Lymphocytes in Patients with Chronic Active Epstein-Barr Virus Disease Exhibited Elevated PD-1/PD-L1 Expression and a Prevailing Th2 Immune Response.

Background And Objectives: Chronic active Epstein-Barr virus disease (CAEBV) is a proliferative disease of EBV+ T or natural killer (NK) cells with an unclear pathogenesis. This study aimed to examine the frequency and exhaustion levels of lymphocyte subsets in patients with CAEBV to further investigate the pathogenesis. Methods: Using flow cytometry, we detected the frequency, expression levels of programmed cell death 1 (PD-1) and programmed death ligand 1 (PD-L1), and EBV infection status of peripheral T subsets and NK cells in patients with CAEBV and healthy individuals. Results: 24 patients and 15 healthy individuals were enrolled in this study. Patients showed notably higher expression levels of PD-1 and PD-L1 in peripheral T subsets and NK cells compared to healthy individuals (P < 0.05). EBV+ lymphocytes exhibited significantly higher PD-L1 expression levels than EBV- lymphocytes. Additionally, the frequency of effector memory T (Tem) cells was significantly increased in patients, and the PD-L1 expression level was positively correlated with the EBV load. Besides, helper T cell 2 (Th2) immune bias, also favoring EBV amplification, was found in patients, including increased Th2 cell frequency, enhanced response capacity, and elevated serum levels of associated cytokines. The distribution and PD-1 expression levels of peripheral T subsets returned to normal in patients who responded to PD-1 blockade therapy. Conclusions: The up-regulation of the PD-1/PD-L1 pathway of peripheral T and NK cells and Th2 immune predominance jointly promoted EBV replication and the development of CAEBV. PD-1 blockade therapy reduced the PD-1 expression level of lymphocytes and helped normalize the distribution of the T subsets.

Chronic active Epstein-Barr virus disease originates from infected hematopoietic stem cells.

ABSTRACT: Chronic active Epstein-Barr virus (EBV) disease (CAEBV) is a lethal syndrome because of persistent EBV infection. When diagnosed as CAEBV, EBV infection was observed in multiple hematopoietic lineages, but the etiology of CAEBV is still elusive. Bone marrow and peripheral cells derived from 5 patients with CAEBV, 1 patient with EBV-associated hemophagocytic lymphohistiocytosis, and 2 healthy controls were analyzed. Multiple assays were applied to identify and characterize EBV-infected cells, including quantitative polymerase chain reaction, PrimeFlow, and single-cell RNA-sequencing (scRNA-seq). Based on scRNA-seq data, alterations in gene expression of particular cell types were analyzed between patients with CAEBV and controls, and between infected and uninfected cells. One patient with CAEBV was treated with allogeneic hematopoietic stem cell transplantation (HSCT), and the samples derived from this patient were analyzed again 6 months after HSCT. EBV infected the full spectrum of the hematopoietic system including both lymphoid and myeloid lineages, as well as the hematopoietic stem cells (HSCs) of the patients with CAEBV. EBV-infected HSCs exhibited a higher differentiation rate toward downstream lineages, and the EBV infection had an impact on both the innate and adaptive immunity, resulting in inflammatory symptoms. EBV-infected cells were thoroughly removed from the hematopoietic system after HSCT. Taken together, multiple lines of evidence presented in this study suggest that CAEBV disease originates from the infected HSCs, which might potentially lead to innovative therapy strategies for CAEBV.

SPOP inhibits HBV transcription and replication by ubiquitination and degradation of HNF1α.

