Chronic Active Epstein-Barr Virus Infection Research Articles

LYMPHOCYTES IN PATIENTS WITH CHRONIC ACTIVE EPSTEIN-BARR VIRUS INFECTION EXHIBITED ELEVATED PD-1/PD-L1 EXPRESSION AND A PREVAILING TH2 IMMUNE RESPONSE.

Background And Objectives: Chronic active Epstein-Barr virus infection (CAEBV) is a lymphoproliferative disorder characterized by the increased numbers of EBV-infected T/natural killer (NK) cells and ongoing symptoms resembling infectious mononucleosis. Nonetheless, the exact correlation between peripheral lymphocyte subsets and the development of CAEBV remains uncertain. Methods: Consequently, we examined the levels of programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) expression, the status of EBV infection, and the frequencies of peripheral lymphocyte subpopulations in 24 patients with CAEBV and 15 EBV-seronegative donors using flow cytometry. Results: Patients with CAEBV showed a notable rise in the expression levels of PD-1 and PD-L1 in peripheral T and NK cells compared to healthy donors (P < 0.05). The induction of PD-L1 expression was attributed to EBV infection. Moreover, most of the T cells infected with EBV displayed a memory phenotype characterized by the presence of CD45RO+. Additionally, patients with CAEBV showed markedly decreased frequency of helper T cells 1 (Th1) and naïve T (Tn) cells, and significantly elevated frequency of Th2 and effector-memory T (Tem) cells. Conclusions: To summarize, EBV might evade the immune system by inducing PD-1/PD-L1 expression in peripheral T and NK cells, and promoting Th2 immune response dominance. Additionally, it may establish long-term persistence by infecting memory T cells in CAEBV.

Novel plasma microRNA expression features in diagnostic use for Epstein-Barr virus-associated febrile diseases

BackgroundEpstein-Barr virus (EBV) is widely infected in humans and causes various diseases. Among them, microRNAs of EBV play a key role in the progression of EBV-associated febrile diseases. There're few specific indicators for rapid differential diagnosis of various febrile diseases associated with EBV, and the lack of more reliable screening methods with high diagnostic utility has led to spaces for improvement in the accurate diagnosis and efficient treatment of relevant patients, making EBV infection a complicated clinical problem. With recent advances in plasma microRNA testing, the apparent presence of EBV microRNAs in plasma can help screen for EBV infection. The gene networks targeted by these microRNAs can also indicate potential biomarkers of EBV-associated febrile diseases. This study aimed to identify some novel miRNAs as potential biomarkers for early diagnosis of respectively EBV-associated febrile diseases. Materials and methodsA total of 110 participants were recruited for this task. First, we performed high-throughput sequencing and preliminary PCR validation of differentially expressed miRNAs in 15 participants with EBV-associated fever (divided into 5 groups, common EBV carriers, infectious mononucleosis (IM) and chronic active EBV infection (CAEBV), EBV-associated Hemophagocytic Lymphohistiocytosis (EBV-HLH), and 3 healthy individuals). After a comprehensive analysis, 10 miRNAs with abnormal expression were screened, and then qRT-PCR was performed in the rest of 95 participants to detect the validation of miRNAs expression in plasma samples. Thereafter, we further investigated their potential for clinical application in EBV-related febrile diseases by using a combination of Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and Protein-protein interaction network analysis. ResultsThrough identification and detailed analysis of the obtained data, we found significant differences in the expression of Hsa-miR-320d, EBV-miR-BART22, and EBV-miR-BART2-3p in blood samples from patients with different EBV-related febrile diseases. We found that the expression levels of Hsa-miR-320d, EBV-miR-BART22, and EBV-miR-BART2-3p in plasma are indicative of determining different disease types of EBV-related febrile diseases, while EBV-miR-BART22 and EBV-miR-BART2-3p may be potential therapeutic targets. ConclusionThe expression levels of Hsa-miR-320d, EBV-miR-BART22, and EBV-miR-BART2-3p suggest that they may be used as transcriptional features for early differential diagnosis of EBV-related febrile diseases, and EBV-miR-BART22 and EBV-miR-BART2-3p may be potential therapeutic targets.

