Quantitative analysis of Epstein-Barr virus load by using a real-time PCR assay

Polyclonal, newly derived T cells with low expression of inhibitory molecule PD-1 in tonsils define the phenotype of lymphocytes in children with Periodic Fever, Aphtous Stomatitis, Pharyngitis and Adenitis (PFAPA) syndrome

PURPOSE

PFAPA syndrome is a benign, recurrent inflammatory disease of childhood. Tonsillectomy is one of the therapeutic options with a yet unexplained biological mechanism. We tested whether specific lymphocyte subsets recruited from blood to human tonsils participate in PFAPA pathogenesis.

METHODS

Paired tonsils/peripheral blood (PB) samples were investigated (a) from children with PFAPA that successfully resolved after tonsillectomy (n=10) (b) from children with obstructive sleep apnoea syndrome as controls (n=10). The lymphocyte profiles were analysed using 8-colour flow cytometry, immunoglobulin (IGH) and T-cell receptor (TCR) gene rearrangements via PCR and next generation sequencing; a TREC/KREC analysis was performed using qPCR.

RESULTS

The PFAPA tonsils in the asymptomatic phase had a lower percentage of B-lymphocytes than controls; T-lymphocyte counts were significantly higher in PB. The percentages of cytotoxic CD8pos T-lymphocytes were approximately 2-fold higher in PFAPA tonsils; the transitional B cells and naïve stages of both the CD4pos and CD8pos T-lymphocytes with a low expression of PD-1 molecule and high numbers of TREC were also increased. With the exception of elevated plasmablasts, no other differences were significant in PB. The expression levels of CXCL10, CXCL9 and CCL19 genes were significantly higher in PFAPA tonsils. The IGH/TCR pattern showed no clonal/oligoclonal expansion. DNA from the Epstein-Barr virus, Human Herpervirus-6 or adenovirus was detected in 7 of 10 PFAPA tonsils but also in 7 of 9 controls.

CONCLUSIONS

Our findings suggest that the uninhibited, polyclonal response of newly derived lymphocytes participate in the pathogenesis of PFAPA. Because most of the observed changes were restricted to tonsils and were not present in PB, they partly explain the therapeutic success of tonsillectomy in PFAPA syndrome.

Immune-mediated neuropathy with Epstein-Barr virus-positive T-cell lymphoproliferative disease

A 47-year-old man with Epstein-Barr virus (EBV)-positive T/NK- cell lymphoproliferative disease (EBV-T/NK-LPD) developed acute-onset weakness. A nerve conduction study showed a conduction block in both the proximal and most distal segments. Although the patient's neuropathy transiently responded to intravenous immunoglobulin, it was progressive for at least 25 days until the start of prednisolone (PSL) administration, after which it remarkably improved. The neuropathy further improved after allogeneic bone marrow transplantation (BMT). The present patient's clinical course is not consistent with that of typical Guillain-Barré syndrome. This case suggests that EBV-T/NK-LPD can cause progressive immune-mediated neuropathy as a result of chronic EBV antigen presentation and can be treated with PSL and BMT.

Successful Immunosuppressive Therapy for Severe Infectious Mononucleosis in a Patient with Clonal Proliferation of EBV-infected CD8-positive Cells

A 30-year-old woman was diagnosed with severe infectious mononucleosis (IM). The Epstein-Barr virus (EBV) had infected both CD19- and CD8-positive cells, and clonal proliferation of EBV-infected cells and T-cells was detected. Although we suspected malignant lymphoma, her condition improved following immunosuppressive therapy. A similar case was recently reported; therefore, this case is the second case of IM with EBV-infected CD8-positive cells and clonal proliferation of EBV-infected cells. Our results demonstrate that the clonal proliferation of EBV-infected cells is not always an indication for chemotherapy in the primary infection phase and that monitoring the EBV viral load is useful for therapeutic decision-making.

Validation of Antiviral Potential of Herbal Ethnomedicine

Natural products are the basis of treatment since the dawn of human civilization, and modern medicine has gradually developed, over the years, by scientific and observational efforts from traditional medicine. Today most of the synthetic drugs showed adverse and unacceptable side effects, however, impressive bioactivities with reduced toxicities were reported for many botanicals against several chronic or difficult-to-treat diseases. A whole range of viral diseases including human immunodeficiency virus/acquired immunodeficiency syndrome, severe acute respiratory syndrome, Rabies, Dengue, and Herpes need effective drugs. Considerable research has been carried out on the pharmacognosy, chemistry, pharmacology, and therapeutics of traditional medicines of diverse cultures, and many pharmaceutical companies have renewed their strategies for antiviral drug development where no effective drugs or vaccine exist. Thus, phytochemicals with antiviral potentials need to be studied in depth with standardization, chemical isolation, effectivity, molecular mechanism, along with in vivo toxicity and efficacy to reduce cost and time. This review will portray the scientific approaches and methodologies used for the development of antiviral leads from traditional medicines against selected genetically and functionally diverse viral infections.

Large-scale analysis of viral nucleic acid spectrum in temporal lobe epilepsy biopsies

OBJECTIVE

Chronic inflammatory processes are important promotors of temporal lobe epilepsy (TLE) development. Based on human herpesvirus 6 (HHV-6) DNA detection in brain tissue from patients with TLE, an association of persistent viral infection with TLE has been discussed. Individual studies reported increased HHV-6 DNA in patients with clinical signs of previous inflammatory brain reaction, that is, febrile seizures or meningoencephalitis. However, detection rates vary considerably between different studies. Here we performed a large-scale analysis of viral DNA/RNA spectrum in high-quality TLE biopsies. In addition to all Herpesviridae, we addressed potentially relevant neurotropic RNA viruses.

METHODS

DNA and RNA were extracted from 346 fresh-frozen tissue samples removed by epilepsy surgery. Real-time polymerase chain reaction (PCR) and nested PCR were performed for Herpesviridae and RNA viruses, respectively. Clinical data were analyzed for earlier signs of inflammatory brain reactions. Fresh-frozen hippocampal tissue samples from patients without chronic central nervous system (CNS) disease served as controls (n = 62). Seven previous PCR studies with overall 178 TLE patients were additionally analyzed regarding a correlation of clinical parameters and HHV-6 detection.

RESULTS

PCR revealed HHV-6B DNA in 34 specimens (9.8%) from TLE patients. HHV-6B DNA was also present in eight control samples (12.9%; p > 0.05), but showed a lower virus concentration (p < 0.001). Other herpesviruses and RNA viruses were virtually absent. In patients with clinical signs of previous brain inflammation, HHV-6B DNA was observed in 15.0%, whereas only 6.3% of the samples from patients without febrile seizures or meningoencephalitis were positive for HHV-6B DNA (p < 0.05). A meta-analysis of the eight HHV-6 PCR studies revealed similar results.

SIGNIFICANCE

This biopsy-based study shows no differences in frequency of HHV-6B DNA detection between TLE patients and controls. These results do not support the hypothesis of a persistent HHV-6B infection as a major pathogenetic factor in TLE. However, the higher virus load in TLE patients and the increased detection rate of HHV-6B DNA in patients with previous inflammatory brain reactions require further investigations.

