Assays For Epstein-Barr Virus Research Articles

Performance evaluation of the high-throughput quantitative Alinity m Epstein-Barr virus assay.

Epstein-Barr virus (EBV) infection and reactivation are associated with increased risk for post-transplant lymphoproliferative disorders (PTLD) in transplant recipients with the development of PTLD occurring predominantly within a year of transplant. Quantitative PCR for EBV is used to monitor the viral load of EBV with a negative result as a good negative predictor of PTLD. Nucleic acid amplification tests (NAATs) with high sensitivity and specificity are available on fully automated high-throughput instruments to provide accurate quantitation and improve test result turn-around time. This study evaluates the analytical and clinical performance of one such NAAT, the Alinity m EBV assay.

Development of a Rapid Epstein-Barr Virus Detection System Based on Recombinase Polymerase Amplification and a Lateral Flow Assay.

The quality of cellular products used in biological research can directly impact the ability to obtain accurate results. Epstein-Barr virus (EBV) is a latent virus that spreads extensively worldwide, and cell lines used in experiments may carry EBV and pose an infection risk. The presence of EBV in a single cell line can contaminate other cell lines used in the same laboratory, affecting experimental results. We developed three EBV detection systems: (1) a polymerase chain reaction (PCR)-based detection system, (2) a recombinase polymerase amplification (RPA)-based detection system, and (3) a combined RPA-lateral flow assay (LFA) detection system. The minimum EBV detection limits were 1 × 103 copy numbers for the RPA-based and RPA-LFA systems and 1 × 104 copy numbers for the PCR-based system. Both the PCR and RPA detection systems were applied to 192 cell lines, and the results were consistent with those obtained by the EBV assay methods specified in the pharmaceutical industry standards of the People's Republic of China. A total of 10 EBV-positive cell lines were identified. The combined RPA-LFA system is simple to operate, allowing for rapid result visualization. This system can be implemented in laboratories and cell banks as part of a daily quality control strategy to ensure cell quality and experimental safety and may represent a potential new technique for the rapid detection of EBV in clinical samples.

Multi-site performance evaluation of the Alinity m Molecular assay for quantifying Epstein-Barr virus DNA in plasma samples.

Detection and monitoring of acute infection or reactivation of Epstein-Barr virus (EBV) are critical for treatment decision-making and to reduce the risk of EBV-related malignancies and other associated diseases in immunocompromised individuals. The analytical and clinical performance of the Alinity m EBV assay was evaluated at two independent study sites; analytical performance was assessed by evaluating precision with a commercially available 5-member EBV verification panel, while the clinical performance of the Alinity m EBV assay was compared to the RealTime EBV assay and a laboratory-developed test (LDT) as the routine test of record (TOR). Analytical analysis demonstrated standard deviation (SD) between 0.08 and 0.13 Log IU/mL. A total of 300 remnant plasma specimens were retested with the Alinity m EBV assay, and results were compared to those of the TOR at the respective study sites (n = 148 with the RealTime EBV assay and n = 152 with the LDT EBV assay). Agreement between Alinity m EBV and RealTime EBV or LDT EBV assays had kappa values of 0.88 and 0.84, respectively, with correlation coefficients r of 0.956 and 0.912, while the corresponding observed mean bias was -0.02 and -0.19 Log IU/mL. The Alinity m EBV assay had a short median onboard turnaround time of 2:40 h. Thus, the Alinity m system can shorten the time to results and, therefore, to therapy.

Evaluation of a Quantitative Dual-Target EBV DNA Test on a Fully Automated Molecular Testing System.

