Chronic Epstein-Barr viral load carriage after pediatric organ transplantation.

Epstein-Barr virus (EBV) infection and EBV-associated post-transplant lymphoproliferative disorder (EBV/PTLD) is one of the most devastating complications occurring in pediatric solid organ transplant (SOT) recipients. Observations of SOT recipients undergoing serial EBV monitoring to inform reduction of immune suppression to prevent EBV-/PTLD has identified patients who maintain chronic high EBV load (CHL) in their blood. The CHL carrier state has been seen more commonly in pediatric compared to adult transplant recipients. Some but not all CHL may progress to EBV/PTLD. However, little is known regarding the biology of this CHL carrier state and the optimal clinical approach to CHL has not been established. This review summarizes the current knowledge and evidence of chronic high EBV load and introduces commonly adopted approaches from experts in this field.

Safety and antibody response of the BNT162b2 SARS-CoV-2 vaccine in children aged 5-11 years with underlying diseases: A prospective observational study.

BACKGROUND: Data on the safety and antibody response of the BNT162b2 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine in children aged 5-11 years with underlying diseases are limited. Thus, our study aimed to address this gap. METHODS: This prospective observational study investigated the antibody titers for SARS-CoV-2 spike protein receptor-binding domain (S-IgG) and nucleocapsid protein (N-IgG) in patients aged 5-11 years with chronic underlying diseases following two doses of BNT162b2. Additionally, a questionnaire was used to assess adverse events (AEs) arising within 7 days after each dose. Data on severe AEs arising within 28 days after each dose were extracted from the patients' electronic medical records. RESULTS: Among 122 patients, 24.6% (30/122) were immunocompromised. Furthermore, 79 patients experienced at least one AE following vaccination, but all recovered without sequelae, including one severe case after the first dose. The seropositivity rate after the second dose was 99.1% (116/117). Excluding 19 N-IgG-positive patients, the geometric mean antibody titer (GMT) was significantly higher in immunocompetent patients than in immunocompromised patients (1496 U/mL [95% confidence interval 1199-1862] vs. 472 U/mL [200-1119], p = 0.035). Additionally, the GMT of S-IgG was higher in N-IgG-positive patients than in N-IgG-negative patients (8203 [5847-11482] U/mL vs. 1127 [855-1486] U/mL, p < 0.001). CONCLUSIONS: BNT162b2 is acceptably safe and immunogenic for children aged 5-11 years with underlying diseases. Although seroconversion was satisfactory in immunocompromised patients, the titers were lower than in immunocompetent patients.

A Focused Review of Epstein-Barr Virus Infections and PTLD in Pediatric Transplant Recipients: Guidance From the IPTA and ECIL Guidelines.

Epstein-Barr Virus (EBV) diseases, including EBV-associated post-transplant lymphoproliferative disorder (PTLD) remain important causes of morbidity and mortality in children undergoing solid organ transplantation (SOT) and hematopoietic cell transplantation (HCT). Despite progress in the prevention of EBV disease including PTLD (EBV/PTLD) in HCT, key questions in the prevention, and management of these infectious complications remain unanswered. The goal of this manuscript is to highlight key points and recommendations derived from the consensus guidelines published by the International Pediatric Transplant Association and the European Conference on Infections in Leukemia for children undergoing SOT and HCT, respectively. Additionally, we provide background and guidance on the use of EBV viral load measurement in the prevention and management of these children.

Association between use of antipyretics and antibody titers after two doses of the BNT162b2 SARS-CoV-2 vaccine in adolescents and young adults with underlying diseases.

There are few reports on the association between antipyretic use and antibody titers in adolescents and young adults following SARS-CoV-2 vaccination. Multivariable linear regression analyses were performed to examine the association between antipyretic use and antibody titers. The use of antipyretics was not associated with antibody titers (ß coefficient [95% CI] = -0.107 [-0.438 to 0.224]).

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 ≥ 10,000 IU/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.

No Additional Risk of Ampicillin Rash Among Pediatric Liver Transplant Recipients With Concurrent Epstein-Barr Virus Infection.