Ultra-low doses of microARNs restore a strong immune response in patients with Chronic Active Epstein-Barr Virus infection (CAEBV)

Chronic active Epstein-Barr Virus infection (CAEBV) is an abnormal response of the immune system to EBV infection, characterized by the absence of anti-EBNA (EBV Nuclear Antigens) IgG and associated with chronic fatigue and several immune related diseases. We present here an innovative therapeutic approach of CAEBV based on the use of ultra-low doses of non-coding RNAs (ncRNAs) involved in the host-virus interaction. We performed a retrospective study on 26 patients treated with our remedy. All the patients expect one developed positive EBNA IgG within eighteen months of starting treatment. Among the 25 cases that seroconverted, 75% report a significant improvement of their symptoms, especial of chronic fatigue. This study gives the proof of the efficiency of ultra-low doses of ncRNAs in restoring a strong immune response against EBV. More generally, this therapeutic approach can potentially be used in almost all pathologies.

Differentiating Between Epstein-Barr Virus-positive Lymphoid Neoplasm Relapse and Post-transplant Lymphoproliferative Disorder After Sex-mismatched Hematopoietic Stem Cell Transplantation.

After allogeneic hematopoietic stem cell transplantation (HSCT), accurate differentiation between donor-derived post-transplant lymphoproliferative disorder (PTLD) and relapse of recipient-derived lymphoproliferative disorder (LPD) is crucial for determining treatment. Conventional diagnostic approaches for PTLD include histopathological examination, flow cytometry, and chimerism analysis of bulk tumor tissue. However, these methods are inconclusive in cases in which the primary disease is an Epstein-Barr virus (EBV)-positive LPD and is of the same lineage as that of the post-HSCT LPD tumor cells. Particularly, in cases where the number of tumor cells in the tissue is low, it is difficult to determine the origin of tumor cells. In this study, we developed a new method to simultaneously detect signals using sex chromosome fluorescence in situ hybridization, immunofluorescence staining, and EBV-encoded small RNA in situ hybridization on a single section of formalin-fixed paraffin-embedded histopathological specimen. The utility of the method was validated using specimens from 6 cases of EBV-positive LPD after sex-mismatched HSCT that were previously difficult to diagnose, including Hodgkin lymphoma-like PTLD that developed after HSCT for Hodgkin lymphoma and recurrence of chronic active EBV infection. This method successfully preserved the histologic structure after staining and allowed accurate determination of tumor cell origin and lineage at the single-cell level, providing a definitive diagnosis in all cases. This method provides a powerful tool for the diagnosis of LPDs after sex-mismatched HSCT.

Haploidentical Transplantation with Post-Transplant Cyclophosphamide Versus Single Cord Blood Transplantation for Adults with Relapsed/Refractory Malignant Lymphoma

Introduction Although the treatment of malignant lymphoma has diversified with the advent of chimeric antigen receptor T-cell therapy and other novel agents, allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a curative treatment for some patients with relapsed/refractory malignant lymphoma (R/R ML). R/R ML eligible for allo-HSCT often requires urgent transplantation, making human leukocyte antigen (HLA)-haploidentical transplantation with post-transplant cyclophosphamide (PTCY-haplo) or cord blood transplantation (CBT) a promising option when HLA-matched donors are unavailable. PTCY-haplo has recently been reported to achieve similar or better clinical outcomes than CBT for other hematological malignancies, though data regarding R/R ML are insufficient. Therefore, this study compares PTCY-haplo and CBT for patients with R/R ML using the Transplant Registry Unified Management Program 2 (TRUMP2) in Japan. Methods This study included adult patients with R/R ML registered with TRUMP2 who underwent PTCY-haplo and CBT for their first allo-HSCT between January 2013 and December 2021. In this study, R/R ML included mature B-, T-, and NK-cell neoplasms, as defined in the World Health Organization's 2017 classification. Patients undergoing allo-HSCT for Hodgkin's lymphoma, aggressive NK-cell leukemia, chronic active Epstein-Barr virus (EBV) infection, systemic EBV-positive T-cell lymphoma of childhood, or adult T-cell leukemia/lymphoma were excluded. The primary endpoint was 3-year overall survival (OS). A Cox proportional hazard regression model for OS was used to estimate hazard ratios (HR) with 95% confidence intervals (CI) in the multivariate analysis. The following factors were included in the multivariate model: donor type, age, sex, performance status, Hematopoietic Cell Transplantation-specific Comorbidity Index score, disease status at allo-HSCT, conditioning regimen, cytomegalovirus seropositivity, and disease linage. The secondary endpoints were 3-year progression-free survival (PFS), 3-year graft versus host disease (GVHD)/relapse-free survival (GRFS), 3-year cumulative incidence of relapse and non-relapse mortality (NRM), 28-day cumulative incidence of neutrophil engraftment, 100-day cumulative incidence of platelet engraftment, 100-day cumulative incidence of grade II-IV and grade III-IV acute GVHD, and 3-year cumulative incidence of any and extensive chronic GVHD. Results A total of 1093 patients, including 223 who underwent PTCY-haplo and 870 who underwent CBT, were included in the study. The median age was 54 years (interquartile range, 44-61 years), and 616 (56%) patients had B-cell lymphoma. The PTCY-haplo group included older patients, more patients who were positive for cytomegalovirus antibodies in recipients or donors, and more patients who received a reduced-intensity conditioning regimen. The 3-year OS was 49% (95% CI: 41-56%) in the PTCY-haplo group and 42% (95% CI: 38-45%) in the CBT group (P=0.090). The adjusted HR was 0.88 (95% CI: 0.70-1.09, P=0.20). The PTCY-haplo group had comparable 3-year PFS, 3-year GRFS, 3-year relapse rates, and 3-year NRM as the CBT group. The PTCY-haplo group had higher neutrophil engraftment at 28 days (92.8% [95%CI: 88.5-95.6%] vs 81.6% [95%CI: 78.9-84.0%], P<0.001) and platelet engraftment at 100 days (77.6% [95%CI: 71.5-82.5%] vs 71.0% [95%CI: 67.9-73.9%], P<0.001); similar grade II-IV acute GVHD at 100 days and 3-year cumulative incidences of chronic GVHD and extensive chronic GVHD; and lower grade III-IV acute GVHD at 100 days (7.17% [95%CI: 4.27-11.1%] vs 13.6% [95%CI 11.5-16.0], P=0.01). Conclusion In this population, PTCY-haplo and CBT result in similar 3-year OS after allo-HSCT. Faster engraftment and less severe acute GVHD were noted in the PTCY-haplo group.