The measurement of Epstein-Barr virus (EBV) deoxyribonucleic acid (DNA) is key to diagnosing and managing EBV-associated complications in transplant recipients. The performance of the new Conformité Européenne (CE) and Food and Drug Administration (FDA)-cleared quantitative Roche cobas EBV real-time PCR assay was determined by using EDTA-plasma dilution panels and clinical samples that were spiked with either the World Health Organization's EBV international standard or high-titer EBV lambda stock. Correlation with the Abbott Realtime EBV assay was assessed in clinical specimens and conducted at two independent laboratories. An in silico analysis revealed that the dual-target test (EBNA1 and BMRF2) was 100% inclusive for the known diversity of EBV. The overall limit of detection (LoD) was 16.6 IU/mL for genotype 1 (GT1). GT2 LoD was verified at 18.8 IU/mL. The linear ranges were from 1.40 × 101 to 2.30 × 108 IU/mL and from 2.97 × 101 to 9.90 × 107 IU/mL for GT1 and GT2, respectively. Accuracy was confirmed across the linear range (mean difference not exceeding ±0.18 log10). Precision was not influenced by the factors analyzed (standard deviation of 0.02 to 0.17 log10), including the presence of potentially interfering endogenous or exogenous substances. Plasma samples were stable under several conditions (variable time points, storage, and freeze/thaw cycles). In clinical EBV DNA-positive samples, correlation between the cobas EBV test and the comparator was high (n = 126 valid results; R2 = 0.96) with a 0.1 mean log10 titer difference. The cobas EBV test is an accurate, sensitive, specific, and reproducible assay for the detection of EBV DNAemia in plasma. In general, high levels of automation and calibration to the international standard will lead to improvements in the harmonization of quantitative EBV DNA test results across laboratories.

A Systematic Review of Epstein-Barr Virus Antibodies as Clinical Biomarkers in Multiple Sclerosis (P1-3.007)

<h3>Objective:</h3> To systematically review Epstein-Barr Virus (EBV) titers as prognostic biomarkers in MS. <h3>Background:</h3> EBV is a necessary but insufficient factor in the pathophysiology of multiple sclerosis (MS). EBV antibodies to the nuclear antigen (EBNA1) and viral capsid antigen (VCA) rise rapidly prior to disease manifestations, and their absence could be used clinically given a high negative predictive value. It is unclear whether EBV titers act as prognostic, monitoring, or pharmacodynamic/response biomarkers. Significant literature on this topic exists but has not been synthesized. We hypothesized that EBV titers against the nuclear (EBNA1) and capsid (VCA) antigens are potential prognostic and monitoring biomarkers in MS, and that the patient population, MS clinical phenotype, and EBV assay method may play important roles in explaining variability among study outcomes. <h3>Design/Methods:</h3> We performed a systemic query in PubMed and EMBASE from inception to April 1, 2022. After removal of duplicates, records were screened by abstract. Remaining full text articles were reviewed. Clinical and MRI data were extracted from full text articles for comparison and synthesis. <h3>Results:</h3> Searches yielded 696 unique results, of which 285 were reviewed in full and 35 met criteria for data extraction. Heterogeneity in sample population, clinical outcome measures, assay methods and statistical analyses precluded a meta-analysis. EBV titers were not consistently associated with clinical disease markers including conversion from CIS to RRMS, neurological disability, or disease phenotype. Data from multiple studies show that titers may temporarily reflect inflammatory disease activity assessed by relapse or MRI lesions, and decrease with certain disease modifying therapies. <h3>Conclusions:</h3> Heterogeneous methodology limited generalization and meta-analysis. EBV titers are unlikely to represent prognostic biomarkers in MS. The areas of highest promise relate to diagnostic exclusion and pharmacodynamic/disease response. The use of EBV titers as biomarkers in clinical practice remains additionally limited by a lack of methodological precision, reliability, and validation. <b>Disclosure:</b> Dr. Bose has nothing to disclose. Dr. Khalighinejad has nothing to disclose. Dr. Hemond has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for VIVIO Health. Dr. Hemond has stock in VIVIO Health. The institution of Dr. Hemond has received research support from Consorium of Multiple Sclerosis Centers. The institution of Dr. Hemond has received research support from National Multiple Sclerosis Society. The institution of Dr. Hemond has received research support from National Center for Advancing Translational Sciences, National Institutes of Health. The institution of Dr. Hemond has received research support from University of Massachusetts Memorial Medical Center. The institution of Dr. Hemond has received research support from National Institute Of Neurological Disorders And Stroke of the National Institutes of Health. Dr. Hemond has received personal compensation in the range of $0-$499 for serving as a Member of Data Safety and Monitoring Board with National Institute Of Neurological Disorders And Stroke of the National Institutes of Health.