BACKGROUND: Epstein-Barr virus (EBV) infection frequently develops in children undergoing liver transplantation (LT) because of mandated immunosuppressive therapy. There is a risk of ampicillin rash when penicillin derivatives are used in patients with EBV-associated infectious mononucleosis. Hence, the administration of penicillin derivatives may raise concerns about ampicillin rash in patients with high EBV loads. However, no studies confirmed the risk of administering penicillin derivatives to EBV-infected children after LT. METHODS: This retrospective study was conducted at the largest pediatric transplantation center in Japan. We investigated all pediatric liver transplant recipients who received penicillin derivatives within 2 years of LT between 2014 and 2020. We separated the cohort into EBV-positive and EBV-negative groups to assess the frequency of ampicillin and antibiotic-associated rash. RESULTS: Two hundred eighty-six liver transplant recipients were enrolled. There were 111 recipients in the EBV-positive group and 175 recipients in the EBV-negative group. In the EBV-positive group, 49 patients had high EBV DNA loads (≥1000 copies/µg DNA). None of the patients in either group developed ampicillin rash, and the frequency of antibiotic-associated rash did not differ [8/111 (7.2%) vs. 10/175 (5.7%), P = 0.797]. Additional subgroup analysis revealed no difference in the frequency of antibiotic-associated rashes regardless of the presence or absence of high EBV loads. CONCLUSIONS: In this study, ampicillin rash was not observed, and antibiotic-associated rash was not associated with concurrent EBV infection. Penicillin derivatives can be used safely, even in liver transplant recipients with persistent asymptomatic EBV infection.

New Constraint on Primordial Lepton Flavor Asymmetries.

A chiral chemical potential present in the early Universe can source helical hypermagnetic fields through the chiral plasma instability. If these hypermagnetic fields survive until the electroweak phase transition, they source a contribution to the baryon asymmetry of the Universe. In this Letter, we demonstrate that lepton flavor asymmetries above |µ|/T∼9×10^{-3} trigger this mechanism even for vanishing total lepton number. This excludes the possibility of such large lepton flavor asymmetries present at temperatures above 10^{6} GeV, setting a constraint which is about 2 orders of magnitude stronger than the current CMB and BBN limits.

Distinct association between chronic Epstein-Barr virus infection and T cell compartments from pediatric heart, kidney, and liver transplant recipients.

Chronic Epstein-Barr virus (EBV) infection after pediatric organ transplantation (Tx) accounts for significant morbidity and mortality. The risk of complications, such as posttransplant lymphoproliferative disorders, in high viral load (HVL) carriers is the highest in heart Tx recipients. However, the immunologic signatures of such a risk have been insufficiently defined. Here, we assessed the phenotypic, functional, and transcriptomic profiles of peripheral blood CD8+/CD4+ T cells, including EBV-specific T cells, in 77 pediatric heart, kidney, and liver Tx recipients and established the relationship between memory differentiation and progression toward exhaustion. Unlike kidney and liver HVL carriers, heart HVL carriers displayed distinct CD8+ T cells with (1) up-regulation of interleukin-21R, (2) decreased naive phenotype and altered memory differentiation, (3) accumulation of terminally exhausted (TEX PD-1+T-bet-Eomes+) and decrease of functional precursors of exhausted (TPEX PD-1intT-bet+) effector subsets, and (4) transcriptomic signatures supporting the phenotypic changes. In addition, CD4+ T cells from heart HVL carriers displayed similar changes in naive and memory subsets, elevated Th1 follicular helper cells, and plasma interleukin-21, suggesting an alternative inflammatory mechanism that governs T cell responses in heart Tx recipients. These results may explain the different incidences of EBV complications and may help improve the risk stratification and clinical management of different types of Tx recipients.

Etiology of Severe Acute Hepatitis in a Pediatric Transplant Center in Japan.

The proportion of pediatric cases with severe acute hepatitis of unknown etiology in the coronavirus disease 2019 era was higher than that in the pre-coronavirus disease 2019 era in Japan's largest pediatric transplant center. Further research and monitoring are essential.

Usefulness of lysophosphatidylcholine measurement in the cerebrospinal fluid for differential diagnosis of neuropathic pain: Possible introduction into clinical laboratory testing.

BACKGROUND: The differential diagnosis of neuropathic pain, especially discrimination between neuropathic pain caused by spinal canal stenosis (SCS) and neuropathic pain associated with causes other than SCS, is sometimes difficult; however, it is important for surgical application. METHODS: We established a reliable method for measuring lysophosphatidylcholine (LPC), a precursor of lysophosphatidic acids which are known as being pain initiators, using a liquid chromatography-tandem mass spectrometry method, and measured the LPC concentrations in the cerebrospinal fluid (CSF) in patients with SCS (SCS group; n = 76), patients with neuropathic pain caused by non-SCS diseases (Others group; n = 49), and control subjects without pain (control group; n = 92). RESULTS: Both within-run and between-run CV(%) were almost < 10 %, suggesting an enough performance for clinical introduction. The CSF concentrations of LPC (16:0) and LPC (18:0) were higher in the SCS group than those in the Control or Others group; the concentrations of LPC (18:1), LPC (18:2), LPC (20:4), LPC (22:6) levels were higher in the SCS group than those in the control or others group, but they were also higher in the Others group than those in the control group. The areas under the curve in the ROC curve analyses of LPC (18:1) for discriminating between the SCS and control groups, others and control groups, and SCS and others groups were 0.994, 0.860, and 0.869, respectively. CONCLUSIONS: LPC measurement in the CSF is useful for the differential diagnosis of neuropathic pain, especially for surgical decision-making, which is expected for clinical introduction.