Chronic active Epstein-Barr virus infection mimicking tuberculosis - A diagnostic enigma.

Chronic active EBV infection is a rare disorder prone for misdiagnosis. They present with a wide range of symptoms from indolent to aggressive clinical course. Clinico-pathological correlation with confirmation by ancillary techniques is inevitable to diagnose this disease. We present a case of a 29-year-old male with fever, weight loss, and lymphadenopathy for 6 months. Lymph node biopsy showed occasional granuloma with preserved architecture. Suspected to have tuberculosis, he received antitubercular treatment (ATT) with no response for 3 months. Subsequently, additional workup showed many EBV-positive cells in sinusoids with high serum EBV titer, confirming the difficult diagnosis of CAEBV. The present case highlights the difficulty in the diagnosis of this entity and also emphasizes the necessity to recognize this disorder in countries endemic for tuberculosis, as it is no longer bound by ethnicity and geographical boundaries.

Clinical characteristics of peripheral lymphocyte subtypes in chronic active Epstein-Barr virus infection.

To analyze the clinical characteristics of peripheral Epstein-Barr virus(EBV)-infected lymphocyte subtypes in children with chronic active EBV infection(CAEBV). The levels of peripheral EBV infection of CD4 + T cells, CD8 + T cells, and CD56 + NK cells were determined by flow cytometry and qPCR in patients with CAEBV from July 2017 to July 2022. A total of 112 children with CAEBV were evaluated in the study. Of them, CD4 + type, CD8 + type, and CD56 + type were defined in 44, 21, and 47 patients, respectively. Patients with CD8 + T-cell type had a significantly higher frequency of rash, while hepatomegaly was more common in patients with CD4 + T-cell type. Generally, patients with CD8 + T-cell type had the lowest overall survival(OS) rate(P = 0.017). As for treatment, patients treated with chemotherapy and hematopoietic stem cell transplantation had a better prognosis(P = 0.001). In multivariate analysis, rash, HLH, CD8 + T-cell type, and no decrease of plasma EBV-DNA after treatment were indicated as independent factors of poor prognosis(P = 0.002, 0.024, 0.022, and 0.012, respectively). In children with CAEBV, the rash was more frequent in patients with CD8 + T-cell type, whereas patients with CD4 + T-cell type were more likely to develop hepatomegaly. Patients with CD8 + T-cell type had a poor prognosis despite receiving chemotherapy or further HSCT.

