR = 1.60, 95% CI: 1.11‐2.30), but also associated closely with NPC stage at diagnosis (OR = 2.17, 95% CI: 1.47‐3.22), with dose‐response effects. In conclusion, we found consumption of Canton‐style herbal tea and cigarette smoking were in positive associations with elevated EBV antibodies in NPC patients, which may be of public health significance for the primary prevention of EBV‐associated diseases especially NPC.

Abstract The aim of this study was to use whole‐exome sequencing to derive a molecular classifier for nasopharyngeal carcinoma (NPC) and evaluate its clinical performance. We performed whole‐exome sequencing on 82 primary NPC tumors from Sun Yat‐sen University Cancer Center (Guangzhou cohort) to obtain somatic single‐nucleotide variants, indels, and copy number variants. A novel molecular classifier was then developed and validated in another NPC cohort (Hong Kong cohort, n = 99). Survival analysis was estimated by the Kaplan‐Meier method and compared using the log‐rank test. Cox proportional hazards model was adopted for univariate and multivariate analyses. We identified three prominent NPC genetic subtypes: RAS/PI3K/AKT (based on RAS, AKT1, and PIK3CA mutations), cell‐cycle (based on CDKN2A/CDKN2B deletions, and CDKN1B and CCND1 amplifications), and unclassified (based on dominant mutations in epigenetic regulators, such as KMT2C/2D, or the Notch signaling pathway, such as NOTCH1/2). These subtypes differed in survival analysis, with good, intermediate, and poor progression‐free survival in the unclassified, cell‐cycle, and RAS/PI3K/AKT subgroups, respectively, among the Guangzhou, Hong Kong, and combined cohorts (n = 82, P = 0.0342; n = 99, P = 0.0372; and n = 181, P = 0.0023; log‐rank test). We have uncovered genetic subtypes of NPC with distinct mutations and/or copy number changes, reflecting discrete paths of NPC tumorigenesis and providing a roadmap for developing new prognostic biomarkers and targeted therapies.

Abstract Whether the association between body size or shape and nasopharyngeal carcinoma (NPC) risk exists or varies by age‐specific body size indicators is unclear. In a population‐based case–control study conducted in Southern China between 2010 and 2014, self‐reported height, weight, and body shape at age 20 and 10 years before interview were collected from 2448 histopathologically confirmed NPC cases and 2534 population‐based controls. Body mass index (BMI) was categorized according to the World Health Organization guidelines for Asian populations: underweight (

Abstract Background The male predominance in the incidence of nasopharyngeal carcinoma (NPC) suggests the contribution of the X chromosome to the susceptibility of NPC. However, no X-linked susceptibility loci have been examined by genome-wide association studies (GWASs) for NPC by far. Methods To understand the contribution of the X chromosome in NPC susceptibility, we conducted an X chromosome-wide association analysis on 1615 NPC patients and 1025 healthy controls of Guangdong Chinese, followed by two validation analyses in Taiwan Chinese (n = 562) and Malaysian Chinese (n = 716). Results Firstly, the proportion of variance of X-linked loci over phenotypic variance was estimated in the discovery samples, which revealed that the phenotypic variance explained by X chromosome polymorphisms was estimated to be 12.63% (non-dosage compensation model) in males, as compared with 0.0001% in females. This suggested that the contribution of X chromosome to the genetic variance of NPC should not be neglected. Secondly, association analysis revealed that rs5927056 in DMD gene achieved X chromosome-wide association significance in the discovery sample (OR = 0.81, 95% CI 0.73–0.89, P = 1.49 × 10−5). Combined analysis revealed rs5927056 for DMD gene with suggestive significance (P = 9.44 × 10−5). Moreover, the female-specific association of rs5933886 in ARHGAP6 gene (OR = 0.62, 95%CI: 0.47–0.81, P = 4.37 × 10−4) was successfully replicated in Taiwan Chinese (P = 1.64 × 10−2). rs5933886 also showed nominally significant gender × SNP interaction in both Guangdong (P = 6.25 × 10−4) and Taiwan datasets (P = 2.99 × 10−2). Conclusion Our finding reveals new susceptibility loci at the X chromosome conferring risk of NPC and supports the value of including the X chromosome in large-scale association studies.

