N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer

BACKGROUND N6-methyladenosine(m6A)methylation modification exists in Epstein-Barr virus(EBV)primary infection,latency,and lytic reactivation.It also modifies EBV latent genes and lytic genes.EBV-associated gastric cancer(EBVaGC)is a distinctive molecular subtype of GC.We hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of GC.AIM To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of GC.METHODS First,The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC(EBVnGC).Second,we identified Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment of m6A-related differentially expressed genes.We quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment(TME).Finally,cell counting kit-8 cell proliferation test,transwell test,and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1(IGFBP1)in EBVaGC cell lines.RESULTS m6A methylation regulators were involved in the occurrence and development of EBVaGC.Compared with EBVnGC,the expression levels of m6A methylation regulators Wilms tumor 1-associated protein,RNA binding motif protein 15B,CBL proto-oncogene like 1,leucine rich pentatricopeptide repeat containing,heterogeneous nuclear ribonucleoprotein A2B1,IGFBP1,and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC(P<0.05).The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher(P=0.046).GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in EBVaGC.Compared with EBVnGC,the infiltration of activated CD4+T cells,activated CD8+T cells,monocytes,activated dendritic cells,and plasmacytoid dendritic cells were significantly upregulated in EBVaGC(P<0.001).In EBVaGC,the expression level of proinflammatory factors interleukin(IL)-17,IL-21,and interferon-γ and immunosuppressive factor IL-10 were significantly increased(P<0.05).In vitro experiments demonstrated that the expression level of IGFBP1 was significantly lower in an EBVaGC cell line(SNU719)than in an EBVnGC cell line(AGS)(P<0.05).IGFBP1 overexpression significantly attenuated proliferation and migration and promoted the apoptosis levels in SNU719.Interfering IGFBP1 significantly promoted proliferation and migration and attenuated the apoptosis levels in AGS.CONCLUSION m6A regulators could remodel the TME of EBVaGC,which is classified as an immune-inflamed phenotype and referred to as a“hot”tumor.Among these regulators,we demonstrated that IGFBP1 affected proliferation,migration,and apoptosis.

Evaluating the role of interleukin-2 and interleukin-12 in pediatric patients with concurrent Mycoplasma pneumoniae and Epstein-Barr virus infections

BACKGROUND Mycoplasma pneumoniae(MP)frequently causes respiratory infections in children,whereas Epstein-Barr virus(EBV)typically presents subclinical manifestations in immunocompetent pediatric populations.The incidence of MP and EBV coinfections is often overlooked clinically,with the contributory role of EBV in pulmonary infections alongside MP remaining unclear.AIM To evaluate the serum concentrations of interleukin-2(IL-2)and interleukin-12(IL-12)in pediatric patients with MP pneumonia co-infected with EBV and assess their prognostic implications.METHODS We retrospectively analyzed clinical data from patients diagnosed with MP and EBV co-infection,isolated MP infection,and a control group of healthy children,spanning from January 1,2018 to December 31,2021.Serum IL-2 and IL-12 levels were quantified using enzyme-linked immunosorbent assay.Logistic regression was employed to identify factors influencing poor prognosis,while receiver operating characteristic(ROC)curves evaluated the prognostic utility of serum IL-2 and IL-12 levels in co-infected patients.RESULTS The co-infection group exhibited elevated serum IL-2 and C-reactive protein(CRP)levels compared to both the MP-only and control groups,with a reverse trend observed for IL-12(P<0.05).In the poor prognosis cohort,elevated CRP and IL-2 levels,alongside prolonged fever duration,contrasted with reduced IL-12 levels(P<0.05).Logistic regression identified elevated IL-2 as an independent risk factor and high IL-12 as a protective factor for adverse outcomes(P<0.05).ROC analysis indicated that the area under the curves for IL-2,IL-12,and their combination in predicting poor prognosis were 0.815,0.895,and 0.915,respectively.CONCLUSION Elevated serum IL-2 and diminished IL-12 levels in pediatric patients with MP and EBV co-infection correlate with poorer prognosis,with combined IL-2 and IL-12 levels offering enhanced predictive accuracy.