Sintilimab treatment for chronic active Epstein–Barr virus infection and Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis in children

BackgroundChronic active Epstein–Barr virus infection (CAEBV) and Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) are rare but life-threatening progressive diseases triggered by EBV infection. Glucocorticoid/immunosuppressants treatment is temporarily effective; however, most patients relapse and/or progress. Hematopoietic stem cell transplantation (HSCT) is a potentially curative therapy; however, there are risks of transplantation-associated complications. Currently there is no standard treatment for CAEBV and EBV-HLH. Programmed death protein 1 (PD-1) inhibitors have achieved a high response in many EBV-related diseases. Sintilimab (a recombinant human IgG4 monoclonal antibody against PD-1) disrupts the interaction between PD-1 and its ligand, leading to T cell reinvigoration.MethodsA retrospective analysis was performed on three children with CAEBV or EBV-HLH in the Children’s Hospital of Soochow University between 12 December 2020 and 28 November 2022. The efficacy of sintilimab was evaluated.ResultsThree patients, including two males and one female, were analyzed. Among them, two children were diagnosed with CAEBV with intermittent fever for more than four years, and one child was diagnosed with EBV-HLH. After sintilimab treatment and a mean follow-up of 17.1 months (range 10.0–23.3 months), patients 1 and 3 achieved a complete clinical response and patient 2 achieved a partial clinical response. All three children showed a > 50% decrease in EBV-DNA load in both blood and plasma. EBV-DNA copies in sorted T, B, and NK cells were also markedly decreased after sintilimab treatment.ConclusionOur data supported the efficacy of PD-1 targeted therapy in certain patients with CAEBV and EBV-HLH, and suggested that sintilimab could provide a cure for these diseases, without HSCT. More prospective studies and longer follow-up are needed to confirm these conclusions.

Updated guidelines for chronic active Epstein-Barr virus disease.

Chronic active Epstein-Barr virus disease (CAEBV), formerly named chronic active Epstein-Barr virus infection, is characterized by systemic inflammation and clonal proliferation of Epstein-Barr virus (EBV)-infected T or NK cells. As CAEBV is a potentially life-threatening illness, appropriate diagnosis and therapeutic interventions are necessary for favorable clinical outcomes. Substantial evidence regarding the pathogenesis and treatment of CAEBV has been accumulated since previous guidelines for the diagnosis of CAEBV were proposed. To reflect this evidence, we updated the guidelines for the diagnosis and treatment of CAEBV to improve clinical management of the disease. The details of the updated guidelines are presented in this report. Diagnosis of CAEBV now requires confirmation of a high copy number of EBV genome and EBV-infected T or NK cells. An EBV DNA load ≥ 10,000IU/mL in whole blood is proposed as the diagnostic cutoff value for CAEBV in this updated guideline. A standard treatment approach for CAEBV has not been established, and hematopoietic stem cell transplantation (HSCT) is considered the only curative treatment. Chemotherapy can be administered to control disease activity before HSCT.

T cell-mediated immunity during Epstein-Barr virus infections in children.

Epstein-Barr virus (EBV) infection is extremely common worldwide, with approximately 90% of adults testing positive for EBV antibodies. Human are susceptible to EBV infection, and primary EBV infection typically occurs early in life. EBV infection can cause infectious mononucleosis (IM) as well as some severe non-neoplastic diseases, such as chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), which can have a heavy disease burden. After primary EBV infection, individuals develop robust EBV-specific T cell immune responses, with EBV-specific CD8+ and part of CD4+ T cells functioning as cytotoxic T cells, defending against virus. Different proteins expressed during EBV's lytic replication and latent proliferation can cause varying degrees of cellular immune responses. Strong T cell immunity plays a key role in controlling infection by decreasing viral load and eliminating infected cells. However, the virus persists as latent infection in EBV healthy carriers even with robust T cell immune response. When reactivated, it undergoes lytic replication and then transmits virions to a new host. Currently, the relationship between the pathogenesis of lymphoproliferative diseases and the adaptive immune system is still not fully clarified and needs to be explored in the future. Investigating the T cell immune responses evoked by EBV and utilizing this knowledge to design promising prophylactic vaccines are urgent issues for future research due to the importance of T cell immunity.

Bioinformatics analysis to screen the key genes in pediatric Chronic Active Epstein-Barr Virus Infection.