Abstract Our study presents the genetic landscape betel quid chewing‐associated tongue carcinomas (BQ‐TCs). We compared the genetic landscape and mutational signatures of 15 BQ‐TCs, five nonbetel quid chewing‐associated tongue carcinomas (nBQ‐TCs), and 82 tongue carcinomas in general population from the TCGA (TCGA‐TCs) project. The highlights of this research mainly include: (a) The genetic landscape of BQ‐TC was characterized with frequent mutations in RASA1 gene and in CpG islands throughout the genome. (b) The BQ‐TC had a distinct mutational signature from that of nBQ‐TC and tongue carcinomas in the general population, and this signature was associated with the mutations in RASA1 and in CpG islands. (c) Our study indicates that betel quid (BQ) chewing classifies a distinct group of tongue carcinoma. The BQ chewing might not contribute to the tumorigenesis of tongue carcinomas as a mutagen.

Abstract Germline polymorphisms are linked with differential survival outcomes in cancers but are not well studied in nasopharyngeal carcinoma (NPC). Here, a two‐phase association study is conducted to discover germline polymorphisms that are associated with the prognosis of NPC. The discovery phase includes two consecutive hospital cohorts of patients with NPC from Southern China. Exome‐wide genotypes at 246 173 single nucleotide polymorphisms (SNPs) are determined, followed by survival analysis for each SNP under Cox proportional hazard regression model. Candidate SNP is replicated in another two independent cohorts from Southern China and Singapore. Meta‐analysis of all samples (n = 5553) confirms that the presence of rs1131636‐T, located in the 3′‐UTR of RPA1, confers an inferior overall survival (HR = 1.33, 95% CI = 1.20–1.47, P = 6.31 × 10−8). Bioinformatics and biological assays show that rs1131636 has regulatory effects on upstream RPA1. Functional studies further demonstrate that RPA1 promotes the growth, invasion, migration, and radioresistance of NPC cells. Additionally, miR‐1253 is identified as a suppressor for RPA1 expression, likely through regulation of its binding affinity to rs1131636 locus. Collectively, these findings provide a promising biomarker aiding in stratifying patients with poor survival, as well as a potential drug target for NPC.

EBV latent infection contributes to the pathogenesis of epithelial malignancies by inducing angiogenesis. Here, the authors show EBV promotes vasculogenic mimicry in EBV associated epithelial cancers via AKT/HIF-1α pathway and combination therapy of HIF-1α and VEGF reduces tumour growth.

Abstract Background Metastasis is the major cause of treatment failure in patients with nasopharyngeal carcinoma (NPC). We previously reported that TEL2, a negative regulator of SERPINE1, could inhibit NPC metastasis to lymph nodes. Method A series of in vivo and in vitro assays were performed to elucidate the regulation between Snail and TEL2. TEL2 expression was analyzed in three representative NPC cell lines expressing low levels of Snail (S26, 6-10B, HK1) and two cell lines expressing high levels of Snail (S18, 5-8F). Luciferase and chromatin immunoprecipitation assays were used to analyze the interaction between Snail and TEL2. The roles of the Snail/TEL2 pathway in cell migration and invasion of NPC cells were examined using transwell assays. Metastasis to the lungs was examined using nude mouse receiving NPC cells injection through the tail vein. Results Ectopic Snail expression down-regulated TEL2 at the mRNA and protein levels, whereas knockdown of Snail using short hairpin RNA up-regulated TEL2. Luciferase and chromatin immunoprecipitation assays indicated that Snail binds directly to the TEL2 promoter. Ectopic Snail expression enhanced migration and invasion of NPC cells, and such effects were mitigated by TEL2 overexpression. TEL2 overexpression also attenuated hypoxia-induced cell migration and invasion, and increased the number of metastatic pulmonary nodules. Snail overexpression reduced the number of metastatic pulmonary nodules. Conclusions TEL2 is a novel target of Snail and suppresses Snail-induced migration, invasion and metastasis in NPC.