Successful pediatric liver transplantation case with a positive SARS-CoV-2 test at the time of transplant.

AIM: We report a successful liver transplantation (LT) in a child with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. CASE PRESENTATION: A 3-year-old female patient with decompensated cirrhosis due to Alagille syndrome underwent a split LT with a left lateral segment graft. She had a history of SARS-CoV-2 infection 4 months before LT. She was exposed to SARS-CoV-2 after the decision for organ acceptance. We repeatedly confirmed the negative SARS-CoV-2 test by polymerase chain reaction (PCR) before LT. Liver transplantation was carried out in the negative pressure operational theater with full airborne, droplet, and contact precautions as the patient was considered to be within the incubation period of SARS-CoV-2. The SARS-CoV-2 PCR test became positive in the nasopharyngeal swab specimen at the operation. Remdesivir, the antiviral treatment, was held off due to potential hepatotoxicity and no exacerbation of COVID-19. She received tacrolimus and low-dose steroids per protocol. She remained SARS-CoV-2 positive on postoperative days (PODs) 1, 2, and 5. The presence of antibodies for SARS-CoV-2 at LT was confirmed later. On POD 53, she was discharged without any symptomatic infection. CONCLUSION: This case demonstrated that a positive SARS-CoV-2 result was not an absolute contraindication for a life-saving LT. Liver transplantation could be safely performed in a pediatric patient with asymptomatic COVID-19 and S-immunoglobulin G antibodies for SARS-CoV-2.

Pediatric Infectious Diseases Related to Transplantation: Insights From Japan.

Infectious diseases after transplantation account for significant morbidity and mortality in children undergoing transplantation; the importance of pediatric transplant infectious disease (TID) specialists has therefore been recognized. Although tremendous advancement continues in transplantation medicine, pediatric-specific data and evidence are limited. In Japan, the majority of TIDs had not been managed by infectious disease specialists because pediatric infectious diseases have not been recognized as a solo subspecialty until recently in Japan. However, in the last decade, there was a new movement for pediatric TID in Japan; some pediatric infectious disease specialists trained outside Japan have been playing an important role in managing pediatric TID in a few academic and pediatric institutions. In this review article, we introduce the current status of infectious complications related to pediatric hematopoietic cell and solid organ transplantation, highlighting currently available local evidence, common practice and issues in the field of pediatric TID in Japan.

Early Detection of Epstein-Barr Virus as a Risk Factor for Chronic High Epstein-Barr Viral Load Carriage at a Living-donor-dominant Pediatric Liver Transplantation Center.

BACKGROUND: Epstein-Barr virus (EBV) infection and posttransplant lymphoproliferative disorders (PTLDs) after pediatric liver transplantation (LT) account for significant morbidity and mortality. Knowledge of EBV kinetics, epidemiology, and outcomes among pediatric living-donor LT cases is largely lacking. This study aims to provide clinical information related to EBV infection, chronic high EBV load (CHL) carriage, and PTLD at a living-donor-dominant pediatric LT center. METHODS: A total of 5827 EBV load measurements from 394 LT recipients fulfilling inclusion criteria and their clinical data were analyzed. EBV loads >1000 copies/µg DNA (742 IU/µg DNA) were considered "high," and CHL was defined by persistence >6 mo. RESULTS: The highlighted results were as follows: (1) 94% of recipients underwent living-donor LT; (2) 80% of EBV seronegative recipients developed first EBV infection <2 y post-LT, and their EBV loads were consistently higher than those of seropositive recipients within <3 y post-LT but did not differ thereafter; (3) 61 (15%) recipients met CHL criteria, but none developed PTLD; (4) age <5 y, cytomegalovirus seronegative donors, and early development of EBV DNAemia <6 mo post-LT were independent risk factors for CHL; (5) the incidence of rejections after 1-y post-LT was comparably low among CHL carriers whose immunosuppression was minimized. CONCLUSIONS: Early detection of EBV following LT and CMV seronegative donors would facilitate risk stratification to prevent PTLD while titrating immunosuppression among pediatric LT recipients.

Comparison of clinical characteristics of COVID-19 in pregnant women between the Delta and Omicron variants of concern predominant periods.