CD137 expression is induced by Epstein-Barr virus infection through LMP1 in T or NK cells and mediates survival promoting signals

To clarify the mechanism for development of Epstein-Barr virus (EBV)-positive T- or NK-cell neoplasms, we focused on the costimulatory receptor CD137. We detected high expression of CD137 gene and its protein on EBV-positive T- or NK-cell lines as compared with EBV-negative cell lines. EBV-positive cells from EBV-positive T- or NK-cell lymphoproliferative disorders (EBV-T/NK-LPDs) patients also had significantly higher CD137 gene expression than control cells from healthy donors. In the presence of IL-2, whose concentration in the serum of EBV-T/NK-LPDs was higher than that of healthy donors, CD137 protein expression was upregulated in the patients' cells whereas not in control cells from healthy donors. In vitro EBV infection of MOLT4 cells resulted in induction of endogenous CD137 expression. Transient expression of LMP1, which was enhanced by IL-2 in EBV-T/NK-LPDs cells, induced endogenous CD137 gene expression in T and NK-cell lines. In order to examine in vivo CD137 expression, we used EBV-T/NK-LPDs xenograft models generated by intravenous injection of patients' cells. We identified EBV-positive and CD8-positive T cells, as well as CD137 ligand-positive cells, in their tissue lesions. In addition, we detected CD137 expression on the EBV infected cells from the lesions of the models by immune-fluorescent staining. Finally, CD137 stimulation suppressed etoposide-induced cell death not only in the EBV-positive T- or NK-cell lines, but also in the patients' cells. These results indicate that upregulation of CD137 expression through LMP1 by EBV promotes cell survival in T or NK cells leading to development of EBV-positive T/NK-cell neoplasms.

Association of higher methotrexate dose with lymphoproliferative disease onset in rheumatoid arthritis patients

OBJECTIVE

Methotrexate (MTX) is used as an anchor drug for rheumatoid arthritis (RA). Lymphoproliferative disease (LPD) occasionally develops in patients treated with MTX, and is known as MTX-associated LPD (MTX-LPD). Although MTX-LPD occurs mainly in RA patients, it has not been established if MTX administration is an independent risk factor for LPD in RA patients. We examined the clinical characteristics of MTX-LPD in Japanese RA patients and attempted to determine the risk factors for MTX-LPD development.

METHODS

We performed a nested case-control study on RA patients. We enrolled 5,753 RA patients from Kagawa, Japan. In age- and sex-matched patients, we separated patients who did not develop LPD under MTX treatment (MTX non-LPD group) from those that did (MTX-LPD group) and conducted a comparative examination. We used multivariate analysis to determine the independent risk factors for MTX-LPD onset.

RESULTS

There were 28 patients in the MTX-LPD group and 125 patients in the MTX non-LPD group. Multivariate analysis of the parameters extracted by univariate analysis revealed that the mean MTX dose was a risk factor for MTX-LPD after adjusting for age; therefore, higher MTX dose is associated with LPD onset in RA patients.

CONCLUSION

MTX is an independent risk factor for LPD onset in Japanese RA patients.

Host genetic variants and gene expression patterns associated with Epstein-Barr virus copy number in lymphoblastoid cell lines

Lymphoblastoid cell lines (LCLs) are commonly used in molecular genetics, supplying DNA for the HapMap and 1000 Genomes Projects, used to test chemotherapeutic agents, and informing the basis of a number of population genetics studies of gene expression. The process of transforming human B cells into LCLs requires the presence of Epstein-Barr virus (EBV), a double-stranded DNA virus which through B-cell immortalisation maintains an episomal virus genome in every cell of an LCL at variable copy numbers. Previous studies have reported that EBV alters host-gene expression and EBV copy number may be under host genetic control. We performed a genome-wide association study of EBV genome copy number in LCLs and found the phenotype to be highly heritable, although no individual SNPs achieved a significant association with EBV copy number. The expression of two host genes (CXCL16 and AGL) was positively correlated and expression of ADARB2 was negatively correlated with EBV copy number in a genotype-independent manner. This study shows an association between EBV copy number and the gene expression profile of LCLs, and suggests that EBV copy number should be considered as a covariate in future studies of host gene expression in LCLs.

Increased T-cell responses to Epstein-Barr virus with high viral load in patients with Epstein-Barr virus-positive diffuse large B-cell lymphoma

The immunological status of patients with Epstein-Barr virus-positive diffuse large B-cell lymphoma (EBV+ DLBCL) without obvious immunodeficiency has not been elucidated. A multicenter prospective study was conducted to assess pretreatment T-cell responses to EBV, EBV-DNA load and anti-EBV antibody in these patients. The proliferative and interferon (IFN)-γ-producing capacity of T-cells in response to autologous B-lymphoblastoid cell lines was determined using carboxyfluorescein diacetate succinimidyl ester (CFSE)-based assay. Frequencies of EBV-specific CD4+ T-cells in patients with EBV+ DLBCL (n = 13) were significantly higher than in healthy controls (HCs) (n = 16) after both ex vivo and in vitro stimulation. Frequencies of EBV-specific CD8+ T-cells in patients with EBV+ DLBCL tended to be higher than in HCs after in vitro stimulation. Patients with EBV+ DLBCL also showed increased immunoglobulin G (IgG) responses to lytic EBV-encoded antigens. Pretreatment plasma EBV-DNA level was significantly higher in patients with EBV+ DLBCL than in patients with EBV- DLBCL or HCs. In conclusion, EBV-specific T-cells showed increased reactivity, accompanied by higher levels of plasma virus DNA in patients with EBV+ DLBCL.

A single-tube nucleotide isolation reagent for the quantitative PCR detection of virus in body fluids

A high-salt reagent composed of guanidinium thiocyanate, guanidine hydrochloride, urea, sodium citrate, and other compounds was designed for the single-tube isolation of viral nucleotides from body fluids. The single-tube reagent was used for the extraction of SIV RNA and HBV DNA from standard virus stock dilutions and virus-positive samples. The sensitivity and reproducibility of the single-tube reagent were analysed via quantitative PCR assays. The results revealed that the single-tube reagent can facilitate quantitative PCR-mediated detection in a reaction system with a 25-μl volume using only 100 μl of a body fluid sample and reaches a sensitivity of up to 50 copies/ml. The low coefficients of variance of both the HBV and SIV standard stock results indicate the excellent reproducibility of the single-tube reagent. A Bland-Altman analysis of the assay results from the SIV- and HBV-positive samples revealed that the single-tube reagent can precisely extract both RNA and DNA viral nucleotides from virus-positive samples. All of the isolation steps were performed in a single tube and were completed in no more than 35 min. The only major equipment required is a high-speed freezing centrifuge. The single-tube reagent is economical and easy to use and does not require any complex equipment.

Prognostic factors of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in children: report of the Japan Histiocytosis Study Group

BACKGROUND

Despite several advances in the treatment of Epstein-Barr virus (EBV) in recent years, patients with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) do not always show satisfactory outcomes. We here conducted a nationwide survey in Japan to identify prognostic factors of EBV-HLH in children with this disease in an effort to improve the management and the outcomes of these patients.