Comparison of four commercial EBV DNA quantitative tests to a new test at an early stage of development.

Regular screening for Epstein-Barr virus (EBV) DNA using quantitative RT-PCR is recommended for early intervention in at-risk patients. Harmonization of quantitative RT-PCR assays is critical to avoid misinterpretation of results. Here, we compare quantitative results of the cobas® EBV assay to four commercial RT-qPCR assays. The cobas EBV, EBV R-Gene, artus EBV RG PCR, RealStar EBV PCR kit 2.0 and Abbott EBV RealTime assays were compared for analytic performance using a 10-fold dilution series of EBV reference material, normalized to the WHO standard. For clinical performance, their quantitative results were compared using anonymized, leftover EBV-DNA-positive EDTA plasma samples. For analytic accuracy, the cobas EBV deviated -0.0097 log10 from target values. The other tests showed deviations between 0.0037 and -0.12 log10. For clinical performance, accuracy and linearity of cobas EBV data from both study sites were excellent. Bland-Altman bias and Deming regression analyses showed statistical correlation for cobas EBV to both EBV R-Gene and Abbott RealTime assays but an offset of cobas EBV to artus EBV RG PCR and RealStar EBV PCR kit 2.0. The cobas EBV showed the closest correlation to the reference material, followed closely by EBV R-Gene and Abbott EBV RealTime. Values obtained are stated in IU/mL, facilitating comparison across testing sites and potentially improving utilization of guidelines for diagnosis, monitoring, and treatment of patients.

Analytical evaluation of the cobas® 6800 system for the detection and quantification of BK Virus (BKV) and Epstein Barr Virus (EBV) at a US solid organ and hematopoietic stem cell transplant center

The cobas® EBV and BKV assays are the first FDA-approved, quantitative assays for monitoring posttransplant reactivation of these viruses. In this study, we assessed performance of the fully-automated cobas® assays, compared with Diasorin Molecular ASR, our laboratory developed test, and demonstrated a strong interassay correlation for BK and EBV monitoring.

Methylome Analysis of Epstein-Barr Virus with Nanopore Sequencing Reveals Viral State Dynamics