Abstract The link of nasopharyngeal carcinoma (NPC) with Epstein‐Barr virus (EBV) has been established for decades. Although an abnormal high level of EBV sero‐antibody spectrum and cell‐free circulating EBV DNA loads were exhibited in NPC patients, oral EBV DNA loads, which are primarily responsible for the EBV transmission, has not been previously studied in NPC patients. We conducted an epidemiological study to measure the oral EBV loads, viral components, and the relationship with the serum antibody titers in a large case‐control population (968 cases and 1656 controls) and a family‐based population (91 cases and 165 unaffected family members). EBV DNA loads were detected by quantitative PCR approach targeting the BamHI‐W region. Although a large individualized variation existed, we still observed a decreased oral EBV DNA loads in the population of NPC patients compared to that of healthy controls (ORs were 1.00, 0.69, 0.62, 0.33 classified by the quartiles of viral loads, Ptrend

Our previous study found that smoking was associated with an elevated level of the antibody against VCA in the Epstein-Barr virus (EBV) lytic phase, which was an important predictive marker of the risk of nasopharyngeal carcinoma (NPC). It remained unknown whether environmental factors were associated with the levels of other EBV antibodies, such as Zta-IgA, EA-IgA, EBNA1-IgA, and LMP1-IgA, in the lytic and latent infection periods. We aimed to investigate the possible environmental inducers that could affect EBV antibody levels in two independent healthy male populations from endemic NPC areas in South China (N = 1498) and non-endemic NPC areas in North China (N = 1961). We performed ELISA and immunoenzymatic assays to test the levels of antibodies specific to the EBV antigens. The seropositive rates of antibodies against the antigens expressed in both the EBV latent and lytic infection periods, namely, LMP1-IgA, EBNA1-IgA, and Zta-IgA, in endemic areas (28.65%, 5.43% and 14.49%, respectively) were significantly higher than those in non-endemic areas (14.43%, 1.07% and 6.32%, respectively). Smoking was associated with higher seropositivity for EBNA1-IgA (OR = 1.47, 95% CI = 1.12–1.93) and Zta-IgA (OR = 1.28, 95% CI = 0.99–1.66), with dose-response effects, while not associated with the levels of LMP1-IgA. In conclusion, smoking was an important environmental factor, which associated with increased levels of EBNA1-IgA, and Zta-IgA. Keywords: Anti-Epstein-Barr virus antibodies, Asymptomatic males, Cigarette smoking, Nasopharyngeal carcinoma, China

Humanized mouse models are used as comprehensive small-animal models of EBV infection. Previously, infectious doses of EBV used in vivo have been determined mainly on the basis of TD50 (50% transforming dose), which is a time-consuming process. Here, we determined infectious doses of Akata-EBV-GFP using green Raji units (GRUs), and characterized dose-dependent effects in humanized mice. We defined two outcomes in vivo, including an infection model and a lymphoma model, following inoculation with low or high doses of Akata-EBV-GFP, respectively. Inoculation with a low dose induced primary B cells to become lymphoblastoid cell lines in vitro, and caused latent infection in humanized mice. In contrast, a high dose of Akata-EBV-GFP resulted in primary B cells death in vitro, and fatal B cell lymphomas in vivo. Following infection with high doses, the frequency of CD19+ B cells decreased, whereas the percentage of CD8+ T cells increased in peripheral blood and the spleen. At such doses, a small part of activated CD8+ T cells was EBV-specific CD8+ T cells. Thus, GRUs quantitation of Akata-EBV-GFP is an effective way to quantify infectious doses to study pathologies, immune response, and to assess (in vivo) the neutralizing activity of antibodies raised by immunization against EBV.

Neuroblastoma cell differentiation is regulated by Id proteins. Here, the authors show that CaMKII-mediated phosphorylation of Beclin 1 can activate K63-linked ubiquitination and autophagic degradation of Id proteins uncovering a role for autophagy in cell differentiation.