PROCEDURE

Between January 2003 and June 2008, we enrolled 98 children younger than 18 years of age who were diagnosed with EBV-HLH. We then studied the clinical characteristics and laboratory findings at the time of diagnosis with the aim to identify prognostic factors for EBV-HLH.

RESULTS

The mean age of onset of EBV-HLH was 3.9 ± 2.8 years. Most of our patients presented with fever, hepatosplenomegaly, lymphadenopathy, and hemophagocytosis of bone marrow. Sixty-two percent of patients showed T cell clonality, and 97% had EBV infection in either T or natural killer cells. Most patients (60%) were treated with a multi-agent chemotherapeutic regimen, including corticosteroid, etoposide, and cyclosporine. After initial treatment, 90.3% of patients were in remission, and 7 patients (8.2%) experienced recurrence of EBV infection. Among several prognostic factors, patients with both hyperbilirubinemia (>1.8 mg/dl) and hyperferritinemia (>20,300 ng/ml) at the time of diagnosis had significantly poorer outcomes than those with low serum bilirubin and ferritin levels.

CONCLUSIONS

These findings suggest that the therapeutic strategy for children with EBV-HLH could be tailored according to the laboratory findings at diagnosis.

Anti-tumor effects of suberoylanilide hydroxamic acid on Epstein-Barr virus-associated T cell and natural killer cell lymphoma

The ubiquitous Epstein–Barr virus (EBV) infects not only B cells but also T cells and natural killer (NK) cells and is associated with various lymphoid malignancies. Recent studies have reported that histone deacetylase (HDAC) inhibitors exert anticancer effects against various tumor cells. In the present study, we have evaluated both the in vitro and in vivo effects of suberoylanilide hydroxamic acid (SAHA), an HDAC inhibitor, on EBV-positive and EBV-negative T and NK lymphoma cells. Several EBV-positive and EBV-negative T and NK cell lines were treated with various concentrations of SAHA. SAHA suppressed the proliferation of T and NK cell lines, although no significant difference was observed between EBV-positive and EBV-negative cell lines. SAHA induced apoptosis and/or cell cycle arrest in several T and NK cell lines. In addition, SAHA increased the expression of EBV-lytic genes and decreased the expression of EBV-latent genes. Next, EBV-positive NK cell lymphoma cells were subcutaneously inoculated into severely immunodeficient NOD/Shi-scid/IL-2Rγnull mice, and then SAHA was administered intraperitoneally. SAHA inhibited tumor progression and metastasis in the murine xenograft model. SAHA displayed a marked suppressive effect against EBV-associated T and NK cell lymphomas through either induction of apoptosis or cell cycle arrest, and may represent an alternative treatment option.

Duplex realtime PCR method for Epstein-Barr virus and human DNA quantification: its application for post-transplant lymphoproliferative disorders detection

INTRODUCTION

The quantification of circulating Epstein-Barr virus (EBV) DNA is used to monitor transplant patients as an early marker of Post-Transplant Lymphoproliferative Disorders (PTLD). So far no standardized methodology exists for such determination.

OBJECTIVE

Our purpose was to develop and validate a real-time PCR assay to quantify EBV DNA in clinical samples from transplant recipients.

METHODS

A duplex real-time PCR method was developed to amplify DNA from EBV and from a human gene. The EBV load was determined in peripheral blood mononuclear cells (PBMC), plasma and oropharyngeal tissue from 64 non-transplanted patients with lymphoid-hypertrophy (Non-Tx), 47 transplant recipients without PTLD (Tx), 54 recipients with PTLD (Tx-PTLD), and 66 blood donors (BD). WinPEPI, version 11.14 software was used for statistical analysis.

RESULTS

Analytical validation: the intra and inter-assays variation coefficients were less than 4.5% (EBV-reaction) and 3% (glyceraldehyde 3-phosphate dehydrogenase - GAPDH reaction). Linear ranges comprised 10(7)-10 EBV genome equivalents (gEq) (EBV-reaction) and 500,000-32 human gEq (GAPDH-reaction). The detection limit was 2.9 EBV gEq (EBV-reaction). Both reactions showed specificity. Application to clinical samples: higher levels of EBV were found in oropharyngeal tissue from transplanted groups with and without PTLD, compared to Non-Tx (p<0.05). The EBV load in PBMC from the groups of BD, Non-Tx, Tx and Tx-PTLD exhibited increasing levels (p<0.05). In BD, PBMC and plasma, EBV loads were undetectable.

CONCLUSIONS

The performance of the assay was suitable for the required clinical application. The assay may be useful to monitor EBV infection in transplant patients, in particular in laboratories from low-income regions that cannot afford to use commercial assays.

Long-term outcome after haploidentical stem cell transplant and infusion of T cells expressing the inducible caspase 9 safety transgene

Adoptive transfer of donor-derived T lymphocytes expressing a safety switch may promote immune reconstitution in patients undergoing haploidentical hematopoietic stem cell transplant (haplo-HSCT) without the risk for uncontrolled graft versus host disease (GvHD). Thus, patients who develop GvHD after infusion of allodepleted donor-derived T cells expressing an inducible human caspase 9 (iC9) had their disease effectively controlled by a single administration of a small-molecule drug (AP1903) that dimerizes and activates the iC9 transgene. We now report the long-term follow-up of 10 patients infused with such safety switch-modified T cells. We find long-term persistence of iC9-modified (iC9-T) T cells in vivo in the absence of emerging oligoclonality and a robust immunologic benefit, mediated initially by the infused cells themselves and subsequently by an apparently accelerated reconstitution of endogenous naive T lymphocytes. As a consequence, these patients have immediate and sustained protection from major pathogens, including cytomegalovirus, adenovirus, BK virus, and Epstein-Barr virus in the absence of acute or chronic GvHD, supporting the beneficial effects of this approach to immune reconstitution after haplo-HSCT. This study was registered at www.clinicaltrials.gov as #NCT00710892.

Utility of real-time PCR analysis for appropriate diagnosis for keratitis

Real-time polymerase chain reaction (PCR) is a quantitative method to measure the amount of amplified PCR product in real time with high sensitivity. We have applied this method to detect pathogens in cases of keratitis with an unknown cause. The scraped corneal epithelium for epithelial keratitis or aqueous humor for stromal or endothelial keratitis was obtained and DNA was extracted. The DNA from specific pathogens was amplified using specific primers and TaqMan probe, and assessed quantitatively. Here, we review previously reported noteworthy examples of keratitis diagnosed by our real-time PCR system as follows: cases with Acanthamoeba keratitis whose causative pathogen was only detected by real-time PCR despite not being detected by histological examination and culture; zoster sine herpete with atypical pseudodendrite; acyclovir-resistant herpetic keratitis estimated by changes in viral DNA copy numbers before and after treatment; and corneal endotheliitis positive for cytomegalovirus, human herpes virus-7, or human herpes virus-8. Real-time PCR helps ophthalmologists to make an early diagnosis and provide appropriate treatment for keratitis with complex clinical appearances.

Comparison of two laboratory extraction techniques for the detection of Epstein-Barr virus in the saliva of nasopharyngeal carcinoma patients

AIM

The aim of the present study was to compare the effectiveness of DNA extraction using an extraction kit against the standard boiling technique for the detection of Epstein-Barr virus (EBV) DNA in nasopharyngeal carcinoma (NPC) patients.