Research Advances in Infectious Mononucleosis Caused by Epstein-Barr Virus

Infectious mononucleosis (IM), primarily caused by the Epstein-Barr virus (EBV), manifests as the classic triad of fever, pharyngitis, and cervical lymphadenopathy. Severe cases may involve organ damage, most commonly affecting the liver. Diagnosis relies on a combination of clinical presentation and laboratory parameters, with commonly used indicators including EBV-specific antibodies, EBV-DNA load, and the ratio of atypical lymphocytes. Treatment primarily involves symptomatic supportive care, with a cautious approach to the routine use of antiviral medications. In recent years, significant research in traditional Chinese medicine has been conducted in China, showing promising advancements. This article provides a comprehensive review of EBV-induced infectious mononucleosis, offering insights for clinical diagnosis and treatment.

Positive correlation between latent Epstein-Barr virus infection and severity of illness in inflammatory bowel disease patients

BACKGROUND Emerging studies indicate the critical involvement of microorganisms,such as Epstein-Barr virus(EBV),in the pathogenesis of inflammatory bowel disease(IBD).Immunosuppressive therapies for IBD can reactivate latent EBV,complicating the clinical course of IBD.Moreover,the clinical significance of EBV expression in B lymphocytes derived from IBD patients’intestinal tissues has not been explored in detail.AIM To explore the clinical significance of latent EBV infection in IBD patients.METHODS Latent EBV infection was determined by double staining for EBV encoded RNA and CD20 in colon specimens of 43 IBD patients who underwent bowel resection.Based on the staining results,the patients were divided into two groups,according to their latent EBV infection states-negative(n=33)and positive(n=10).Illness severity of IBD were assigned according to Crohn’s disease activity index(ulcerative colitis)and Mayo staging system(Crohn’s disease).The clinicpathological data were analyzed between the two different latent EBV groups and also between the mild-to-moderate and severe disease groups.RESULTS Systolic pressure(P=0.005),variety of disease(P=0.005),the severity of illness(P=0.002),and pre-op corticosteroids(P=0.025)were significantly different between the EBV-negative and EBV-positive groups.Systolic pressure(P=0.001),variety of disease(P=0.000),pre-op corticosteroids(P=0.011)and EBV infection(P=0.003)were significantly different between the mild-to-moderate and severe disease groups.CONCLUSION IBD patients with latent EBV infection may manifest more severe illnesses.It is suggested that the role of EBV in IBD development should be further investigated,latent EBV infection in patients with serious IBD should be closely monitored,and therapeutic course should be optimized.

Epstein-Barr virus-induced infection-associated hemophagocytic lymphohistiocytosis with acute liver injury:A case report

BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a severe hyperinflammatory reaction,which is rare and life-threatening.According to the pathogen,HLH is divided into genetic and acquired.The most common form of acquired HLH is infection-associated HLH,of which Herpes viruses,particularly Epstein-Barr virus(EBV),are the leading infectious triggers.However,it is difficult to distinguish between simple infection with EBV and EBV-induced infectionassociated HLH since both can destroy the whole-body system,particularly the liver,thereby increasing the difficulty of diagnosis and treatment.CASE SUMMARY This paper elaborates a case about EBV-induced infection-associated HLH and acute liver injury,aiming to propose clinical guides for the early detection and treatment of patients with EBV-induced infection-associated HLH.The patient was categorized as acquired hemophagocytic syndrome in adults.After the ganciclovir antiviral treatment combined with meropenem antibacterial therapy and methylprednisolone inhibition to inflammatory response,gamma globulin enhanced immunotherapy,the patient recovered.CONCLUSION From the diagnosis and treatment of this patient,attention should be paid to routine EBV detection and a further comprehensive understanding of the disease as well as early recognition and early initiation are keys to patients’survival.

Epstein-Barr virus:Silent companion or causative agent of chronic liver disease?

The Epstein-Barr virus(EBV)has an important and multifaceted role in liver pathology.As a member of the herpes virus family,EBV establishes a persistent infection in more than 90%of adults.Besides acute hepatitis during primary infection,many clinical syndromes of interest for the hepatologist are associated with EBV infection.The role of EBV in the evolution of chronic hepatitis from hepatotropic viruses is considered.Chronic EBVassociated hepatitis is suspected in immunocompetent adults with compatible serology,suggestive histology and detection of the viral genome in the liver and/or increase of specific circulating cytotoxic T-lymphocytes.EBV is the main cause of post-transplant lymphoproliferative disorders which occur in up to 30%of cases.EBV-driven lymphoproliferative diseases are also recognized in non-immunocompromised patients and liver is involved in up to a third of the cases.Directly implicated in the pathogenesis of different tumors,EBV has a disputable role in hepatocellular carcinoma carcinogenesis.Further research is required in order to establish or reject the role of EBV in human liver cancer.This paper attempts to discuss the range of EBV-associated chronic liver diseases in immunocompetent patients,from mild,self-limiting mononuclear hepatitis to liver cancer.