Epstein Barr Virus (EBV) is a gammaherpesvirus responsible for a broad spectrum of human diseases, including hematologic malignancies and autoimmune disorders. EBV maintains lifelong infection by entering an endosomal state of latency inside its host cell. In response to external stimuli EBV undergoes lytic activation, resulting in vast gene expression changes, DNA replication, and eventually release of infectious viral particles. DNA methylation of the EBV genome is essential to regulating its life cycle. Both lytic and latent life stages are key determinants of EBV-driven disease, but current clinical assays for EBV are limited to detecting the presence of EBV and do not provide important information on EBV lytic state. Thus, making clinical decisions based on EBV detection alone has remained challenging. To address these limitations, we have developed an EBV analysis pipeline utilizing nanopore sequencing from amplification-free, native DNA that directly interrogates CpG dinucleotide DNA methylation on the EBV genome. Our workflow generates highly accurate EBV methylation calls for the majority of CpGs across the EBV genome. We also deployed a quantitative mass-spectrometry-based methylation assay (EpiTYPER) to validate our data and provide broader analysis of a representative subset of methylation sites (n=123 methylation sites from n=25 EBV loci). To initially investigate the relationship between locus-specific EBV DNA methylation and EBV gene expression, we compared DNA methylation and RNA sequencing profiles in EBV-positive cell lines (n=7). We correlated global EBV DNA methylation levels and the overall patterns of latent versus lytic EBV gene expression. We found that average methylation levels are related to the ratio of latent versus lytic gene expression, establishing nanopore-derived DNA methylation as a method to quantify latent and lytic states in a given sample. We next shifted our approach to bin nanopore reads based on the average methylation of all CpGs per read, hypothesizing that latent/lytic viral states derive from distinct subpopulations of EBV endosomes that contain methylated versus unmethylated DNA. We uncovered widespread co-occurrence of high and low methylated viral DNA in cell lines, indicating that EBV methylation states exist in defined subfractions with either present or absent DNA methylation. In cell models of latent EBV infection (Akata, Kem, MEC1, Mutu, Rael) this approach showed that methylation states dynamically responded to lytic induction and selective pressure via antiviral treatment with ganciclovir. Of note, we observed a shift in methylation without the appearance of partially methylated DNA, indicating that EBV lytic activation/replication is associated with the appearance of unmethylated EBV DNA, and not gradual demethylation of endosomes in the latent viral state. Finally, we aimed to obtain measurements of overall EBV status in patients, using nanopore sequencing of cell-free DNA (cfDNA) obtained from patient plasma. We analyzed patients diagnosed with different EBV-positive diseases from The Ohio State University Medical Center, including n=3 patients with lymphomas (Burkitt, plasmablastic and diffuse large B cell lymphoma) and n=2 patients with post-transplant lymphoproliferative disorder (PTLD). The patient samples with lymphoma displayed a near uniformly high methylation profile, with little evidence of unmethylated DNA/lytic replication. One of the PTLD patients analyzed showed a distinct bi-modal distribution of per read EBV methylation values, indicating the presence of lytic replication in a significant proportion of cells. In conclusion, nanopore sequencing analysis of methylated versus unmethylated EBV DNA subfractions is a quantitative method for determining viral states. In patient samples, nanopore sequencing revealed methylation heterogeneity in cfDNA and may be a useful advancement compared to standard clinical EBV detection. Quantifying the relative ratio of latent versus lytic virus in a liquid biopsy sample could be used to guide therapy selection for patients displaying EBV-positivity. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Evaluation of the sample-to-result, random access NeuMoDx platform for viral load testing of Cytomegalovirus and Epstein Barr virus in clinical specimens

BackgroundThe detection and follow up of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) viral loads (VL) are crucial in the management of immunocompromised patients. Recently, molecular CE-IVD assays for detection and quantification of CMV and EBV have been launched for use on the random-access and sample-to-result NeuMoDx 96 and 288 platforms (Qiagen). ObjectiveEvaluating the qualitative and quantitative performance of the NeuMoDx CMV and EBV assays in clinical specimens compared to a lab developed tests (LDT) and the CE-IVD assays on the Abbott m2000 system. MethodBoth a prospective and a retrospective panel, compiled of non-detectable (ND), non-quantifiable (NQ) and quantifiable VLs in plasma samples have been evaluated for both CMV and EBV: NeuMoDx versus LDT and NeuMoDx versus Abbott m2000. Quantitative agreement was determined for samples with a quantifiable VL on both systems. ResultsQualitative and quantitative agreement between the NeuMoDx and LUMC's LDT CMV assays was 88%. Qualitative agreement between the NeuMoDx and Abbott m2000 CMV assays was 92% and quantitative agreement was 87%. Qualitative and quantitative agreement between the NeuMoDx and the LDT EBV assays was 87%. Qualitative agreement between the NeuMoDx and Abbott m2000 EBV assays was 91% and quantitative agreement was 0%. ConclusionThese data show that the NeuMoDx assays are suitable for both detection and quantification of CMV and EBV in a medium- to high throughput diagnostic setting, but that differences in sensitivity and quantification (for EBV, NeuMoDx versus Abbott m2000) warrant an extensive transition period when using the respective assays for following VL in patient samples.