METHODS

Stimulated whole saliva samples from newly-diagnosed NPC patients were collected. EBV DNA was extracted by both techniques (n = 23) followed by quantitative real-time polymerase chain reaction (PCR) using the primer/probe set for BALF5.

RESULTS

The results of the quantitative real-time PCR were reproducible in both groups. The two techniques were moderately correlated (r = 0.67, P < 0.05), and the degree of agreement was good. However, the mean EBV DNA level in the boiling group (3.02 ± 8.67 × 10(6) copies/μL) was significantly higher than the extraction kit group (1.15 ± 2.66 × 10(6) copies/μL) (P < 0.05). The EBV DNA level was higher in patients at an advanced overall stage (P = 0.05).

CONCLUSION

The results of the present study showed that the performance of the extraction kit was not superior to the simple boiling technique for the detection of salivary EBV DNA in NPC patients using real-time PCR. The salivary EBV DNA level in patients at an advanced overall stage appeared to be higher than in patients at an early stage.

Real-Time PCR of cytomegalovirus and Epstein-Barr virus in adult Egyptian patients with systemic lupus erythematosus

OBJECTIVE

Infections may act as environmental triggers for induction of systemic lupus erythematosus (SLE). We sought to explore the relative frequencies of Epstein-Barr virus (EBV) and human cytomegalovirus (CMV) in adult Egyptian patients with SLE and their correlation with disease activity and damage.

METHODS

Thirty-three consecutive adult patients satisfying the 1997 American College of Rheumatology (ACR) Classification Criteria for SLE and 30 healthy controls were included in this case-control study. All patients were subjected to complete clinical and laboratory evaluation to determine the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR). Sera from both groups were analyzed for immunoglobulin M (IgM) and IgG antibodies against CMV and EBV. Qualitative real time polymerase chain reaction (PCR) for both viruses was performed for all SLE patients.

RESULTS

Almost all SLE patients 32/33 (96.9%) were positive for IgG anti-CMV antibodies versus 20/30 in the control group (66.6%) (P = 0.002). All SLE patients were positive for IgG anti-EBV antibodies compared to 25 in the control group (100% vs. 83.3%, P = 0.02). CMV and EBV DNA were detected by PCR in 30.3% and 51.5% of SLE patients, respectively. A statistically significant lower SLEDAI was found in PCR positive patients for EBV compared to negative patients (9.6 ± 5.2 vs. 13.1 ± 3.1, respectively P = 0.041).

CONCLUSIONS

Adult Egyptian patients with SLE had higher frequencies of anti-CMV and EBV IgG compared to healthy controls. Furthermore, our single point assessment of SLEDAI suggested that exposure to EBV infection might be associated with a lower disease activity.

Anti-neutrophil cytoplasmic antibody-associated vasculitis associated with infectious mononucleosis due to primary Epstein-Barr virus infection: report of three cases

Although the aetiology of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis remains unclear, it is generally believed that environmental factors such as infections contribute to its development of ANCA-associated vasculitis. Prior Epstein–Barr virus (EBV) infection is reported to be a trigger of systemic vasculitis. We herein report three cases of ANCA-associated vasculitis presenting with infectious mononucleosis due to primary EBV infection. The causal link between the two pathologies could not be proved, but primary EBV infection may play a role in the initiation or exacerbation of ANCA-associated vasculitis. Future studies are necessary to determine the interaction between these diseases conditions.

Possible autoimmune hepatitis induced after chronic active Epstein-Barr virus infection

Chronic active Epstein-Barr virus infection (CAEBV) can be manifested in a variety of systemic conditions, including interstitial pneumonia, malignant lymphoma, and coronary aneurysm. Sometimes it may be associated with hepatic failure, although the mechanism underlying CAEBV-related hepatotoxicity remains unclear. We encountered a case of autoimmune hepatitis (AIH) associated with CAEBV. A 61-year-old male was referred to our hospital because of abnormal liver enzyme levels after initial diagnosis of CAEBV had been made by laboratory tests and liver biopsy. On admission, positivity for anti-nuclear antibody was evident, and examination of the liver biopsy specimen showed findings compatible with AIH. Steroid administration was initiated, and the liver function parameters subsequently improved. Although phenotypic changes in liver biopsy specimens are rare in this condition, the present case could provide clues to the possible pathogenesis of AIH.

Association of Cytomegalovirus with Infantile Hepatitis

Infantile hepatitis is occasionally seen in apparently healthy children. In most cases, the etiology of the infection is uncertain. However, cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus-6 (HHV-6), human herpesvirus-7 (HHV-7), human parvovirus B19, and TT virus (TTV) are considered to be associated with hepatitis in children. The objective of this study was to investigate the correlations between these viruses and infantile hepatitis. Twenty-six children from 1 to 24 months old (median age, 7 months) who had liver dysfunction of unknown etiology were enrolled in this study. Plasma samples were examined by a real-time PCR assay for CMV, EBV, HHV-6, HHV-7, parvovirus B19, and TTV DNA. The DNA of CMV was detected in the plasma of four patients (15.4%) and was detected significantly more often in the patient group than in the control group. The CMV-infected patients were 1 to 3 months old, which was significantly younger than the remaining patients. The serological findings did not always correlate with the results of the real-time PCR assay. The DNA of TTV was detected in four patients (15.4%), while human parvovirus B19 DNA was detected in three (11.5%). However, the detection frequencies of these viral DNAs were not significantly different from those in the control groups, and some of these patients had co-infections. These results indicate that CMV might be one of the major pathogens responsible for infantile hepatitis; however, serological tests have limited utility for the diagnosis of CMV infection in young children.

Impact of Epstein-Barr virus load, virus genotype, and frequency of the 30 bp deletion in the viral BNLF-1 gene in patients harboring the human immunodeficiency virus

Patients infected with the human immunodeficiency virus (HIV) are at higher risk of developing Epstein-Barr Virus (EBV)-associated lymphomas. The usefulness of monitoring EBV in peripheral blood mononuclear cells (PBMCs) of patients infected with HIV has not been established. The aim of this study was to evaluate the EBV viral load in PBMCs, the frequency of viral genotypes, and the presence of the 30-bp deletion in the BNLF-1 gene. DNA samples from 156 patients attending the HIV/AIDS Day Clinic at Botucatu School of Medicine, Sao Paulo State University were evaluated. The EBV viral load was detectable by real time PCR in 123/156 (78.8%) cases and was higher in patients not receiving antiretroviral treatment or under therapeutic failure than in patients under successful highly active antiretroviral therapy (HAART) (P = 0.0076). Overall, the profile of patients with high EBV viral load included elevated HIV viremia (P = 0.0005), longer time of HIV diagnosis (P = 0.0026), and increased levels of T CD8 (+) lymphocytes (P = 0.0159). The successful amplification of the EBNA-2 gene by nested-PCR was achieved in 95 of 123 (77.2%) cases, of which 75.8% were EBV-1, 9.5% EBV-2, and 14.7% were co-infected with both EBV-1 and -2. The analysis of the BNLF-1 gene was possible in 99 of 123 (80.5%) cases, of which 50.5% had the 30-bp deletion. EBV-1 was more common than EBV-2, which may reflect the fact that the cohort was predominantly Caucasian and heterosexual.