Clinical and pathological characterization of epstein-barr virus-associated gastric carcinomas in portugal

AIM To determine the prevalence of epstein-barr virus(eb V)-associated gastric carcinomas in the North Region of Portugal and to study its clinicopathological characteristics. METHODS We have performed a retrospective study including a total of 179 consecutive patients with gastric cancer(GC) submitted to gastrectomy during 2011 at the Portuguese Oncology Institute of Porto. Clinical and pathological data was collected from individual clinical records and inserted on a database with unique codification. Tumour tissues were collected from the institutional tumour bank. eb V was detected by in situ hybridization for the detection of eb V-encoded small RNAs(ebe Rs) and eb V latent proteins(LMP1 and LMP2 A) were detected by immunohistochemistry.RESULTS The analysis showed that eb V-associated gastric carcinomas(eb Va GC) represents 8.4%(15/179) of all GC cases, with a significant differential distribution among histological types(P < 0.001): 100%(3/3) of medullary carcinomas, 100%(1/1) of adenosquamous carcinoma, 8.7%(8/92) of tubular adenocarcinomas, 8.0%(2/25) of mixed carcinomas and 2%(1/51) in poorly cohesive carcinomas. The analysis revealed a higher predominance of eb Va GC in the upper third and middle(cardia, fundus and body) of the stomach(P = 0.041), a significant lower number of regional lymph nodes invasion(P = 0.025) and a tendency for better prognosis(P = 0.222). eb V latent protein expression revealed that all eb Va GC cases were LMP1-negative, nevertheless 6 cases(40%) expressed LPM2 A, which reveals that these cases show a distinct eb V-Latency profile(latency II-like).CONCLUSION eb Va GC represents 8.4% of all GC in the North Region of Portugal. The eb V-infected patients have specific clinic-pathological features that should be further explored to develop new strategies of management and treatment.

Development of Epstein-Barr virus-associated gastric cancer:Infection,inflammation,and oncogenesis

Epstein-Barr virus(EBV)-associated gastric cancer(EBVaGC)cells originate from a single-cell clone infected with EBV.However,more than 95%of patients with gastric cancer have a history of Helicobacter pylori(H.pylori)infection,and H.pylori is a major causative agent of gastric cancer.Therefore,it has long been argued that H.pylori infection may affect the development of EBVaGC,a subtype of gastric cancer.Atrophic gastrointestinal inflammation,a symptom of H.pylori infection,is observed in the gastric mucosa of EBVaGC.Therefore,it remains unclear whether H.pylori infection is a cofactor for gastric carcinogenesis caused by EBV infection or whether H.pylori and EBV infections act independently on gastric cancer formation.It has been reported that EBV infection assists in the oncogenesis of gastric cancer caused by H.pylori infection.In contrast,several studies have reported that H.pylori infection accelerates tumorigenesis initiated by EBV infection.By reviewing both clinical epidemiological and experimental data,we reorganized the role of H.pylori and EBV infections in gastric cancer formation.

Epstein-Barr virus-associated smooth muscle tumors in immunocompromised patients:Six case reports

BACKGROUND Epstein-Barr virus associated smooth muscle tumor(EBV-SMT)is a rare oncological entity.However,there is an increasing incidence of EBV-SMTs,as the frequency of organ transplantation and immunosuppression grows.EBV-SMT diagnosis relies on histopathology and immunochemical staining to distinguish it from post-transplant lymphoproliferative disorder(PTLD).There is no clear consensus on the treatment of EBV-SMTs.However,surgical resection,chemotherapy,radiation therapy,and immunosuppression reduction have been explored with varying degrees of success.CASE SUMMARY Our case series includes six cases of EBV-SMTs across different age groups,with different treatment modalities,adding to the limited existing literature on this rare tumor.The median latency time between immunosuppression and disease diagnosis is four years.EBV-SMTs present with variable degrees of aggressiveness and seem to have worse clinical outcomes in patients with tumor multiplicity and worse immunocompetency.CONCLUSION It is imperative to continue building on this knowledge and keeping EBV-SMTs on the differential in immunocompromised individuals.

