Chronic Active Epstein-Barr Virus Infection: The Elucidation of the Pathophysiology and the Development of Therapeutic Methods

A differential diagnosis method for systemic CAEBV and the prospect of EBV-related immune cell markers via flow cytometry

Chronic active Epstein-Barr virus (CAEBV) infection of the T-cell or Natural killer (NK)-cell type, systemic form (systemic CAEBV or sCAEBV) was defined by the WHO in 2017 as an EBV-related lymphoproliferative disorder and is listed as an EBV-positive T-cell and NK-cell proliferation. The clinical manifestations and prognoses are heterogeneous. This makes systemic CAEBV indistinguishable from other EBV-positive T-cell and NK-cell proliferations. Early diagnosis of systemic CAEBV and early hematopoietic stem cell transplantation can improve patient prognosis. At present, the diagnosis of systemic CAEBV relies mainly on age, clinical manifestations, and cell lineage, incurring missed diagnosis, misdiagnosis, long diagnosis time, and inability to identify high-risk systemic CAEBV early. The diagnostic methods for systemic CAEBV are complicated and lack systematic description. The recent development of diagnostic procedures, including molecular biological and immunological techniques such as flow cytometry, has provided us with the ability to better understand the proliferation of other EBV-positive T cells and NK cells, but there is no definitive review of their value in diagnosing systemic CAEBV. This article summarizes the recent progress in systemic CAEBV differential diagnosis and the prospects of flow cytometry.

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

BACKGROUND

Chronic 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.

METHODS

A 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.

RESULTS

Three 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.

CONCLUSION

Our 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.

Chronic Active Epstein-Barr Virus (EBV) Infection Controlled by Allogeneic Stem Cell Transplantation and EBV-Specific T Cells

We report sustained remission of chronic active Epstein-Barr virus (EBV) infection in a 27-year-old female patient treated with third-party EBV-specific T cells followed by allogeneic hematopoietic stem cell transplantation (HSCT). The viremia cleared after administration of anti-T-lymphocyte globulin for graft-versus-host disease (GvHD) prophylaxis. Subsequent expansion of EBV-infected host T cells was controlled by transfusion of donor-derived EBV-specific T cells.

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.

Clinical Analysis of Chronic Active Epstein-Barr Virus Infection Involving the Gastrointestinal Tract

BACKGROUND

Chronic active Epstein‒Barr virus infection (CAEBV) is an intractable and progressive disease. T cells or NK cells infected by EBV can proliferate and infiltrate into multiple organs. CAEBV combined with gastrointestinal involvement is a rare clinical disease that has not been well described, and sometimes it may clinically mimic gastroenteritis or inflammatory bowel disease.

METHODS

This was an observational study that included all pediatric CAEBV patients who were treated at Beijing Children's Hospital, Capital Medical University, from June 2017 to June 2021. Patients were divided into the case group and the control group according to whether these patients had GI involvement. The children's clinical manifestations, laboratory and ultrasound examinations, treatment and prognosis were observed.

RESULTS

Seventy-two patients were enrolled in this study. Fifteen patients had GI involvement, including 11 males and 4 females, accounting for 20.8%, with a median onset age of 3.71 (0.64-14.47) years. The most common clinical manifestation at onset was diarrhea (13/15). Gastrointestinal ultrasound showed pneumatosis intestinalis, mild to moderate swelling of the surrounding mesentery and omentum and enhancement on ultrasound. The endoscopic features were hyperemia, edema and ulcers of variable morphological characteristics. Pathological examination showed lymphocyte infiltration with EBV-encoded small RNA (+), and the common locations of involvement were the colon (n = 6) and gastric antrum (n=3). The median follow-up time was 13.26 (0.31-51.89) months. Ten patients survived, and 5 patients died (including 1 who died of intestinal perforation because of necrotizing enterocolitis). Compared with the control group, the case group had higher alanine aminotransferase levels, aspartate aminotransferase and whole blood EBV-DNA copies (P = 0.038, 0.040 and < 0.001) and lower natural killer cell activity (P < 0.001). The 3-year overall survival rate of the case group was significantly lower than that of the control group (59.3% ± 12.9% vs. 79.4% ± 4.9%, P = 0.021).

CONCLUSION

The incidence of CAEBV with GI involvement was low. The most common location of involvement was the colon. CAEBV with GI involvement had a poor prognosis. Patients with high whole blood EBV-DNA copy levels early in their illness were more likely to develop GI involvement.