Hepatitis B virus (HBV) infection remains a significant public health burden worldwide. The persistence of covalently closed circular DNA (cccDNA) within the nucleus of infected hepatocytes is responsible for the failure of antiviral treatments. The ubiquitin proteasome system (UPS) has emerged as a promising antiviral target, as it can regulate HBV replication by promoting critical protein degradation in steps of viral life cycle. Speckle-type POZ protein (SPOP) is a critical adaptor for Cul3-RBX1 E3 ubiquitin ligase complex, but the effect of SPOP on HBV replication is less known. Here, we identified SPOP as a novel host antiviral factor against HBV infection. SPOP overexpression significantly inhibited the transcriptional activity of HBV cccDNA without affecting cccDNA level in HBV-infected HepG2-NTCP and primary human hepatocyte cells. Mechanism studies showed that SPOP interacted with hepatocyte nuclear factor 1α (HNF1α), and induced HNF1α degradation through host UPS pathway. Moreover, the antiviral role of SPOP was also confirmed in vivo. Together, our findings reveal that SPOP is a novel host factor which inhibits HBV transcription and replication by ubiquitination and degradation of HNF1α, providing a potential therapeutic strategy for the treatment of HBV infection.

Modified DEP regimen as induction therapy for lymphoma-associated hemophagocytic lymphohistiocytosis: a prospective, multicenter study.

PURPOSE: Hemophagocytic lymphohistiocytosis (HLH), especially lymphoma-associated HLH (LA-HLH), is a refractory immune disorder with high mortality. There is still no consensus regarding the ideal treatment for LA-HLH. METHODS: We performed a prospective multicenter study (NCT04077905) to explore the efficacy of a modified DEP regimen as induction therapy for LA-HLH. Twenty-eight patients from 6 clinical centers in China were enrolled between September 2019 and July 2021. We evaluated the efficacy of the modified DEP induction therapy 4 weeks after the initiation of treatment. RESULTS: The results showed that the overall response rate was 89.3% (25/28 patients), whereby 28.6% (8/28 patients) achieved a complete response and 60.7% (17/28 patients) were in partial response. Ferritin and soluble CD25 levels were decreased significantly 4 weeks after the modified DEP induction therapy (P = 0.001 and P = 0.00016, respectively), while platelet count and total bilirubin improved significantly (P = 0.004 and P = 0.001, respectively). The 1-year overall survival rate of all patients was 34.5%, with a median survival of 6.5 months (range 0.5-19 months). Patients with LA-HLH who underwent a stem cell transplantation had a significantly better prognosis than those not achieving complete response 4 weeks after modified DEP induction therapy (P = 0.034). CONCLUSION: Our study suggests that the modified DEP regimen is a safe and effective induction therapy for LA-HLH. Timely stem cell transplantation can improve the prognosis of patients with LA-HLH. TRAIL REGISTRY NUMBER: NCT04077905. URL: https://clinicaltrials.gov/ct2/show/NCT04077905?id=NCT04077905&draw=2&rank=1 .

Massive pericardial effusion due to chronic active Epstein-Barr virus infection successfully treated with PD-1 blockade: A case report.

RATIONALE: Chronic active Epstein-Barr virus (EBV) infection (CAEBV) is a rare but life-threatening EBV-positive lymphoproliferative disorder. Currently, treatment options for CAEBV are limited. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only way to cure CAEBV. Here, we report a rare case of CAEBV manifesting as massive pericardial effusion that was successfully treated with programmed cell death protein-1 (PD-1) blockade immunotherapy. PATIENT CONCERNS: A 36-year-old woman with intermittent chest distress and dyspnea for 8 months was admitted to our center on October 25, 2021. Laboratory tests showed leukocytopenia and elevated liver enzyme levels. Initial echocardiography revealed massive pericardial effusion. DIAGNOSIS: High levels of EBV-DNA were detected in the pericardial fluid by metagenomic next-generation sequencing. The pathological diagnosis of her left inguinal lymph node and skin lesions revealed systemic CAEBV. INTERVENTIONS: The patient received sintilimab injection at a dose of 200 mg every 2 weeks in combined with lenalidomide 10 mg once daily. OUTCOMES: The patient achieved complete resolution of pericardial effusion 5 months after PD-1 blockade immunotherapy without apparent adverse effects. LESSONS: CAEBV is a rare but life-threatening EBV-positive lymphoproliferative disease. We present a rare case of massive pericardial effusion caused by systemic CAEBV, which was successfully treated with sintilimab. This case highlights the promising curative effect of PD-1 blockade immunotherapy in systemic CAEBV, especially for patients not suitable for allo-HSCT.