Automated quantification of Epstein-Barr virus in whole blood for post-transplant lymphoproliferative disorders monitoring

BackgroundStandardized and sensitive assays for Epstein Barr Virus (EBV) are needed to define universal cutoff for treatment initiation in allogeneic hematopoietic stem cells transplant recipients. In a context of accreditation and the availability of EBV international standard, we evaluated the Abbott RealTime EBV (RT) assay for EBV quantification in whole blood.MethodsThe RT assay was compared on 282 prospective clinical samples with the Artus EBV PCR Kit V1 assay (V1) and we analyzed the kinetics of EBV load in 11 patients receiving rituximab treatment.ResultsThe estimated limit of detection was 88 IU/mL. The assay was linear (r2 = 0.9974) in the range of all samples tested (100 to 1,000,000 IU/mL). Intra-assay coefficients of variation (CV) ranged between 0.35 and 1.35%, and inter-assay CV between 3.40 and 4.5%. On samples above the limit of quantification, the two assays were strongly correlated. EBV RT values were on average 0.30 log10 IU/mL lower than those measured with the V1 assay. In patients treated with rituximab, the RT assay remained positive in 5 patients at the time it dropped below undetectable levels with the V1 assay.ConclusionsIn conclusion, the RT assay is a reliable assay for EBV load in whole blood. Its sensitivity will enable to estimate the kinetics of EBV load and the impact of treatments to control EBV reactivations.

Evaluation of the Abbott RealTime quantitative CMV and EBV assays using the maxCycle protocol in a laboratory automation context

Real-time PCR are often used for the diagnosis and monitoring of Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections in susceptible populations. In this context, we evaluated the analytical performances of the Abbott RealTime CMV/EBV maxCycle protocol automated on the m2000 platform (Abbott). It was compared to our routinely-used procedure consisting of a NucleoMag® DNA extraction automated on a STARlet platform followed by manually processed CMV and EBV quantitative real-time PCR (Diagenode). In this study, we showed that both EBV assays exhibited a similar sensitivity but with a better precision for the EBV Abbott RealTime assay. For the CMV performances, the Abbott assay was more sensitive and more precise than our routine method. The use of WHO International Standards also indicated a slight underestimation of the viral loads (−0.25 log10 IU/mL and −0.21 log10 IU/mL for CMV and EBV assays respectively) while these were rather overestimated with the Starlet/Diagenode method (0.48 log10 IU/mL and 0.19 log10 IU/mL for CMV and EBV assays respectively). These trends were confirmed using relevant whole-blood clinical samples and external quality controls. The workflows were also compared and we highlighted a significant technician hands-on time reduction (−63%) using the Abbott CMV/EBV maxCycle automated protocol.

Evaluation of the new Abbott Real-Time EBV assay: fully automated quantification of EBV in whole blood by targeting BLLF1

The accurate measurement of the Epstein–Barr virus (EBV) DNA level in the blood is required for managing EBV-associated diseases. A new commercial Abbott Real-Time EBV assay, which targets the BLLF1 gene, was evaluated on 120 clinical whole blood samples and the Qnostics EBV analytical panel. The limit of detection of the assay was 48.9 IU/mL (95% confidence interval, 48.1–49.8 IU/mL). The assay was linear from 2 to 5 log10 IU/mL (R2 = 0.997). The within-run coefficients of variation (CVs) ranged from 1.68% to 4.75% and the between-run CVs ranged from 1.73% to 12.83% for samples with high, medium, and low viral loads. EBV DNA loads measured by Abbott EBV assay strongly correlated with the results quantified by another commercial Nanogen EBV Real-Time Alert Q-PCR assay (r = 0.879, P < 0.0001). The fully automated Abbott Real-Time EBV assay targeting BLLF1 reduced both hands-on time and turnaround time and demonstrated a reliable performance for EBV DNA quantification in whole blood.