Cell-free epstein-barr viral loads in childhood hodgkin lymphoma: a study from South India

Cell-free Epstein-Barr viral (EBV) DNA is detectable in plasma of patients with EBV-related lymphomas. The aim of this study was to evaluate the utility of plasma EBV DNA as a biomarker of EBV association in childhood Hodgkin lymphoma (HL). Furthermore, an attempt was made to evaluate the effectiveness of viral quantitation for assessing response to chemotherapy. Thirteen cases of childhood HL were included in this study. All 13 cases were EBV associated as reflected by expression of EBV LMP1 in the tumor specimen. Eighty-five percent had detectable EBV DNA levels; viral loads ranging from 2.9 to 156.2 × 10³ copies/ml (mean 29 × 10³ copies/ml); while in 2 patients and 30 controls tested, viral DNA was undetectable. In four patients, follow-up samples were available after three cycles of chemotherapy; all had EBV DNAemia prior to chemotherapy but undetectable EBV DNA posttherapy. This corroborated with complete response in these four patients. Plasma EBV viral load quantification maybe a useful tool for detecting EBV association with lymphomas and in monitoring response to treatment in childhood HL in centers with limited resources, more so in India where majority of childhood HL is likely to be EBV associated. This is the first Indian study estimating plasma EBV viral loads in HL.

Determining EBV load: current best practice and future requirements

EBV, a gammaherpesvirus and the pathogenic agent for infectious mononucleosis, is also associated with a broad spectrum of lymphoid and epithelial malignancies in immunocompetent and immunosuppressed individuals. EBV-DNA-load measurement by PCR has been shown to be a potential tool for the diagnosis of these diseases, a prognostic factor of their outcome and a successful method to monitor immunosuppressed patients. Since the end of 2011, there is an international WHO standard reference for EBV quantification available; however, many questions still remain; for instance about the optimal amplified region of the EBV genome, or the best-used specimen for EBV detection. Additionally, the optimal specimen and amplified region may vary in different malignancies. In this article, the authors review the different methods to measure EBV load, focus on the best-used specimen for the different EBV-associated malignancies and discuss future requirements and opportunities for EBV-load measurement.

The use of RT-PCR for determination of separate end-points for the strains IB H120 and IB D274 in titration of the combination vaccine Poulvac IB® primer

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Reading of live virus titrations by PCR.

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Determination of endpoints for different viruses in one titration by PCR.

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Similarity of titration results of reading by visual examination and reading by PCR.

Poulvac IB^® Primer is a lyophilized vaccine containing two attenuated infectious bronchitis strains in one vial, IB H120 and IB D274. For quantification of the viral content of the vaccine, dilution series of the final product are inoculated in embryonated chicken eggs. After the incubation period of seven days standard practice is for the embryos to be taken from each egg and examined visually for IB specific lesions; these readings are used to determine an end-point in viral titrations. The result is a titre value to which both strains contribute. However, it is not clear what the live virus titre is for strain IB H120 and for strain IB D274. In order to determine end-points in the titration for each of the two strains, we collected the allantoic fluids from each egg after the incubation period and tested these for the presence of IB H120 and IB D274 by a strain specific reverse phase PCR. Based on the data obtained by PCR we were able to determine an end-point for each of the two strains. For a given commercial batch of Poulvac IB primer we determined titres of 10^6.31 EID₅₀ per vial for IB H120 and 10^6.59 EID₅₀ for IB D274 using PCR for end-point determination. These end-points matched well with the end-point determined for both strains cumulatively after visual examination, i.e. 10^6.67 EID₅₀ per vial. It is concluded that PCR is a suitable means to determine end-points in titrations of live viruses.

Empirical voriconazole therapy for febrile neutropenic patients with hematological disorders: a prospective multicenter trial in Japan

An open-label, prospective, multicenter study was conducted between October 2006 and March 2010 to assess the efficacy and safety of intravenous voriconazole (VRCZ) as empirical therapy for antibiotic-refractory febrile neutropenia in Japanese patients with hematological disorders. In addition, to find the patient groups that may benefit from antifungal therapy, the definition of invasive fungal infection proposed by EORTC/MSG (2002) was assessed in this study. Plasma (1-3)-β-d-glucan and Aspergillus PCR in blood were also measured to improve the diagnostic accuracy. A total of 103 patients (median age, 59 years), including 25 undergoing induction chemotherapies and 19 allogeneic hematopoietic cell transplants, were evaluable. Sixty-nine percent of the patients achieved resolution of clinical symptoms and 31 % achieved treatment success, defined as fulfilling the previously described five-part composite endpoint. Although VRCZ was discontinued in 9.7 % of the patients because of adverse effects, all the patients recovered soon after discontinuation of VRCZ. The treatment success rate of VRCZ appeared to be higher in patients categorized as “not classified” compared with “possible invasive fungal disease” according to the EORTC/MSG criteria. Moreover, six “not classified” patients were positive for either plasma (1-3)-β-d-glucan (n = 5) or Aspergillus PCR in blood (n = 2). The present study demonstrates that empirical VRCZ therapy is safe and effective in Japanese patients. Additionally, (1-3)-β-d-glucan and Aspergillus PCR tests were expected to provide additional information on the diagnosis of invasive fungal infections.

Plasma viral microRNA profiles reveal potential biomarkers for chronic active Epstein-Barr virus infection

BACKGROUND

Chronic active Epstein-Barr virus (CAEBV) infection has high mortality and morbidity, and biomarkers for disease severity and prognosis are required. MicroRNAs (miRNAs) are small noncoding RNAs, and EBV encodes multiple miRNAs. Because plasma contains sufficiently stable miRNAs, circulating EBV-associated miRNA profiles were investigated as novel biomarkers in CAEBV infection.

METHODS

Plasma miRNA expression was assessed for 12 miRNAs encoded within 2 EBV open reading frames (BART and BHRF). Expression levels were investigated in 19 patients with CAEBV infection, 14 patients with infectious mononucleosis, and 11 healthy controls. Relative expression levels of plasma miRNAs were determined by TaqMan probe-based quantitative assay.

RESULTS

Plasma miR-BART1-5p, 2-5p, 5, and 22 levels in patients with CAEBV infection were significantly greater than those in patients with infectious mononucleosis and in controls. Plasma miR-BART2-5p, 4, 7, 13, 15, and 22 levels were significantly elevated in patients with CAEBV infection with systemic symptoms, compared with levels in patients with no systemic symptoms. The levels of miR-BART2-5p, 13, and 15 showed clinical cutoff values associated with specific clinical conditions, in contrast to plasma EBV loads.

CONCLUSIONS

Levels of specific plasma EBV miRNAs were elevated differentially in patients with CAEBV infection. Several EBV miRNAs, particularly miR-BART2-5p, 13, and 15, are potentially biomarkers of disease severity or prognosis.