BACKGROUND: Information regarding effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant strains on clinical manifestations and outcomes of coronavirus disease 2019 (COVID-19) in pregnant women is limited. METHODS: A retrospective observational study was conducted using the data from the nationwide COVID-19 registry in Japan. We identified pregnant patients with symptomatic COVID-19 hospitalized during the study period. The Delta and Omicron variants of concern (VOC) predominant periods were defined as August 1 to December 31, 2021 and January 1 to May 31, 2022, respectively. Clinical characteristics were compared between the patients in the Delta and Omicron VOC periods. In addition, logistic regression analysis was performed to identify risk factors for developing moderate-to-severe COVID-19. RESULTS: During the study period, 310 symptomatic COVID-19 cases of pregnant women were identified; 111 and 199 patients were hospitalized during the Delta and Omicron VOC periods, respectively. Runny nose and sore throat were more common, and fatigue, dysgeusia, and olfactory dysfunction were less common manifestations observed in the Omicron VOC period. In the multivariable logistic regression analysis, onset during the later stage of pregnancy (OR: 2.08 [1.24-3.71]) and onset during the Delta VOC period (OR: 2.25 [1.08-4.90]) were independently associated with moderate-to-severe COVID-19, whereas two doses of SARS-CoV-2 vaccine were protective against developing moderate-to-severe COVID-19 (OR: 0.34 [0.13-0.84]). CONCLUSIONS: Clinical manifestations of COVID-19 in pregnant women differed between the Delta and Omicron VOC periods. SARS-CoV-2 vaccination was still effective in preventing severe COVID-19 throughout the Delta and Omicron VOC periods.

Safety of and antibody response to the BNT162b2 COVID-19 vaccine in adolescents and young adults with underlying disease.

BACKGROUND: Data are limited regarding the safety of and antibody response to the BNT162b2 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger ribonucleic acid vaccine in adolescents and young adults with underlying disease. METHODS: This prospective observational study enrolled patients age 12-25 years with chronic underlying disease who received 2 doses of BNT162b2. A 18-item questionnaire was used to assess adverse events within 7 days post-vaccination, and data regarding severe adverse events were collected from electronic medical records. An antibody titer for the receptor-binding domain of the spike protein in SARS-CoV-2 was used to assess antibody response after the second vaccine dose. RESULTS: Study participants were 429 patients (241 [56.2%] age 12-15 years; 188 [43.8%] age 16-25 years). The most common underlying diseases were genetic or chromosomal abnormalities and/or congenital anomalies, followed by endocrine or metabolic diseases; 32% of participants were immunocompromised. Severe adverse events were observed after the second dose in 1 (0.4%) patient age 12-15 years and in 2 (1.1%) patients age 16-25 years; all patients recovered. Seropositivity after the second vaccine dose was 99.0%. The geometric mean antibody titer was higher in patients age 12-15 years versus 16-25 years (1603.3 [1321.8-1944.7] U/mL vs. 949.4 [744.2-1211.0] U/mL). Compared with immunocompetent patients, immunocompromised patients had a lower antibody titer (2106.8 [1917.5-2314.7] U/mL vs. 467.9 [324.4-674.8] U/mL). CONCLUSIONS: Vaccination with BNT162b2 was acceptably safe and immunogenic for adolescents and young adults with underlying disease.

Elucidating Differences in Early-Stage Centrosome Amplification in Primary and Immortalized Mouse Cells.

The centrosome is involved in cytoplasmic microtubule organization during interphase and in mitotic spindle assembly during cell division. Centrosome amplification (abnormal proliferation of centrosome number) has been observed in several types of cancer and in precancerous conditions. Therefore, it is important to elucidate the mechanism of centrosome amplification in order to understand the early stage of carcinogenesis. Primary cells could be used to better understand the early stage of carcinogenesis rather than immortalized cells, which tend to have various genetic and epigenetic changes. Previously, we demonstrated that a poly(ADP-ribose) polymerase (PARP) inhibitor, 3-aminobenzamide (3AB), which is known to be nontoxic and nonmutagenic, could induce centrosome amplification and chromosomal aneuploidy in CHO-K1 cells. In this study, we compared primary mouse embryonic fibroblasts (MEF) and immortalized MEF using 3AB. Although centrosome amplification was induced with 3AB treatment in immortalized MEF, a more potent PARP inhibitor, AG14361, was required for primary MEF. However, after centrosome amplification, neither 3AB in immortalized MEF nor AG14361 in primary MEF caused chromosomal aneuploidy, suggesting that further genetic and/or epigenetic change(s) are required to exhibit aneuploidy. The DNA-damaging agents doxorubicin and γ-irradiation can cause cancer and centrosome amplification in experimental animals. Although doxorubicin and γ-irradiation induced centrosome amplification and led to decreased p27Kip protein levels in immortalized MEF and primary MEF, the phosphorylation ratio of nucleophosmin (Thr199) increased in immortalized MEF, whereas it decreased in primary MEF. These results suggest that there exists a yet unidentified pathway, different from the nucleophosmin phosphorylation pathway, which can cause centrosome amplification in primary MEF.