Chronic active EBV infection (CAEBV) is associated with poor prognosis and high mortality. We performed bioinformatics analysis to screen out key genes associated with CAEBV. Weighted gene co-expression network analysis (WGCNA) was used to identify the gene module which was most correlated with pediatric CAEBV. Furthermore, the differentially expressed genes (DEGs) between pediatric acute infectious mononucleosis (AIM) and pediatric CAEBV were investigated. Least absolute shrinkage and selection operator (LASSO) and random forest then were performed to identify the key variables associated with pediatric CAEBV. We also explored the correlation between these hub genes with EBV infection related pathway and immune cell abundance. Compared with pediatric AIM, 1561 DEGs were up-regulated in pediatric CAEBV, and these genes were mainly enriched in inflammatory response and inflammation-related pathways. WGCNA analysis showed that genes in blue module were mostly related to pediatric CAEBV. Genes in the blue module and DEGs are intersected to get 174 genes and these genes are also enriched in inflammatory response-related pathways. The key CAEBV-related genes were selected from these 174 genes by applying the random Forest and LASSO algorithm, resulting in TPST1, TNFSF8 and RAB3GAP1. These three genes showed good diagnostic performance in distinguishing pediatric CAEBV from pediatric AIM. Furthermore, Cibersort and GSEA analysis indicated that these three genes were positively correlated with myeloid cell enrichment and persistent EBV infection pathway, respectively. Our finding systematically analyzed the difference between AIM and CAEBV and identified TPST1, TNFSF8 and RAB3GAP1 were the key genes in the development of CAEBV.

Pediatric Primary Cutaneous Lymphoma in China: A Retrospective Study

Background: The incidence and clinical features of primary cutaneous lymphoma (PCL) tend to differ by age, gender, geographical, and racial variation. All-aged and adult groups of PCL in various regions have been well demonstrated and compared, while the research concentrating on pediatric PCL is rare, especially in Asian countries. Objective: The aim of this study was to investigate the clinical characteristics of PCL in pediatric population at a single center in China. Methods: We conducted a retrospective study of 101 pediatric cases with PCL, diagnosed at the Institute of Dermatology, Chinese Academy of Medical Sciences, from January 2010 to December 2021. Results: Mycosis fungoides (MF), accounting for 41.6% of the total cases, was the most common subtype in pediatric PCL, and the hypopigmented MF accounted for 47.6% of all the MF cases. Lymphomatoid papulosis and chronic active Epstein-Barr virus infection tied for second place with a proportion of 22.8%. Primary cutaneous anaplastic large cell lymphoma, subcutaneous panniculitis-like T-cell lymphoma, primary cutaneous peripheral T-cell lymphoma, rare subtypes and primary cutaneous B-cell lymphoma, respectively, accounted for 2.0%, 4.0%, 4.0%, and 3.0%. Most patients had favorable prognosis during the follow-up. Conclusion: The study suggested that MF was the most common subtype in pediatric PCL in China, and most types of pediatric PCL had favorable prognosis.

Immunotherapy of Epstein-Barr virus (EBV) infection and EBV-associated hematological diseases with gp350/CD89-targeted bispecific antibody

Acute and persistent infection of Epstein-Barr virus (EBV) is associated with several life-threatening hematological disorders, including lymphoproliferative disorders (LPD), hemophagocytic lymphohistiocytosis (HLH), and chronic active Epstein-Barr virus infection (CAEBV). Currently, there are no efficacious virus-targeted therapies for EBV-driven hematological diseases. To explore the potential of phagocytosis-based immunotherapy, we created a bispecific antibody by targeting the viral envelope protein gp350 with a novel EBV-neutralizing antibody (named R1) that was paired with a monoclonal antibody against CD89 for redirecting macrophages and neutrophils. In vitro study showed that the bispecific antibody enabled efficient phagocytosis of EBV and killing of gp350 + lymphoma cells in the presence of PBMC. In vivo studies in NSG mice inoculated with EBV showed that bispecific antibody dramatically reduced the viral load in blood, solid organs and tissues. Treatment of mice implanted with EBV-harboring Raji lymphoma cells efficiently prevented tumor formation and massive metastasis to solid organs. Treatment of mice implanted with whole blood from EBV-HLH patients was effective in reducing viral levels in blood and solid organ. The gp350/CD89 bispecific antibody was highly effective in clearing EBV and immunotherapy of EBV-driven hematological diseases such as LPD and EBV-HLH.

A Case of Chronic Active Epstein-Barr Virus Infection of External Auditory Canal Mimicking Cellulitis or Malignancy

Epstein-Barr virus (EBV) is an extremely prevalent virus which infects over 90% of the global population at some point in their lifetime. Chronic active EBV infection (CAEBV) is a disease with a high mortality rate with life-threatening complications. Although the main symptom of CAEBV is inflammation, most patients present with fever, hepatic dysfunction with or without hepatomegaly, splenomegaly, lymphadenopathy, thrombocytopenia, anemia, hypersensitivity to mosquito bites, rash, oral ulcers, hemophagocytic syndrome, coronary artery aneurysms, and interstitial pneumonia. Although some cases of CAEBV with other organ symptoms have been reported, CAEBV of external auditory canal and parotid gland is extremely rare. We report a case of CAEBV infection mimicking cellulitis or malignancy diagnosed after a number of biopsies in a patient who presented with a mass accompanied by inflammation in the external auditory canal.