Successful Treatment of Relapsed Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis After Allo-HSCT with PD-1 Blockade: A Case Report.

Background: Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is a rare and aggressive disease with high mortality and poor prognosis. To date, allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the only way to cure EBV-HLH. However, relapse of EBV-HLH after allo-HSCT is common and remains a major challenge. Case Presentation: A 22-year-old woman with persistent fever for a month presented to our center with EBV-HLH. After induction of remission using two cycles of the L-DEP (PEG-aspargase, liposomal doxorubicin, etoposide, and high-dose methylprednisolone) regimen, the patient underwent an human leukocyte antigen (HLA)-identical sibling allo-HSCT. However, she experienced disease relapse soon after the procedure, and none of the possible treatment options achieved a sustained response. Finally, she received a sintilimab injection and achieved complete resolution of EBV-HLH. Conclusion: We summarize a case of relapsed EBV-HLH after allo-HSCT that was successfully treated with a programmed cell death protein-1 (PD-1) antibody. Further studies are needed to determine whether PD-1 blockade has therapeutic potential for relapsed EBV-HLH after allo-HSCT.

Polyserositis as a primary clinical manifestation of CD7+ acute myelogenous leukemia with myeloid sarcoma: A case report.

RATIONALE: Myeloid sarcomas (MS) are defined as rare extramedullary masses composed of immature myeloid cells. MS mostly develops in patients with acute myeloid leukemia (AML), and involves primarily the skin, soft tissues, bones, and lymph nodes. Pleura and pericardium involvement of MS are extremely uncommon. Polyserositis is also a very rare extramedullary presentation of acute myeloid leukemia (AML). PATIENT CONCERNS: A 30-year-old woman with a complaint of right neck mass combined with coughing for 2 months as well as fever and systemic edema for the last 10 days, was admitted to our center on July 11, 2019. Initial positron emission tomography (PET) scan indicated systemic lymphadenopathy, bilateral pleural effusion, and pericardial effusion. DIAGNOSIS: The initial pathological diagnosis of lymph nodes was MS. Subsequent bone marrow analysis confirmed AML. INTERVENTIONS: Conventional IA induction regimen followed by high-dose cytarabine (HiDAC) regimen. OUTCOMES: Complete absorption of pericardial and pleural effusion after the first cycle of IA induction chemotherapy. LESSONS: Polyserositis can be an extramedullary presentation of AML. Patients with polyserositis should undergo routine flow cytometric analysis. For AML with extamedullary infiltration, systemic chemotherapy should be administered in all confirmed cases.

Cumulated Ca2⁺ spike duration underlies Ca2⁺ oscillation frequency-regulated NFκB transcriptional activity.

[Ca(2+)](i) oscillations drive downstream events, like transcription, in a frequency-dependent manner. Why [Ca(2+)](i) oscillation frequency regulates transcription has not been clearly revealed. A variation in [Ca(2+)](i) oscillation frequency apparently leads to a variation in the time duration of cumulated [Ca(2+)](i) elevations or cumulated [Ca(2+)](i) spike duration. By manipulating [Ca(2+)](i) spike duration, we generated a series of [Ca(2+)](i) oscillations with the same frequency but different cumulated [Ca(2+)](i) spike durations, as well as [Ca(2+)](i) oscillations with the different frequencies but the same cumulated [Ca(2+)](i) spike duration. Molecular assays demonstrated that, when generated in 'artificial' models alone, under physiologically simulated conditions or repetitive pulses of agonist exposure, [Ca(2+)](i) oscillation regulates NFκB transcriptional activity, phosphorylation of IκBα and Ca(2+)-dependent gene expression all in a way actually dependent on cumulated [Ca(2+)](i) spike duration whether or not frequency varies. This study underlines that [Ca(2+)](i) oscillation frequency regulates NFκB transcriptional activity through cumulated [Ca(2+)](i) spike-duration-mediated IκBα phosphorylation.