Persistent low level Epstein-Barr virus DNAemia in childhood cancer survivors

BACKGROUND

Clinical observation of Epstein-Barr virus (EBV) status has not documented in childhood cancer survivors (CCSs) sustaining long-term remission of malignant diseases. Thus, the aim of this study was to evaluate the EBV status in children with various malignant diseases after they completed their treatments.

PATIENTS AND METHODS

Thirty consecutive children with various malignant diseases previously received treatment at the University of Tsukuba Hospital. Nine cases had acute lymphoblastic leukemia (ALL), 10 had solid tumors, 4 had lymphoma, 4 had CNS tumors, and 3 had acute myeloid leukemia (AML). EBV DNA in 328 whole blood samples were monitored by real-time QPCR for all cases after treatment. Clinical records and laboratory data were also reviewed.

RESULTS

There were 6/30 (20%) cases with continuous detection of EBV DNA while there were 24/30 (80%) cases without continuous EBV DNA. EBV DNAemia was persistently observed in 4/9 (44.4%) cases with ALL and in 2/4 (50%) cases with lymphoma. Persistent EBV DNAemia can be observed for >5 years without any EBV associated symptoms or diseases.

CONCLUSIONS

Childhood cancer survivors have persistent EBV DNAemia more frequently, which is thought to be observed in cases with ALL and lymphoma with higher tendency for >5 years after treatment. Persistent EBV DNAemia is frequent in CCSs aged 5-10 years. Any immunological alteration is speculative in a pathophysiology of persistent EBV DNAemia.

Epstein-Barr virus negativity among individuals older than 60 years is associated with HLA-C and HLA-Bw4 variants and tonsillectomy

Epstein-Barr virus (EBV) infects ≈ 95% of the adult population. The factors that confer protection in the remaining ≈ 5% remain unknown. In an exploratory study, we assessed immunogenetic factors and tonsillectomy in a cohort of 17 EBV-negative and 39 EBV-positive healthy individuals aged >60 years. Analyses of HLA genotypes revealed an association between EBV negativity and the presence of HLA-C-35T/T and/or HLA-Bw4 alleles. In addition, EBV-negative donors presented with a history of tonsillectomy more often than EBV-positive donors.

Quantification of Epstein-Barr virus DNA is helpful for evaluation of chronic active Epstein-Barr virus infection

Chronic active Epstein-Barr virus infection (CAEBV) presents with chronic or recurrent infectious mononucleosis-like symptoms, such as low-grade fever, liver dysfunction, lymphadenopathy, and hepatosplenomegaly. Immunological methods are useful for the diagnosis of viral infections. However, CAEBV patients do not necessarily have high titers of Epstein-Barr virus (EBV)-specific antibodies. Hosts that are immunocompromised after hematopoietic stem cell transplantations sometimes suffer from systemic EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and EBV-positive lymphoma. Patients with EBV-associated diseases are often diagnosed by analyses of bone marrow. Cytomegalovirus (CMV) can cause serious pneumonia or retinitis in immunocompromised hosts. In order to noninvasively understand the clinical status of patients with EBV-associated diseases, we conducted real-time polymerase chain reaction (PCR) methods in their peripheral blood in order to quantify EBV and CMV DNA levels, which reflect viral activity. Here, we describe a 30-year-old Japanese female patient with CAEBV. The patient had repeated fever, fatigue, and liver dysfunction. The histopathological results of liver biopsies were positive for EBV-encoded RNA-1. Acute hepatitis was associated with the EBV infection. The whole-blood EBV DNA levels were high and above 1.0 × 10⁷ copies/mL. After immunosuppressive and antiviral therapies, EBV DNA levels lowered. However, she had to receive bone marrow transplantation because of her EBV-HLH. As the number of lymphocytes increased in the post-transplantation period, EBV DNA levels gradually increased again. The simultaneous detection of CMV DNA was more sensitive than the CMV antigenemia test that is often used to diagnose CMV infections. Unfortunately, the patient died due to a fungal infection. Observing EBV DNA levels closely with real-time quantitative PCR methods is helpful for evaluating the changes in the clinical course.

Clinical and virologic manifestations of primary Epstein-Barr virus (EBV) infection in Kenyan infants born to HIV-infected women

BACKGROUND

Human immunodeficiency virus (HIV) infection is a risk factor for Epstein-Barr virus (EBV)-associated lymphomas. Characterizing primary infection may elucidate risk factors for malignancy.

METHODS

To describe clinical and virologic manifestations of primary EBV infection among infants born to HIV-infected women, specimens were utilized from a cohort study conducted in Nairobi, Kenya. HIV and EBV viral loads were measured serially in plasma. EBV serology was performed on EBV DNA-negative infants. Monthly clinical examinations were performed by pediatricians.

RESULTS

The probability of EBV infection by 1 year of age was .78 (95% CI, .67-.88) in HIV-infected and .49 (95% CI, .35-.65) in HIV-uninfected infants (P < .0001). At 2 years, probability of EBV infection was .96 (95% CI, .89-.99) in HIV-infected infants. Peak EBV loads were higher in HIV-infected versus HIV-uninfected infants (median 2.6 vs 2.1 log10 copies/mL; P < .0001). The majority of HIV-infected infants had detectable EBV DNA for >3 months (79%). Primary EBV infection was associated with cough, fever, otitis media, pneumonia, hepatomegaly, splenomegaly, and hospitalization in HIV-infected infants; conjunctivitis and rhinorrhea in HIV-uninfected infants.

CONCLUSIONS

EBV infection occurs early in infants born to HIV-infected women. HIV infection was associated with more frequent and higher quantity EBV DNA detection.

Central nervous system complications and neuroradiological findings in children with chronic active Epstein-Barr virus infection

BACKGROUND

Although many neurological complications have been described in acute Epstein-Barr virus infection, few reports have discussed the central nervous system complications in chronic active Epstein-Barr virus (CAEBV) infection.

METHODS

We retrospectively surveyed the medical records of 14 patients with CAEBV infection in our institute. Neuroradiological studies were performed in 10 of these patients.

RESULTS

Five had no neurological symptoms, whereas two presented with posterior reversible encephalopathy syndrome, one presented with basal ganglia calcification, and one presented with falx cerebri hemorrhage. Although both of the posterior reversible encephalopathy syndrome cases developed epilepsy several years after recovering from prolonged neurological deterioration, the others had no neurological sequelae.

CONCLUSIONS

This study revealed that various central nervous system complications may occur during the clinical course in pediatric CAEBV patients.

EBNA-2 -deleted Epstein-Barr virus from P3HR-1 can infect rabbits with lower efficiency than prototype Epstein-Barr virus from B95-8

OBJECTIVES

To clarify characteristics on rabbit in vivo infection with type 2 EBV nuclear antigen (EBNA-2)-deleted Epstein-Barr virus (P3HR-1-EBV) and compare infectious efficacy of P3HR-1-EBV with previously reported prototype type 1 EBV from B95-8.

METHODS

Twelve Japanese White rabbits were inoculated with P3HR-1-EBV via intranasal or intravenous routes and autopsied on day 70-84.