Development and multicenter validation of an LC-MS-based bioanalytical method for antisense therapeutics.

Background: Many bioanalytical methods for antisense oligonucleotides (ASOs) using LC-MS have been reported. However, no data have been available on the reproducibility and robustness of a single bioanalytical method for ASOs. As such, in the current study, we evaluated the reproducibility and robustness of LC-MS-based bioanalytical methods for ASOs in multiple laboratories. Methods/Results: Seven independent laboratories were included in this study. Mipomersen was measured by ion-pairing LC-MS (IP-LC-MS) as a model ASO using different LC-MS. The validation results of calibration curve, accuracy, precision and selectivity met the criteria of conventional bioanalytical method validation guidelines using LC/GC-MS for drugs in all laboratories. Meanwhile, carryover (>20%) was detected in three laboratories. Conclusion: We first demonstrated the multicenter-validated IP-LC-MS bioanalytical method for ASOs. Our data showed that the method was sensitive, robust and reproducible. However, the occurrence of carryover should be carefully monitored in its future application.

Fast and Ultrasensitive Glycoform Analysis by Supercritical Fluid Chromatography-Tandem Mass Spectrometry.

The glycoform of a therapeutic monoclonal antibody (mAb) has a significant impact on its effector function as well as its safety and pharmacokinetics. Glycoform heterogeneity is influenced by various factors, including the producing cells and cell culture processes. Therefore, accurate glycoform characterization is essential for drug design, process optimization, manufacturing, and quality control of therapeutic mAbs. In this study, we developed a fast, quantitative, and highly sensitive analytical platform for glycan profiling by supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS) and applied the technique to the glycan structural analysis of mAbs. To achieve both the highest sensitivity and the most comprehensive glycan profiling, we integrated our energy-resolved oxonium ion monitoring (Erexim) method with SFC-MS to construct a new SFC-Erexim technology. An 8 min analysis of bevacizumab, nivolumab, ramucirumab, rituximab, and trastuzumab by SFC-Erexim detected a total of 102 glycoforms, with a detection limit of 5 attomoles. The dynamic range of glycan abundance was over 6 orders of magnitude for bevacizumab analysis by SFC-Erexim compared to 3 orders of magnitude for conventional fluorescence HPLC analysis. This method revealed the glycan profile characteristics and lot-to-lot heterogeneity of various therapeutic mAbs. We were also able to detect a series of structural variations in pharmacologically important glycan structures. The SFC-MS-based glycoform profiling method will provide an ideal platform for the in-depth analysis of precise glycan structure and abundance.

Acute Antibody-mediated Rejection Coexisting With T Cell-mediated Rejection in Pediatric ABO-incompatible Transplantation.

The management and outcome of ABO-incompatible (ABO-I) liver transplantation (LT) has been improving over the past few decades. Recently, the introduction of a pathological evaluation of acute antibody-mediated rejection (AMR) for liver allograft has provided a new recognition of allograft rejection in LT. Methods: One hundred and one pediatric ABO-I LTs performed in our institute were retrospectively analyzed. We assessed the clinical manifestations, diagnosis, and treatment of acute AMR, focusing on the recipient age and pathological findings. Results: Twelve cases (11.9%) of acute AMR related to ABO-I were observed. Nine cases developed mixed T cell-mediated rejection (TCMR)/AMR. These consisted of 6 patients in the younger age group for whom the preconditioning treatment was not indicated and 4 patients in the older age group to whom rituximab was administered as planned. Two patients in the older age group to whom preoperative rituximab was not administered as planned developed isolated AMR. Acute AMR in the older group required plasma exchange for treatment, regardless of the coexistence of TCMR. In contrast, those in the younger group were successfully treated by intravenous methylprednisolone pulse and intravenous immunoglobulin without plasma exchange, accounting for mild immune reaction. Conclusions: Acute ABO-I AMR can develop simultaneously with TCMR, even in young patients with a compromised humoral immune response following ABO-I LT. Establishing the accurate diagnosis of AMR with a pathological examination, including component 4d staining, is crucial for optimizing treatment.