Chronic active Epstein-Barr virus infection involving gastrointestinal tract with hemophagocytic lymphohistiocytosis

Chronic active EBV infection (CAEBV) is a lymphoproliferative disorder of T- or NK-cell type in Asian countries. CAEBV involving the gastrointestinal tract (GI CAEBV) is a rare condition with poor prognosis that may rapidly progress with hemophagocytic lymphohistiocytosis (HLH) and life-threatening complications such as GI bleeding and/or perforation. The approach to CAEBV with GI tract involvement (GI CAEBV) is still an unmet clinical need. In this case series study, we summarized the clinical features, treatment, and prognosis of seven cases of GI CAEBV with HLH, particularly focusing on its prognosis and the possible salvage therapy combining surgery, novel therapeutic agents, and/or autologous(auto-) hematopoietic stem cell transplantation (HSCT) based on successful cases from our center. GI CAEBV is often misdiagnosed as inflammatory bowel diseases and certain infections. The key to its early recognition is the integrative consideration of its systemic manifestation, serum virology, endoscopic, and imaging findings along with pathology. Surgical intervention should not be hesitated when life-threatening GI complications occur. Resection of the involved bowel segment is an effective way of controlling bleeding and reducing tumor burden. In addition to upfront allogeneic HSCT, new therapeutic modalities including PD-1 antibody and auto-HSCT may be effective in certain patients.

Genomic profiling for clinical decision making in lymphoid neoplasms

With the introduction of large-scale molecular profiling methods and high-throughput sequencing technologies, the genomic features of most lymphoid neoplasms have been characterized at an unprecedented scale. Although the principles for the classification and diagnosis of these disorders, founded on a multidimensional definition of disease entities, have been consolidated over the past 25 years, novel genomic data have markedly enhanced our understanding of lymphomagenesis and enriched the description of disease entities at the molecular level. Yet, the current diagnosis of lymphoid tumors is largely based on morphological assessment and immunophenotyping, with only few entities being defined by genomic criteria. This paper, which accompanies the International Consensus Classification of mature lymphoid neoplasms, will address how established assays and newly developed technologies for molecular testing already complement clinical diagnoses and provide a novel lens on disease classification. More specifically, their contributions to diagnosis refinement, risk stratification, and therapy prediction will be considered for the main categories of lymphoid neoplasms. The potential of whole-genome sequencing, circulating tumor DNA analyses, single-cell analyses, and epigenetic profiling will be discussed because these will likely become important future tools for implementing precision medicine approaches in clinical decision making for patients with lymphoid malignancies.

Allogeneic hematopoietic stem cell transplantation with the modified myeloablative conditioning regimen for children with chronic active Epstein-Barr virus infection

Importance

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is considered the only effective treatment for chronic active Epstein-Barr virus infection (CAEBV). The clinical efficacy and safety of allo-HSCT with different conditioning regimens in children with CAEBV remain unclear.

Objective

To evaluate the effectiveness and safety of allo-HSCT with the modified myeloablative conditioning (MAC) regimen for children with CAEBV and also the factors affecting the outcomes.

Methods

We retrospectively analyzed children with CAEBV who underwent allo-HSCT with the modified MAC regimen at Beijing Children's Hospital, Capital Medical University from October 2016 to June 2021. Data related to the clinical manifestations, engraftment, and outcome were extracted from the medical records.

Results

The cohort comprised 41 patients (24 males, 17 females) with a median transplantation age of 92.6 (60.4, 120.7) months and a median follow-up time of 28.2 (15.3, 40.2) months. Four patients (9.8%) died, among which three died from primary disease relapse, and one died from grade IV acute graft-versus-host diseases (aGVHD) after stopping treatment. The 3-year overall survival (OS) and 3-year event-free survival (EFS) rates were 88.8% ± 5.4% and 85.0% ± 5.7%, respectively. The 3-year OS and EFS did not significantly differ between the patients with hemophagocytic lymphohistiocytosis (HLH) and the patient without HLH (87.7% ± 6.8% vs. 91.7% ± 8.0%, P = 0.790; 85.0% ± 6.9% vs. 84.6% ± 10.0%, P = 0.921), or among the patients with complete remission, partial remission, and activity disease before HSCT (all P > 0.05). Multivariate analysis showed that grade III-IV aGVHD was a risk factor for mortality (Hazards ratio: 11.65, 95% confidence interval: 1.00, 136.06; P = 0.050).

Interpretation

Allo-HSCT with the modified MAC regimen is safe and effective for pediatric CAEBV. This treatment benefits patients with HLH or active disease. Patients with Grade III-IV aGVHD may be associated with worse outcomes.