Heterochronic triple primary malignancies with Epstein-Barr virus infection and tumor protein 53 gene mutation:A case report and review of literature

BACKGROUND The diagnosis and etiology of multiple primary malignant neoplasms(MPMNs)are difficult to establish.Here,we report a case of heterochronic triple primary malignancies with gastric cancer,nasopharyngeal squamous cell cancer,and then rectal cancer.CASE SUMMARY The patient was first diagnosed with gastric cancer at the age of 33 in 2014 and underwent distal gastrectomy and gastrojejunostomy and six cycles of adjuvant chemotherapy.Three years later,he was diagnosed with nasopharyngeal cancer and treated with radical chemoradiotherapy in 2017.Recently,a mass in the middle of the rectum was resected and reported as ulcerative,moderately to poorly differentiated adenocarcinoma.Research on the etiology of MPMNs showed that Epstein-Barr virus(EBV)infection may be the cause of gastric cancer and nasopharyngeal squamous cell cancer since these two primary lesions were positive for transcripts of EBV-encoded ribonucleic acid using an in situ hybridization EBV-encoded ribonucleic acid probe in formalin-fixed,paraffinembedded tissue.The cause of rectal cancer may be due to a somatic mutation of tumor protein 53 gene in exon 8(c.844C>T,p.Arg282Trp)through highthroughput sequencing for the rectal cancer.Appropriate standard therapy for each primary cancer was administered,and the patient has no evidence of cancer disease to date.CONCLUSION To our knowledge,this is the first report on heterochronic triple primary malignancies whose cause may be associated with EBV infection and tumor protein 53 genetic mutations.The etiological research may not only elucidate the cause of MPMN but also has implications in clinical management.

Epstein-Barr virus-encoded small RNAs in idiopathic orbital inflammatory pseudotumor tissues: a comparative case series

AIM： To investigate the positive rate and types of cells that express Epstein-Barr virus-encoded small RNAs （EBERs） and to determine the distribution of EBER-expressing cells in idiopathic orbital inflammatory pseudotumor （IOIP） tissues. METHODS： We retrospectively examined 40 archived paraffin specimens from two teaching hospitals in Southern China between January 2007 and January 2015 that were pathologically determined to exhibit IOIP. Eleven concurrent paraffin specimens of thyroid-associated ophthalmopathy （TAO） composed the control group. In situ hybridization was performed to detect EBERs. Immunohistochemistry was employed to detect CD3, CD20, Vimentin, and smooth muscle actin （SMA）, and the positive rate, types of positive cells, and distribution and location of EBERs were evaluated. RESULTS： The positive expression rate of EBERs was 47.5% （19/40） in the IOIP group, which was significantly higher than that in the TAO group [0 （0/11）, P=-0.011]. in the IOIP group, the lymphocyte infiltrative subtype, fibrotic subtype, and mixed subtype exhibited EBER-positive rates of 57.1% （12121）, 12.5% （118）, and 54.5% （6/11）, respectively, and no significant differences were found between these subtypes （P=0.085）. Positive signals of EBERs were mainly present in medium-small lymphocytes between or around follicles and in the nuclei of activated immunoblasts （14/19）. CONCLUSION： The positive rate, types, and distribution of EBER-expressing cells in IOIP have been documented.These findings are conducive for a better understanding of the underlying mechanisms of Epstein-Barr virus infection in IOIP pathogenesis.

Epstein-Barr Virus EA-IgA, VCA-IgA, and EBVNA-IgG Antibodies in a Population of Wuhan, China

The study investigated the distribution of Epstein-Barr virus(EBV)EA-IgA,VCAIgA,and EBVNA-IgG antibodies in a local population of Wuhan,China.Chemiluminescence immunoassay(CL1A)was used to detect EBV EA-IgA,VCA-IgA,and EBVNA-IgG antibodies in 972 subjects undergoing physical examination in Wuhan,and the results were analyzed.The detection rate of EBV was positively correlated with age.In the 972 cases,there was significant difference between different genders in the positive rate of VCA-IgA and EBVNA-IgG.Moreover,the positive rate of VCA-IgA and EBVNA-IgG was higher in men>60 years old than in those<60 but no significant differences were found in three antibodies among various age groups.Our results suggested that the EBV infection should be intensively monitored in elderly people in Wuhan.

Screening of Epstein-Barr Virus Early Antigen Expression Inducers from Chinese Medicinal Herbs and Plants

Ether extrilcls of 1693 Chinesc medicinal herbs and plilnts from 268 families werestudied for the induction of Epstcin-Barr viral (EBV ) early antigcn (EA ) expression in theRaji cell line. Fifty-two from 18 families were found to have inducing activity. Twenty-fiveand seven of them were from Euphorbiaccae and Thymclaeaceae, respectively. Some ofthem, such as Croton tiglium, Euphorbia kansui, Daphnc genkwa, Wikstrocmia chamacdaphen, Wikstroemia indica, Prunus mandshurica Koehne and Achyranthes bidentata arecommonly used drugs. The significance of these herbs in the activation of EBV in vivo andtheir relation to the development of nasopharyngeal carcinoma were discussed.