Co-Infections by Double-Stranded DNA Viruses after Ex Vivo T Cell–Depleted, CD34+ Selected Hematopoietic Cell Transplantation

Recipients of ex vivo T cell–depleted (TCD) hematopoietic cell transplantation (HCT) are at risk of infection by double-stranded (ds) DNA viruses. We report rates of dsDNA viremia, end-organ disease (EOD), infection-related mortality, and overall survival (OS) in a contemporary cohort of adult TCD HCT recipients routinely monitored for cytomegalovirus (CMV), adenovirus (ADV), human herpesvirus 6 (HHV6), and Epstein-Barr virus (EBV). Healthcare utilization in the first 6 months post-HCT was compared between patients with dsDNA viremia versus no viremia. This was an observational study of adult patients with acute leukemia and myelodysplastic syndrome who received CD34+ selected, peripheral blood HCT at Memorial Sloan Kettering Cancer Center from March 2012 through December 2014. Patients were prospectively monitored by quantitative PCR assays for CMV, ADV, HHV6, and EBV in whole blood or plasma. The cumulative incidence of viremia(s) at day +180, EOD at 1 year, and OS at 1 year were estimated by the Kaplan-Meier method and compared by the log-rank test among patient with and without viremia/EOD. Standardized incidence ratios were used to compare overall length of hospital stay (LOS), number of readmissions after HCT, and length of readmissions through day +180. Of 156 patients, 96 (62%) were CMV recipient seropositive. Forty-two patients received grafts from matched related (27%), 86 from matched unrelated (55%), and 28 from mismatched (18%) donors. Overall, 132 patients (85%) had ≥1 viremia and 52 (33%) ≥2 viremias by day +180. The cumulative incidences for CMV, HHV6, ADV, and EBV viremia were 44%, 61%, 7%, and 16%, respectively, with median times of onset 28 days (interquartile range [IQR], 25 to 33), 33 days (IQR, 25 to 47), 60 days (IQR, 19 to 84), and 79 days (IQR, 54 to 106) post-HCT, respectively. Twenty-eight patients (18%) developed EOD by dsDNA viruses at 1 year post-HCT. Treatment for CMV accounted for 91% total antiviral treatment-days. Compared with patients with no viremia, patients with CMV viremia, HHV6 viremia, or ≥2 viremias experienced longer LOS (P < .001) and a higher number of readmissions (P < .001) by day +180. OS rate at 1 year was 79% and was similar between patients with or without dsDNA viremias. EOD was associated with lower 1-year OS rates (63.4%) versus without EOD (81.1%) (P = .02). Of 33 patients who died, 10 died due to infection, and 7 of these infection-related deaths were due to dsDNA viruses. Viremia by dsDNA viruses occurred in 85% of TCD HCT recipients by day +100 and 33% of patients experienced ≥2 viremias by day +180. CMV accounted for most antiviral use. CMV, HHV6, or ≥2 viremias were associated with more readmissions and longer LOS. One year OS rate was 78%. EOD by dsDNA viruses was associated with decreased 1-year OS. Infections by dsDNA viruses pose a substantial burden after TCD HCT.

Current State of PCR-Based Epstein-Barr Virus DNA Testing for Nasopharyngeal Cancer.

Clinical studies have shown plasma Epstein-Barr virus (EBV) DNA level to be an independent prognostic biomarker for nasopharyngeal carcinoma (NPC). However, the proportion of NPC patients whose tumors are associated with EBV vary with geographic location, and there are a variety of assays for plasma EBV. To develop the level of evidence needed to demonstrate the clinical utility of plasma EBV DNA detection for NPC patients and encourage widespread adoption of this biomarker test in clinical laboratories, validated harmonized assays are needed. In 2015, the National Cancer Institute (NCI) convened a Workshop on Harmonization of EBV Testing for Nasopharyngeal Cancer, where experts in head and neck oncology and laboratory medicine addressed the limitations of currently available polymerase chain reaction-based EBV DNA quantitation assays and discussed strategies for advancing the development of harmonized EBV DNA assays and their appropriate clinical use. This article presents the key recommendations to direct future efforts in assay harmonization and validation.