Natural killer cell memory precedes HLH in monozygotic twins discordant for chronic active Epstein-Barr virus disease

Severe mosquito bite allergy (SMBA) is a manifestation of chronic active Epstein-Barr virus (CAEBV) infection defined by necrotic ulceration of the stings. CAEBV with SMBA has a high mortality rate as most patients eventually develop fulminant and refractory hemophagocytic lymphohistiocytosis (HLH). However, how self-resolving SMBA escalates to systemic lethal HLH remains unclear. Through comprehensive immune profiling of a SMBA patient with CAEBV and her healthy monozygotic twin, we found that both twins were seropositive for EBV but showed high discordance in their circulating natural killer (NK) cells. The patient's EBV-infected NK cells displayed memory-like properties, including low CD16, high CD226 and induction of enhanced IFNγ production by IL-2 or IL-12. Her leukocytes also produced high levels of IL-2 and IL-12 when stimulated with salivary gland extract (SGE) specifically from A. albopictus mosquitoes, connected again with hyperproduction of IFNγ by her NK cells. Strikingly, pharmacological inhibition of STAT3 suppressed the NK memory-associated cytokine axis of IFNγ, IL-2 and IL-12 that is generated by A. albopictus SGE stimulation. Altogether, this study shows that NK memory is promoted during CAEBV with SMBA by repeated cytokine restimulation leading up to lethal HLH, and proposes STAT3 as a therapeutic target to halt its progression.

Clinical Significance of Plasma Soluble MICB in Children With EBV-associated Hemophagocytic Lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a potentially fatal systemic inflammation disease in children. The most common cause is Epstein-Barr virus (EBV) infection. MHC class I polypeptide-related sequence B (MICB) is a membrane protein inducibly expressed upon cellular stress, viral infection, or malignant transformation, thus marking these cells for clearance through natural killer group 2 member D-positive lymphocytes. MICB can be released into plasma through several mechanisms, reducing NK cell cytotoxicity. We conducted clinical research on HLH patients and cell research in vitro. In the retrospective clinical part, 112 HLH patients (including EBV-HLH group and non-EBV-HLH group), 7 infectious mononucleosis patients, and 7 chronic active EBV infection patients were treated in Beijing Children's Hospital, affiliated with Capital Medical University, from January 2014 to December 2020, were enrolled in this study. Real-time quantitative polymerase chain reaction, standard enzyme-linked immunosorbent assay methods, and lactate dehydrogenase release tests were used to examine the expression of MICB mRNA, the soluble MICB (sMICB) levels, and the activity of NK cells in those patients. In vitro research, MICB overexpression-vector virus, MICB knockdown-vector virus, and empty-vector virus were transfected into two kinds of target cells, such as K562 and MCF7. The level of sMICB and NK cell killing activity between other groups was compared. Finally, we compared NK92 cell killing activity in different concentrations of sMICB. In clinical studies, compared with the non-EBV-HLH group, the EBV-HLH group had lower NK cell killing activity ( P < 0.05). The level of sMICB in the EBV-HLH group was significantly higher than in non-EBV-HLH, infectious mononucleosis, and chronic active EBV infection patients ( P ＜0.05). A high level of sMICB was associated with poor treatment response and poor prognosis ( P ＜0. 05). Cellular studies showed that an increased level of membrane MICB could positively correlate with the killing activity of NK92 cells ( P ＜0. 05), and a high level of sMICB (1250 to 5000pg/ml) could reduce the killing activity of NK92 cells ( P < 0.05). A high level of sMICB (2500pg/ml) could increase the release of cytokines from NK92 cells. The expression level of sMICB in EBV-HLH patients increased, and a high level of sMICB at the initial onset indicated a poor treatment response. The killing activity of NK cells in EBV-HLH patients decreased more significantly. The high level of sMICB may inhibit the killing activity but increase the release of cytokines of NK92 cells.