Chronic active Epstein-Barr virus infection treated with PEGaspargase: A case report

BACKGROUND Chronic active Epstein-Barr virus infection(EBV)is a systemic EBV-positive lymphoproliferative disease,which may lead to fatal illness.There is currently no standard treatment regimen for chronic active EBV(CAEBV),and hematopoietic stem cell transplantation is the only effective treatment.We here report a CAEBV patient treated with PEG-aspargase,who achieved negative EBV-DNA.CASE SUMMARY A 33-year-old female Chinese patient who had fever for approximately 3 mo was admitted to our hospital in December 2017.EBV-DNA was positive with a high copy number.She was diagnosed with chronic active EB virus infection.PEGaspargase was administered at a dose of 1500 U/m2 at a 14-d interval,resulting in eradication of EBV for more than 6 mo.The effect of PEG-aspargase in this patient was excellent.CONCLUSION A chemotherapy regimen containing PEG-aspargase for CAEBV may be further considered.

Epstein-Barr virus-positive post-transplant lymphoproliferative disordepresenting as hematochezia and enterobrosis in renal transplant recipients in China: A report of two cases

BACKGROUND Post-transplant lymphoproliferative disorder(PTLD) is a rare severe complication after renal transplantation, with an incidence of approximately 0.3%-2.0% in patients undergoing renal transplantation. The clinical manifestations of PTLD are often nonspecific, leading to tremendous challenges in the clinical diagnosis and treatment of PTLD.CASE SUMMARY We report two Epstein-Barr virus(EBV)-positive PTLD cases whose main clinical manifestations were digestive tract symptoms. Both of them admitted to our hospital because of extranodal infiltration symptoms and we did not suspect of PTLD until the pathology confirmation. Luckily, they responded well to the treatment of rituximab. We also discuss the virological monitoring, clinical characteristics, diagnosis, and treatment of PTLD.CONCLUSION PTLD is a deceptive disease and difficult to diagnose. Once patients are confirmed with PTLD, immune suppressant dosage should be immediately reduced and rituximab should be used as first-line therapy.

Differential DNA methylation profiles of human B lymphocytes and Epstein-Barr virus-immortalized B lymphocytes

Objective： This study aimed to comprehensively assess Epstein-Barr virus（EBV）-induced methylation alterations of B cell across whole genome.Methods： We compared DNA methylation patterns of primary B cells and corresponding lymphoblastoid cell lines（LCLs） from eight participants. The genome-wide DNA methylation profiles were compared at over 850,000 genome-wide methylation sites.Results： DNA methylation analysis revealed 87,732 differentially methylated Cp G sites, representing approximately 12.41% of all sites in LCLs compared to primary B cells. The hypermethylated and hypomethylated Cp G sites were about 22.75% or 77.25%, respectively. Only 0.8% of hypomethylated sites and 4.5% of hypermethylated sites were located in Cp G islands, whereas 8.0% of hypomethylated sites and 16.3% of hypermethylated sites were located in shore（N_shore and S_shore）. Using principal component analysis of the DNA methylation profiles, primary B cells and LCLs could be accurately predicted. Gene Ontology（GO） and Kyoto Encyclopedia of Genes and Genomes（KEGG） analysis of differently methylated genes revealed that most of the top GO biological processes were related to cell activation and immune response, and some top enrichment pathways were related with activation and malignant transformation of human B cells.Conclusions： Our study demonstrated genome-wide DNA methylation variations between primary B cells and corresponding LCLs, which might yield new insight on the methylation mechanism of EBV-induced immortalization.

A Rare Case of Non-small Cell Lung Carcinoma Squamous Phenotype with Epstein-Barr Virus Positivity with Prolonged Response to both Chemotherapy and Radiotherapy

We present a rare challenging case of metastatic non-small cell lung cancer with Epstein-Barr virus positivity that was also diagnosed with pulmonary tuberculosis at the same time. Palliative chemotherapy gemcitabine and carboplatin was started after two weeks of anti-tuberculosis treatment with the hopes that this period would be sufficient to keep acid fast bacilli non-viable to minimise risk of tuberculosis re-activation due to chemotherapy induced immunosuppression. She completed four cycles of chemotherapy and six months of anti-tuberculosis treatment with good results and minimal side effects. Two years later, there was disease recurrence in cervical and mediastinal lymph nodes which was treated with local treatment i.e. surgery and palliative radiotherapy. It has been two years since last radiotherapy and overall more than five years since diagnosis with no active disease at present. Given the complexity and rarity of this case, significant multidisciplinary team involvement, including oncologists and radiation oncologists, pulmonologists with special interest in tuberculosis and pathologists was necessary throughout.