RESULTS

In only 2 of 12 P3HR-1-EBV-inoculated rabbits, EBV-DNA was detected in peripheral blood mononuclear cells (PBMCs). BamHI M rightward reading frame (BMRF)-1, EBNA-1 and BamHI Z leftward reading frame (BZLF)-1-mRNA were intermittently expressed in PBMCs. In 1 infected rabbit with continuous detection of EBV-DNA in PBMCs, many EBER-1-positive lymphocytes were observed in germinal centers and/or marginal zones in some follicles of the appendix, and for the first time a lymphocyte with EBER-1 expression infiltrating in the squamous cell layer of the tonsils was found. The other rabbit with a transient detection of EBV-DNA in PBMCs had no EBER-1-positive lymphocytes in the tissues examined. Few EBER-1-positive lymphocytes were detected in some rabbits without detection of EBV-DNA in PBMCs.

CONCLUSIONS

P3HR-1-EBV showed less efficient infection in rabbits than EBV from the B95-8 cell line. However, a P3HR-1-EBV-inoculated animal model is meaningful because this is the first study of EBNA-2 function on in vivo EBV infection and it demonstrated the in vivo infectivity with lytic-type infection by EBNA-2-deleted EBV.

Effective control of Epstein-Barr virus infection following pediatric liver transplantation by monitoring of viral DNA load and lymphocyte surface markers

EBV-associated PTLD is a serious complication of liver transplantation. We performed periodical molecular EBV monitoring in 140 consecutive pediatric patients who had living-related liver transplantation in the National Center for Child Health and Development, Tokyo. Sixty-three of the 140 patients showed elevation of EBV DNA level to >10(2) copies/μg DNA and were further examined immunologically by flow cytometry, and the dose of tacrolimus and/or cyclosporine A was adjusted according to the results. The decrease in CD4/CD8 ratio and the increase in the number of HLA-DR(+) CD8(+) cells were observed in parallel with the decrease in EBV DNA load and in the number of CD19(+) CD23(+) cells following the reduction in immunosuppressive drugs. Analysis with HLA tetramers in a patient demonstrated a dramatic increase in the number of CD8(+) T cells specific to the EBV latent protein LMP2 accompanying the decline of EBV DNA load, suggesting that T cells of this specificity were actually involved in the control of EBV infection. No clinically apparent PTLD has developed in the 140 recipients, suggesting that our program of EBV control by molecular EBV monitoring coupled with lymphocyte phenotype analyses is effective in controlling EBV infection in pediatric liver transplant recipients.

Epstein-Barr virus: general factors, virus-related diseases and measurement of viral load after transplant

The Epstein-Barr virus is responsible for infectious mononucleosis syndrome and is also closely associated to several types of cancer. The main complication involving Epstein-Barr virus infection, both in recipients of hematopoietic stem cells and solid organs, is post-transplant lymphoproliferative disease. The importance of this disease has increased interest in the development of laboratory tools to improve post-transplant monitoring and to detect the disease before clinical evolution. Viral load analysis for Epstein-Barr virus through real-time polymerase chain reaction is, at present, the best tool to measure viral load. However, there is not a consensus on which sample type is the best for the test and what is its predictive value for therapeutic interventions.

Sequential monitoring of serum IL-6, TNF-α, and IFN-γ levels in a CAEBV patient treated by plasma exchange and immunochemotherapy

We report the case of a female patient with chronic active Epstein-Barr virus infection (CAEBV) accompanied by hemophagocytic syndrome (HPS). On admission, she presented with severe liver dysfunction and disseminated intravascular coagulation with elevation of serum IL-6, TNF-α, and IFN-γ levels. Plasma exchange (PE) followed by immunochemotherapy with prednisolone, cyclosporine A, and VP16 was performed. PE decreased serum cytokine levels dramatically and improved liver function. Following immunochemotherapy, CAEBV became inactive. Four months after discharge, however, CAEBV relapsed with HPS, and serum cytokine levels were extremely elevated again. There was no response to immunochemotherapy, and the patient died 1 day after admission. We examined the cytokines in five additional untreated-CAEBV patients and determined that they were elevated above the normal level in all patients. These results suggest that inflammatory cytokines may have roles in the development of CAEBV, and that their depletion can be an effective treatment for this disease.

Exploring the prevalence of ten polyomaviruses and two herpes viruses in breast cancer

Several different viruses have been proposed to play a role in breast carcinogenesis. The aim of this study was to investigate the prevalence of a subset of viruses in breast cancer tissue. We investigated the prevalence of 12 DNA viruses: EBV and CMV from the Herpesviridae family and SV40, BKV, JCV, MCV, WUV, KIV, LPV, HPyV6, HPyV7, and TSV from the Polyomaviridae family in 54 fresh frozen breast tumour specimens. Relevant clinical data and basic lifestyle data were available for all patients. The tissue samples were DNA extracted and real-time PCR assays were used for viral detection.The highest prevalence, 10% (5/54), was found for EBV. MCV, HPyV6, and HPyV7 were detected in single patient samples (2% each), while WUV, KIV, JCV, BKV, LPV, SV40, TSV and CMV were not detected in the 54 breast cancer specimens analysed here. Further investigations are needed to elucidate the potential role of viruses, and particularly EBV, in breast carcinogenesis.

Host factors associated with the kinetics of Epstein-Barr virus DNA load in patients with primary Epstein-Barr virus infection

The aims of this study were to elucidate the kinetics of Epstein-Barr virus (EBV) DNA load in serially collected peripheral blood mononuclear cells of patients with primary EBV infection, and to determine the correlated host factors. Blood samples were collected from 24 patients with primary EBV infection. EBV DNA copy numbers were measured using real-time polymerase chain reaction. Based on the kinetics of EBV DNA load, the 24 patients were divided into two groups: rapid regression and slow regression. Eighteen of the 24 patients (75%) were included in the slow regression and 6 (25%) in the rapid regression group. No statistically significant differences were observed between the two groups in clinical features and laboratory findings. However, acute phase (3 to 10 days after the onset of the illness) serum samples from six children in the slow regression and four in the rapid regression group revealed significantly higher serum interleukin (IL)-1β (P= 0.018), IL-12 (P= 0.009), tumor necrosis factor-α (P= 0.019), interferon-inducible protein 10, and monokine induced by interferon γ concentrations in the rapid regression than the slow regression group. On the other hand, sera from six children in the slow regression and four in the rapid regression group in the convalescent phase (14 to 21 days after the onset of the illness) showed no statistically significant differences between the two groups in these biomarker concentrations. Based on this, it was concluded that the kinetics of EBV DNA load can be divided to two different patterns after primary EBV infection, and immune response might be associated with viral clearance.