Comparison of the artus Epstein–Barr virus (EBV) PCR kit and the Abbott RealTime EBV assay for measuring plasma EBV DNA loads in allogeneic stem cell transplant recipients

The ability of the artus Epstein–Barr virus (EBV) PCR kit and the Abbott RealTime EBV PCR assay to detect and quantify plasma EBV DNAemia was compared. The agreement between these assays was 95.8%. The EBV DNA loads measured by the two assays significantly correlated (P=< 0.0001).

Commutability of the Epstein-Barr virus WHO international standard across two quantitative PCR methods.

The commutability of international reference standards is critical for ensuring quantitative agreement across different viral load assays. Here, we demonstrate the commutability of the Epstein-Barr virus (EBV) WHO international standard for the BamHI-W and artus EBV assays.

Comparative evaluation of the new ARCHITECT EBV assays considering different testing algorithms

In the current evaluation, Epstein-Barr virus (EBV) serology was performed on 1113 routine serum samples. Although the initial request for all samples from the general practitioner was EBV IgM testing, 80.9% were classified as past infections. The ARCHITECT® viral capsid antigen (VCA) IgM, VCA IgG, and EBV nuclear antigen (EBNA) 1 IgG assays showed good results for sensitivity and specificity, being 100.0%, 98.3%, and 100.0% and 99.9%, 95.4%, and 99.6%, respectively. Using an algorithm based on initial EBNA-1 IgG testing, followed by VCA IgG and IgM for samples that were not EBNA-1 IgG reactive, the number of tests per sample could be reduced to nearly 50% compared to parallel testing. The high sensitivity and specificity of the ARCHITECT® EBNA-1 IgG assay in combination with a low number of grayzone results are a precondition for the chosen test algorithm. Thus, the newly developed ARCHITECT® EBV panel is suitable for accurate and cost-efficient EBV serology in a routine clinical laboratory.

Incidence of posttransplantation lymphoproliferative disorder (PTLD) following allogeneic blood or marrow transplantation (alloBMT) using post-transplantation cyclophosphamide (PT-Cy) for graft-versus-host disease (GVHD) prophylaxis.

7009 Background: Immunosuppression to prevent graft rejection and GVHD is associated with an increased incidence of PTLD in the first year after alloBMT. AlloBMTs using partially HLA-mismatched or unrelated donor grafts, particularly when coupled with selective T-cell depletion approaches and/or anti-thymocyte globulin therapy, are associated with PTLD rates of 4-8%. The incidence of PTLD after umbilical cord blood alloBMT ranges from 2-7%. We evaluated the incidence of PTLD associated with the use of PT-Cy as GVHD prophylaxis at Johns Hopkins Hospital. Methods: After IRB approval, the Blood and Marrow Transplant Research database was queried for adult patients (age &gt; 18) who received PT-Cy as GVHD prophylaxis. Medical records from the first year after alloBMT, including clinical notes, pathology reports, and laboratory assays for Epstein-Barr virus (EBV), were reviewed. Results: From 2000-2011, 765 alloBMT patients received PT-Cy (50 mg/kg/day on days 3 and 4 after alloBMT) as GVHD prophylaxis. Of these, 734 patients had 1-year follow-up or death. In patients receiving myeloablative conditioning and HLA-matched grafts (n=289, 117 unrelated donors), PT-Cy was the sole GVHD prophylaxis. Other patients undergoing alloBMT received mycophenolate mofetil and tacrolimus in addition to PT-Cy. These included recipients of HLA-matched (n=63) or haploidentical (n=352) grafts who were conditioned with reduced intensity regimens, as well as recipients of HLA-haploidentical grafts who received myeloablative regimens (n=30). Forty-one patients with CD20(+) tumors received rituximab after alloBMT as part of a clinical protocol. There were no cases of PTLD. Conclusions: The absence of PTLD in this series, even among high-risk recipients of haploidentical or unrelated donor grafts, suggests that PT-Cy is less associated with PTLD than other GVHD prophylaxis strategies. We hypothesize that multiple mechanisms may account for the lack of PTLD with PT-Cy, including destruction of B cells that harbor EBV, sparing of EBV-specific memory T cells, and rapid immune reconstitution.