Epstein-Barr virus DNA loads in the peripheral blood cells predict the survival of locoregionally-advanced nasopharyngeal carcinoma patients

Objective:Circulating cell-free Epstein-Barr virus(EBV)DNA has been shown to be a valuable biomarker for population screening and prognostic surveillance for nasopharyngeal carcinoma(NPC).Despite important insights into the biology of persistence,few studies have addressed the clinical significance of cell-based EBV-DNA loads in peripheral blood cells(PBCs).Methods:A prospective observational cohort study was conducted involving 1,063 newly diagnosed,locoregionally-advanced NPC patients at Sun Yat-sen University Cancer Center from 2005 to 2007.Cox regression analysis was conducted to identify the association of PBC EBV DNA loads to overall survival(OS)and other prognostic outcomes.Prognostic nomograms were developed based on PBC EBV DNA loads to predict survival outcomes for NPC patients.Results:After a median follow-up of 108 months,patients with higher PBC EBV-DNA loads had significantly worse OS[hazard ratio(HR)of medium,medium-high,and high vs.low were 1.50,1.52,and 1.85 respectively;Ptrend<0.001].Similar results were found for progression-free survival and distant metastasis-free survival.The concordance index of the prognostic nomogram for predicting OS in the training set and validation set were 0.70 and 0.66,respectively.Our data showed that the PBC EBV DNA load was an independent and robust survival biomarker,which remained significant even after adjusting for plasma EBV DNA loads in a subset of 205 patients of the cohort(HR:1.88;P=0.025).Importantly,a combination of PBC EBV DNA load and plasma EBV DNA load improved the predicted OS.Conclusions:The EBV-DNA load in PBCs may be an independent prognosis marker for NPC patients.

The Viral Load of Epstein-Barr Virus in Blood of Children after Hematopoietic Stem Cell Transplantation

Objective To detect the Epstein-Barr virus(EBV)viral load of children after hematopoietic stem cell transplantation(HSCT)using chip digital PCR(cdPCR).Methods The sensitivity of cdPCR was determined using EBV plasmids and the EBV B95-8 strain.The specificity of EBV cdPCR was evaluated using the EBV B95-8 strain and other herpesviruses(herpes simplex virus 1,herpes simplex virus 2,varicella zoster virus,human cytomegalovirus,human herpesvirus 6,and human herpesvirus 7).From May 2019 to September 2020,64 serum samples of children following HSCT were collected.EBV infection and the viral load of serum samples were detected by cdPCR.The epidemiological characteristics of EBV infections were analyzed in HSCT patients.Results The limit of detection of EBV cdPCR was 110 copies/mL,and the limit of detection of EBV quantitative PCR was 327 copies/mL for the pUC57-BALF5 plasmid.The result of EBV cdPCR was up to 121 copies/mL in the EBV B95-8 strain,and both were more sensitive than that of quantitative PCR.Using cdPCR,the incidence of EBV infection was 18.75%in 64 children after HSCT.The minimum EBV viral load was 140 copies/mL,and the maximum viral load was 3,209 copies/mL using cdPCR.The average hospital stay of children with EBV infection(184±91 days)was longer than that of children without EBV infection(125±79 days),P=0.026.Conclusion EBV cdPCR had good sensitivity and specificity.The incidence of EBV infection was 18.75%in 64 children after HSCT from May 2019 to September 2020.EBV cdPCR could therefore be a novel method to detect EBV viral load in children after HSCT.

STRUCTURE AND EXPRESSION OF EPSTEIN-BARR VIRUS MEMBRANE ANTIGEN IN RECOMBINANT VACCINIA VIRUS

The Epstein-Barr virus membrane antigen was constructed and inserted into vaccinia virus, Tian-tan strain in order to study the effect of this virus on EB infection and tumorogenesis. The EBV-derived membrane antigen was expressed under the control of a 7.5 K promoter of vaccinia virus. The antibody against the membrane antigen of EB virus was produced on rabbits vaccinated with recombinant vaccinia virus.