Characteristics of plasma Epstein-Barr virus DNA in children with primary infection

Objective: To explore the characteristics of plasma Epstein-Barr virus (EBV) DNA in primary infection in pediatric cases. Methods: The laboratory and clinical data of 571 children diagnosed with EBV primary infection in Children's Hospital of Fudan University during September 1st, 2017 to September 30th, 2018 were retrospectively analyzed. According to the results of plasma EBV DNA, they were divided into positive group and negative group. According to the EBV DNA, they were devided into high plasma virol load group and low plasma virol load group. The Chi-square test, Wilcoxon rank sum test were used to compare the differences between groups. Results: Among the 571 children with EBV primary infection, 334 were males and 237 were females. The age of first diagnosis was 3.8 (2.2, 5.7) years. There were 255 cases in positive group and 316 cases in negative group. The percentage of cases with fever,hepatomegaly and (or) splenomegaly, elevated transaminase in the positive group were higher than those in the negative group (235 cases (92.2%) vs. 255 cases (80.7%), χ2=15.22, P<0.001; 169 cases (66.3%) vs. 85 cases (26.9%), χ2=96.80, P<0.001; and 144 cases (56.5%) vs. 120 cases (38.0%), χ2=18.27, P<0.001; respectively).In the positive group, 70 cases were followed up for 46 (27, 106) days, 68 cases (97.1%) turned negative within 28 days, with the exception of 2 cases (2.9%) developed chronic active EBV infection by follow-up revision.There were 218 cases in high plasma viral DNA copies group and 37 cases in low copies group. More cases presented with elevated transaminases in the high plasma viral DNA copies group than those in the low group (75.7% (28/37) vs. 56.0%(116/207), χ2=5.00, P=0.025).Both the positive rate of EBV DNA in peripheral blood leukocytes (84.2% (266/316) vs. 44.7% (255/571), χ2=76.26, P<0.001) and the copies of EBV DNA (7.0×107 (1.3×107, 3.0×108) vs. 3.1×106 (1.6×106, 6.1×106) copies /L, Z=15.23, P<0.001) were higher than that of plasma. Conclusions: In immunocompetent pediatric cases diagnosed as EBV primary infection, cases with positive plasma EBV DNA were prone to have fever, hepatomegaly and (or) splenomegaly, and elevated transaminase than those with negative plasma viral DNA. The plasma EBV DNA usually turns negative within 28 days after initial diagnosis.Most cases with high viral load in plasma showed elevated aminotransferase.

Salvage Human Leukocyte Antigen-Haploidentical Hematopoietic Cell Transplant With Posttransplant Cyclophosphamide for Graft Failure in a Patient With Chronic Active Epstein-Barr Virus Infection

Salvage human leukocyte antigen-haploidentical hematopoietic cell transplant using posttransplant cyclophosphamide has shown promising results for graft failure in various hematological disorders. However, to our knowledge, no such findings have been reported for a case of chronic active Epstein-Barr virus infection, although graft failure is relatively common in patients with chronic active Epstein-Barr virus infection. We report a case of a 32-year-old woman with natural killer-cell type chronic active Epstein-Barr virus infection who experienced graft failure after a first allogeneic hematopoietic cell transplant from an unrelated human leukocyte antigen-matched donor.The patientreceived a second allogeneic hematopoietic cell transplant with human leukocyte antigen-haploidentical hematopoietic cell transplant using posttransplant cyclophosphamide (cyclophosphamide, 50 mg/kg, on day 3 and day 4) following reduced-intensity conditioning as rescue therapy. Neutrophils successfully engrafted on day 19, and the patient sustained remission without severe transplant-related complication 10 months after salvage human leukocyte antigen- haploidentical hematopoietic cell transplant using posttransplant cyclophosphamide. This report suggests that salvage human leukocyte antigen- haploidentical hematopoietic cell transplant using posttransplant cyclophosphamide may be a feasible therapeutic option for graft failure in patients with chronic active Epstein-Barr virus infection.

PD-1 blockade and lenalidomide combination therapy for chronic active Epstein-Barr virus infection

ObjectivesChronic active Epstein-Barr virus infection (CAEBV) is a prototype of EBV-associated T-or NK-cell lymphoproliferative diseases. It is a disease with poor outcome. Almost all current therapies are ineffective except of allogeneic hematopoietic stem cell transplantation. MethodsWe investigated the efficacy and safety of programmed death 1 (PD-1) blockade (Sintilimab), combined with lenalidomide, which is an immunomodulatory drug, in an open-label, single-center, prospective study involving CAEBV patients. PD1 blockade 2mg/kg was given every two weeks by intravenous infusion on day 1, and lenalidomide 5mg (age<18 years)/10mg (age ≥ 18 years) was given orally once a day on day 1-14. ResultsAs of Nov 15, 2020, 34 patients were enrolled. As of the Feb 1, 2021 analysis cut-off date, 24 cases completed at least 3 courses and were assessed for efficacy. The overall response rate is 54.2% (13/24, 45.8% complete response; 8.3% partial response). EBV-DNA copies in PBMC decreased significantly (p = 0.002). The proportion of CD8+T cells in lymphocytes increased (p = 0.007). The comparative analysis between response group and non-response group showed the proportion of Effector Memory CD8+ T cells and cytokines of CTLs activation (IFN-γ, CD27, CD30, MIG, IP-10) increased significantly in Response-group after treatment. Whole-exome sequencing generated from peripheral blood and saliva samples reveal that Non-Response group had a higher somatic mutational load of copy number variation in background. With a median follow-up time of 17.8 months, 22 of 24 patients were alive with an estimated survival probability of 91.3% at 1 year. All 34 patients were assessed for safety evaluation. The possible drug-related adverse events were reported in 17 (50%) patients. ConclusionsPD-1 blockade combined with lenalidomide was an effective and safe therapy for CAEBV patients. The significant therapeutic effect and the different characteristics between response and non-response group, provides a possible predictive value for CAEBV treatment option.