Application of flow cytometric in situ hybridization assay to Epstein-Barr virus-associated T/natural killer cell lymphoproliferative diseases

Epstein-Barr virus (EBV) infects various types of lymphocytes and is associated with not only B cell-origin lymphoma, but also T or natural killer cell lymphoproliferative diseases (T/NK LPD). Recently, we established a novel assay to identify EBV-infected cells using FISH. Using this assay, dual staining with antibodies to both surface antigens and an EBV-encoded small RNA (EBER) probe can be performed. In the present study, we applied this recently developed FISH assay to EBV-associated T/NK LPD to confirm its diagnostic utility. Using FISH, we prospectively analyzed peripheral blood from patients with suspected EBV-associated T/NK LPD. The results were compared with those obtained using immunobead sorting followed by quantitative PCR. In all, 26 patients were included study. Using FISH, 0.15-67.0% of peripheral blood lymphocytes were found to be positive for EBER. Dual staining was used to determine EBER-positive cell phenotypes in 23 of 26 subjects (88.5%). In five of seven patients with hydroa vacciniforme-like lymphoma (an EBV-positive cutaneous T cell lymphoma), EBER-positive cells were identified as CD3(+) CD4(-) CD8(-) TCRγδ(+) T cells. Furthermore, in a 25-year-old male patient with systemic EBV-positive T cell LPD, two lymphocyte lineages were positive for EBER: CD4(+) CD8(-) and CD4(-) CD8(+) T cells. Thus, we confirmed that our newly developed assay is useful for quantifying and characterizing EBV-infected lymphocytes in EBV-associated T/NK LPD and that it can be used not only to complement the pathological diagnosis, but also to clarify the pathogenesis and to expand the spectrum of EBV-associated diseases.

Evaluation of multiplex polymerase chain reaction and microarray-based assay for rapid herpesvirus diagnostics

Rapid diagnosis is critical to minimize morbidity and mortality associated with infections of the central nervous system (CNS). In this study, we evaluated the performance of a multiplex polymerase chain reaction (PCR) and microarray-based method, Prove-it™ Herpes, in a routine clinical laboratory setting for the diagnostics of 7 herpesviruses in viral CNS infections. Cerebrospinal fluid samples (n = 495), which had arrived for diagnostics in the 5 participating laboratories, were analyzed for herpesvirus DNA both by the current PCR-based method of the laboratory and by the microarray assay. The sensitivity and specificity for the microarray assay were 93% and 99%, respectively. The microarray assay was considered as a rapid and robust diagnostic platform that was easily implemented into the laboratory workflow. The broad herpesvirus coverage and the small sample volume required by the assay could benefit the diagnostics and thus the treatment of life-threatening infections of the CNS, especially among immunocompromised patients.

Tumor-specific but not nonspecific cell-free circulating DNA can be used to monitor disease response in lymphoma

Recently, nontumor specific circulating DNA was shown to be elevated in a broad range of lymphomas, implicating a role as a potential biomarker. Epstein-Barr virus' (EBV) presence within a proportion of lymphomas implies EBV-DNA has potential as a lymphoma-specific disease response biomarker. However, application would be restricted to EBV-associated lymphomas. Neither detailed comparison has been performed of lymphoma-specific versus nonspecific DNA as disease response biomarkers nor have the kinetics of circulating DNA during treatment been established, and the optimal methodology remains unknown. We prospectively evaluated DNA levels and clinical response of 63 lymphoma patients. DNA was measured in paired serum, plasma, and cell samples at five predetermined time-points taken prior, during and following treatment. Both cell-free (c-f) circulating EBV-DNA (in EBV-associated lymphoma) and nonspecific c-f DNA levels (in all lymphomas) were elevated and discriminatory at presentation compared to healthy controls. Nonspecific c-f DNA was significantly associated with baseline serum lactate dehydrogenase. Within EBV-associated lymphomas at presentation, there was a strong correlation between specific and nonspecific circulating c-f DNA (r = 0.9, P < 0.0001). However, only c-f EBV-DNA correlated with clinical/radiological response. In addition, c-f EBV-DNA, and not nonspecific c-f DNA, provided an early marker of relapsed and refractory disease. Serum versus plasma, and single versus multiple-copy EBV-gene targets were equivalent. Lymphoma-specific DNA is a disease response biomarker; however, nonspecific DNA reflected neither lymphoma-specific DNA nor therapeutic response. Lymphoma disease response can be monitored by blood tests, but new lymphoma-specific biomarkers need to be identified to broaden applicability.

Serological diagnosis of Epstein-Barr virus infection: Problems and solutions

Serological tests for antibodies specific for Epstein-Barr virus (EBV) antigens are frequently used to define infection status and for the differential diagnosis of other pathogens responsible for mononucleosis syndrome. Using only three parameters [viral capsid antigen (VCA) IgG, VCA IgM and EBV nuclear antigen (EBNA)-1 IgG],it is normally possible to distinguish acute from past infection: the presence of VCA IgM and VCA IgG without EBNA-1 IgG indicates acute infection, whereas the presence of VCA IgG and EBNA-1 IgG without VCA IgM is typical of past infection. However, serological findings may sometimes be difficult to interpret as VCA IgG can be present without VCA IgM or EBNA-1 IgG in cases of acute or past infection, or all the three parameters may be detected simultaneously in the case of recent infection or during the course of reactivation. A profile of isolated EBNA-1 IgG may also create some doubts. In order to interpret these patterns correctly, it is necessary to determine IgG avidity, identify anti-EBV IgG and IgM antibodies by immunoblotting, and look for heterophile antibodies, anti-EA (D) antibodies or viral genome using molecular biology methods. These tests make it possible to define the status of the infection and solve any problems that may arise in routine laboratory practice.

[Chronic active Epstein-Barr virus infection]

The ubiquitous Epstein-Barr virus (EBV), which establishes latency after primary infection, does not cause any symptomatic diseases as long as cellular immunity is intact. In apparently immunocompetent individuals, a chronic infection can develop, and this has been called as chronic active EBV infection (CAEBV). CAEBV is characterized by chronic or recurrent infectious mononucleosis-like symptoms, such as fever, extensive lymphadenopathy, and, hepatosplenomegaly. This disease is rare but severe with high morbidity and mortality. Recently, its pathophysiology is not an infection but a clonal expansion of EBV-infected T or natural killer NK cells. In this review, I discuss our current understanding of the pathogenesis of CAEBV and summarize its clinical features, therapies, and prognosis.

EBV-associated T/NK-cell lymphoproliferative diseases in nonimmunocompromised hosts: prospective analysis of 108 cases

EBV-associated T/NK-cell lymphoproliferative disease (T/NK-LPD) is defined as a systemic illness characterized by clonal proliferation of EBV-infected T or NK cells. We prospectively enrolled 108 nonimmunocompromised patients with this disease (50 men and 58 women; median onset age, 8 years; age range, 1-50 years) evidenced by expansion of EBV(+) T/NK cells in the peripheral blood; these were of the T-cell type in 64 cases and of the NK-cell type in 44, and were clinically categorized into 4 groups: 80 cases of chronic active EBV disease, 15 of EBV-associated hemophagocytic lymphohistiocytosis, 9 of severe mosquito bite allergy, and 4 of hydroa vacciniforme. These clinical profiles were closely linked with the EBV(+) cell immunophenotypes. In a median follow-up period of 46 months, 47 patients (44%) died of severe organ complications. During the follow-up, 13 patients developed overt lymphoma or leukemia characterized by extranodal NK/T-cell lymphoma and aggressive NK-cell leukemia. Fifty-nine received hematopoietic stem cell transplantation, 66% of whom survived. Age at onset of disease (≥ 8 years) and liver dysfunction were risk factors for mortality, whereas patients who received transplantation had a better prognosis. These data depict clinical characteristics of systemic EBV(+) T/NK-LPD and provide insight into the diagnostic and therapeutic approaches for distinct disease.