A rare B-cell type chronic active Epstein-Barr virus infection patient mimicking lymphoma on 18F-FDG PET/CT and literature review

A 13-year-old girl suffered from worsen snoring and persistent bilateral nasal congestion for one year. Paranasal sinus computed tomography (CT) and magnetic resonance imaging (MRI) found nasopharyngeal passages and sinus were occupied with soft tissues and bilateral neck enlarged lymph nodes 6 months ago. Tumor markers were normal. The titers of anti-Epstein-Barr virus (EBV) IgM, anti-EBV IgG, early antigen (EA) IgG, and Epstein-Barr nuclear antigen (EBNA) IgG increased. 2-Deoxy-2-[fluorine-18]-fluoro-D-glucose (¹⁸F-FDG) positron emission tomography combined with CT (PET/CT) revealed thickened soft tissues in nasopharynx and oropharynx, enlarged multiple lymph nodes in the neck, bilateral armpits, abdominal cavity and retroperitoneum, and pelvic cavity, diffuse thickening of the gastric wall of the antrum with hypermetabolism. According to the age, situation, regions, and abnormal FDG uptake, an initial diagnosis of EBV-related lymphoma was made. However, the pathological results of the nasopharyngeal mass and the abdominal lymph node confirmed the final diagnosis of a B-cell type chronic active Epstein-Barr virus disease (CAEBV), a rare type of EBV associated lymphoproliferative disorder (LPD). After receiving adoptive immune cells therapy, the EBV load decreased. At present, the patient is being followed up.

Treatment Advances in EBV Related Lymphoproliferative Diseases

Epstein Barr virus (EBV) can affect 90% of the human population. It can invade B lymphocytes, T lymphocytes and natural killer cells of the host and remain in the host for life. The long latency and reactivation of EBV can cause malignant transformation, leading to various lymphoproliferative diseases (LPDs), including EBV-related B-cell lymphoproliferative diseases (EBV-B-LPDs) (for example, Burkitt lymphoma (BL), classic Hodgkin's lymphoma (cHL), and posttransplantation and HIV-related lymphoproliferative diseases) and EBV-related T-cell lymphoproliferative diseases (EBV-T/NK-LPDs) (for example, extranodal nasal type natural killer/T-cell lymphoma (ENKTCL), aggressive NK cell leukaemia (ANKL), and peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). EBV-LPDs are heterogeneous with different clinical features and prognoses. The treatment of EBV-LPDs is usually similar to that of EBV-negative lymphoma with the same histology and can include chemotherapy, radiotherapy, and hematopoietic stem cell transplant (HSCT). However, problems such as serious toxicity and drug resistance worsen the survival prognosis of patients. EBV expresses a variety of viral and lytic proteins that regulate cell cycle and death processes and promote the survival of tumour cells. Based on these characteristics, a series of treatment strategies for EBV in related malignant tumours have been developed, such as monoclonal antibodies, immune checkpoint inhibitors, cytotoxic T lymphocytes (CTLs) and epigenetic therapy. These new individualized therapies can produce highly specific killing effects on tumour cells, and nontumour cells can be protected from toxicity. This paper will focus on the latest progress in the treatment of EBV-LPDs based on pathological mechanisms.

The superiority of Epstein-Barr virus DNA in plasma over in peripheral blood mononuclear cells for monitoring EBV-positive NK-cell lymphoproliferative diseases

Epstein-Barr virus (EBV), characterized as an omnipresent virus, has been found able to infect NK cells and leads to NK-cell type EBV-positive lymphoproliferative diseases (EBV-NK-LPDs). We retrospective analysed 202 EBV-NK-LPDs (including 64 CAEBV-NK, 27 ANKL, and 111 ENKTL) patients' relationships between EBV DNA copies laboratory test results and clinical features. In CAEBV-NK cohort, EBV DNA loads in either plasma or PBMCs had significant differences between the active state and the inactive state. Receiver operating characteristic (ROC) curves were used to measure the diagnosis accuracy of EBV DNA copies. After comparing the area under the curve (AUC), EBV DNA loads in plasma had significantly higher accuracy in distinguishing disease activation than in PBMCs. Therefore, we propose redefining CAEBV-NK diagnosis criteria as increased EBV DNA copies in plasma (over 7.1×10² copies/ml) instead of in peripheral blood. In ANKL and ENKTL cohorts, patients who received effective therapy had significantly lower EBV DNA copies in plasma & PBMCs than in those with ineffective therapy. The significant and consistent decline indicated EBV DNA loads in plasma being a more sensitive biomarker in monitoring EBV-NK-LPDs therapy responses. Hemophagocytic lymphohistiocytosis (HLH) can occur secondary to EBV-NK-LPDs, mostly associated with a poor prognosis, so we try to estimate the combination of HLH by monitoring EBV DNA copies. When comparing the ROC curves of EBV DNA copies, EBV DNA loads in plasma had higher diagnosis accuracy. When the copies level over 4.16×10³ copies/ml, it might indicate combining with HLH. This article is protected by copyright. All rights reserved.