Kidney involvement of chronic active Epstein-Barr virus infection.

A 54-year-old Japanese woman presented with a fever of unknown origin and renal dysfunction. She had experienced intermittent fever for 10 years, but the frequency increased to a constant fever. Her renal function had gradually deteriorated over the past year, and serum creatinine and urinary α1-microglobulin levels were elevated to 2.23 mg/dL and 113 mg/L, respectively. Physical and laboratory examinations were unremarkable, except for mild anemia and elevated serum creatinine levels. Analysis of peripheral blood lymphocyte subsets showed 59% CD3, 35% CD4 and 31% CD8. Epstein-Barr virus (EBV) serology showed elevated levels of EBV capsid antigen IgG and EBV nuclear antigen (1:1280 and 1:40, respectively). Plasma EBV-DNA level was 5.63 log IU/mL, and an oligoclonal band was detected by Southern blot hybridization of EBV terminal repeat analysis. Quantification of EBV-DNA in peripheral lymphocyte subset using magnetic beads showed that EBV predominantly resided in CD4+ T-cells. (CD4, 258,768; CD8, 27,738; and CD56, 23,369; IU/µgDNA, respectively). T-cell receptor α gene rearrangement was undetected. Based on the above, she was diagnosed with chronic active EBV infection (CAEBV). 18F-fluorodeoxyglucose positron emission tomography/computerized tomography showed bilateral kidney enlargement and mildly enhanced uptake (maximum standardized uptake value 4.08 g/mL) (Figure 1 top left). Kidney biopsy specimen stained with hematoxylin and eosin showed diffuse tubulointerstitial infiltration of small to medium-sized lymphocytes in the renal parenchyma (Figure 1 top right). Massive infiltration of CD4+ T-cells was documented by immunohistochemical staining (Figure 1 bottom left). Furthermore, EBV-infected cells were detected by in situ hybridization with EBV-encoded RNA (EBER) (Figure 1 bottom right). Immunostaining of EBV nuclear antigen-2 and latent membrane protein 1 were negative. EBER-positive cells were distributed in the same region as CD4+ T-cells, consistent with the predominant presence of EBV-DNA in CD4+ T-cells. Her renal function had improved after initiating chemotherapy, and she is scheduled for hematopoietic stem cell transplantation. The clinical features of EBV infection vary according to the type of EBV-infected cells. The predominant EBV-infected cells in EBV-induced hemophagocytic lymphohistiocytosis are CD8+ T cells, whereas in CAEBV, CD4+ T cells are predominantly infected. Although rare, renal invasion of EBV should be considered in cases with renal impairment, and its clinical significance needs to be investigated. AF and SS wrote and edited the manuscript, provided patient care and reviewed the literature. KS and MT provided patient care. TS and KM wrote and edited the manuscript. All authors reviewed and approved the final version of the manuscript We thank Dr. Yuka Torii (Department of Pediatrics, Nagoya University, Japan) for quantification of the EBV viral load of lymphocyte subsets using magnetic beads. We also thank Dr. Hiroshi Kimura (Department of Virology, Nagoya University, Japan) for his helpful advice on patient care. We appreciate the staff of the Department of Hematology, Kameda Medical Center for providing patient care. We thank Editage (www.editage.jp) for English language editing. The authors declare they have no conflicts of interest. The authors received no specific funding for this work. This study was conducted according to the Declaration of Helsinki, and written consent was obtained from the patient for this report. The patient provided written informed consent for the publication of this case, with the removal of all identifying information to ensure anonymity and maintain privacy. The data that support the findings of this study are available from the corresponding author upon reasonable request. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.