Development of multiplex serological assays to detect oncoviral infections

Serological markers of infection (antibodies or antigens) of viruses that cause cancer are most often detected using ELISA-based methodologies. In many cases, multiple markers of infection must be assessed to determine a final sero-status. Volume requirements and costs of reagents for single analyte ELISAs are high and studies which include multiple viruses can require milliliters of plasma, often not available from archived cohorts. Thus, we sought to develop a Luminex® bead-based customizable panel initially including Hepatitis B Virus (HBV), Hepatitis C Virus (HCV), Epstein-Barr Virus (EBV) and often the concomitant infection, Human Immunodeficiency Virus (HIV) to reduce sample volume requirements, overall cost and increase flexibility. Peptides, antigens and antibodies were sourced from multiple manufacturers and tested for suitability in this platform. Where necessary, suitable reagents were designed and produced in-house. The HCV assay multiplexes four HCV peptides designed to detect antibodies raised to HCV Core (2), HCV NS4, HCV NS5 gene regions. The HBV assay multiplexes a HBV early antigen peptide, a recombinant HBV core protein and either a recombinant HBV surface antigen or an antibody specific for HBV surface antigen to assess HBV infection. The EBV assay multiplexes peptides specific to viral capsid antigen, EBNA-1 and early antigen (Cyto-Barr, Zuidhorn, The Netherlands). HIV-1 assay development is ongoing and the list of antigens to be included in the assay has not been finalized. These assays can be run singly or with any combination (multi-plex) of the above listed targets. Each target has been independently validated using samples of known molecular and serological status to determine specificity (false positive versus false negative) and re-evaluated under multiplex conditions to confirm assay performance. In addition, where possible, samples were assayed on commercial testing platforms as well as our multiplex assay to assess concordance (94-99%). Dependent on the panel selected and the expected antibody titers in a particular population, plasma or serum volumes in the range of 10 µL to 125 µL per subject would be required to determine the HBV, HCV, EBV and/or HIV serostatus of a subject. This assay platform is inherently flexible and the benefits include amenability to expansion to include other oncogenic viruses as well as screening large epidemiological cohorts or smaller subsets of samples in an economical and high throughput manner.

Serological and virological investigation of the role of the herpesviruses EBV, CMV and HHV‐6 in post‐infective fatigue syndrome

Multiple previous studies have sought evidence for ongoing, active infection with, or reactivation of, Herpesviruses in patients with chronic fatigue syndrome (CFS), with conflicting results. This study aimed to clarify this by studying 20 patients enrolled in a well-characterized model of the onset and evolution of CFS, the prospective cohort of the Dubbo Infection Outcomes Study (DIOS). The patients selected for examination included five CFS patients with primary Epstein-Barr virus (EBV) infection; five CFS patients with acute viral infection not caused by EBV; and 10 matched controls with prompt resolution of primary EBV infection. Serum samples from three timepoints were assayed using a comprehensive range of serological assays for EBV, HHV-6, and CMV. Viral genomes were assessed using quantitative PCR assays. All patients were seropositive for HHV-6, and 10 were seropositive for CMV at infection baseline (five patients and five controls). Low titer CMV IgM antibodies were found at infection baseline in two of these cases and three control patients. HHV-6 IgG antibody titers were highest at infection baseline but did not differ between the CFS cases and the control patients. There were increases in EBV IgG VCA p18, EBNA-1 IgG, and EA IgG titers over time, but these did not differ between CFS cases and control patients. EBV and HHV6 DNA levels were at control levels in a minority of samples, and CMV was undetectable in all samples. These data do not support the hypothesis of ongoing or reactivated EBV, HHV-6, or CMV infection in the pathogenesis of CFS.