A study of Ruxolitinib-response-based stratified treatment for pediatric hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a lethal disorder characterized by hyperinflammation. Recently, ruxolitinib, targeting key cytokines in HLH, has shown promise for HLH treatment. However, there is a lack of robust clinical trials evaluating its efficacy, especially its utility as a front-line therapy. In this study (www.chictr.org.cn, ChiCTR2000031702), we designed ruxolitinib as a first-line agent for pediatric HLH and stratified the treatment based on its early response. Fifty-two newly diagnosed patients were enrolled. The overall response rate (ORR) of ruxolitinib monotherapy (day-28) was 69.2% (36/52), with 42.3% (22/52) achieving sustained complete remission (CR). All responders achieved their first response to ruxolitinib within 3-days. The response to ruxolitinib was significantly associated with the underlying etiology at enrollment (p=0.009). EBV-HLH patients were most sensitive to ruxolitinib, with an ORR of 87.5% (58.3% in CR). After ruxolitinib therapy, 57.7% (30/52) of the patients entered intensive therapy with additional chemotherapy. Among them, 53.3% (16/30) patients achieved CR, and 46.7% (14/30) patients dominated by chronic active Epstein Barr virus infection-associated HLH (CAEBV-HLH) developed refractory HLH by week-8. The median interval to additional treatment since first ruxolitinib administration was 6-days (range, 3-25). Altogether, 73.1% (38/52) of the enrolled patients achieved CR after treatment overall. The 12-month overall survival for all patients was 86.4% (95%CI, 77.1%-95.7%). Ruxolitinib had low toxicity and was well tolerated compared to intensive chemotherapy. Our study provides clinical evidence for ruxolitinib as a front-line agent for pediatric HLH. The efficacy was particularly exemplified with stratified regiment based on the early differential response to ruxolitinib. This study was registered in the Chinese Clinical Trials Registry Platform (http://www.chictr.org.cn/) as ChiCTR2000031702.

Anti-viral triterpenes: a review

Triterpenes are naturally occurring derivatives biosynthesized following the isoprene rule of Ruzicka. The triterpenes have been reported to possess a wide range of therapeutic applications including anti-viral properties. In this review, the recent studies (2010-2020) concerning the anti-viral activities of triterpenes have been summarized. The structure activity relationship studies have been described as well as brief biosynthesis of these triterpenes is discussed.

Lessons from Epstein-Barr virus DNA detection in cerebrospinal fluid as a diagnostic tool for EBV-induced central nervous system dysfunction among HIV-positive patients

Polymerase chain reaction (PCR) analysis of Epstein-Barr virus (EBV) DNA in cerebrospinal fluid (CSF) remains vital for evaluating active EBV infection involving the central nervous system (CNS). CSF EBV DNA was often found in conjunction with other microbial infection affecting the CNS among patients infected with human immunodeficiency virus (HIV). Sometimes CSF EBV DNA is detectable in patients without neurological symptoms. This review focused on the clinical and laboratory features of CNS EBV infection among patients with HIV, and discussed various types of EBV-associated CNS infections, and predominant neoplasms involving CNS such as primary central nervous system lymphoma (PCNSL), CNS-non-Hodgkin's lymphoma, smooth muscle tumors and leiomyosarcomas, EBV encephalitis or myelitis, EBV meningitis and EBV coinfection with other causative agents were also included. Furthermore, the metagenomic next-generation sequencing technique with high sensitivity for the detection of pathogenic coinfection in the CSF were also reviewed. We concluded that CSF EBV-DNA detection with high sensitivity and specificity could be a useful diagnostic tool for CNS lymphoma among HIV patients; however, it is still unknown for other CNS diseases. We further summarized and conclude that positive CSF EBV-DNA detection combined with specific brain focal lesions could be a minimally invasive method to diagnose PCNSL. The occurrence of positive CSF EBV-DNA was influenced by PCR detection limit, PCR methods, immunocompromised status, the possible influence of anti-herpetic therapy and anti-HIV therapy, and the size and location of a tumor mass. Uniform PCR methods as vital diagnostic tools and optimal EBV-DNA load threshold need to be established.