Human herpesvirus 8 DNA quantification in matched plasma and PBMCs samples of patients with HHV8-related lymphoproliferative diseases.

BACKGROUND: The quantitative evaluation of human herpesvirus 8 (HHV8) DNA is not well described in the clinical management of HHV8-related lymphoproliferative diseases. OBJECTIVES: To evaluate and to compare HHV8 viral load in different blood compartments from patients with multicentric Castleman's disease (MCD), primary effusion lymphoma (PEL) and HHV8-associated solid lymphoma (SLY) and to establish which clinical sample would be preferable for HHV8 DNA testing. STUDY DESIGN: We assessed HHV8 DNA in plasma and peripheral blood mononuclear cells (PBMCs) paired samples from 7 PEL, 8 MCD, 2 SLY HIV+ patients at the diagnosis and during the course of the illness by using a real time PCR assay. RESULTS: HHV8 viremia was always detectable at diagnosis. HHV8 DNA levels were correlated in matched pairs of samples at diagnosis and during follow-up (Spearman correlation coefficient: r=0.83, p<0.001 and r=0.73, p<0.001, respectively). The performance characteristics of the PCR assay with both materials did not show disparity by the analysis of the receiver operating characteristic (ROC) curve (X(1)(2)=0.50; p=0.48). CONCLUSIONS: Plasma or PBMCs are both adequate samples for HHV8 DNA quantification and Real time PCR provides a reliable method to estimate viral replication in patients with HHV8-related lymphoproliferations, where HHV8 viral load is a consistent feature.

No risk of maternal EBV infection for childhood leukemia.

We performed a large nested case-control study within the Finnish and Icelandic maternity cohorts to verify/falsify the association of maternal EBV infection with an increased risk of acute lymphoblastic leukemia (ALL) in the offspring found in previous studies. All hematologic malignancies diagnosed among children born during 1983 to 2006 in Finland and 1997 to 2005 in Iceland were identified through national cancer registries. For each index mother of a leukemia case, three matched control mothers with cancer-free offspring were identified. First trimester sera from 561 ALL and 144 non-ALL index mothers and from 2,105 control mothers were analyzed for antibodies to EBV viral capsid antigen (IgG and IgM), early antigen (IgG) and ZEBRA protein (IgG). Conditional logistic regression-based estimates of odds ratios and 95% confidence intervals adjusted for birth order and sib-ship size were calculated. Overall, there was no evidence of increased risk of ALL associated to EBV viral capsid antigen IgM (odds ratio, 0.9; 95% confidence interval, 0.5-1.8). The early antigen and ZEBRA antibodies (EBV reactivation markers) were also not associated with risk. The data argue against a role of EBV in ALL.

Activation of maternal Epstein-Barr virus infection and risk of acute leukemia in the offspring.

After identifying an association between maternal Epstein-Barr virus (EBV) reactivation and acute lymphoblastic leukemia (ALL), the authors analyzed a nested case-control study within Finnish and Icelandic maternity cohorts with 7 million years of follow-up to confirm EBV's role in ALL. Offspring of 550,000 mothers were followed up to age 15 years during 1975-1997 by national cancer registries to identify leukemia cases. Mothers of cases and three quarters of matched mothers of controls were identified by national population registers. First-trimester sera from mothers of 304 ALL cases and 39 non-ALL cases and from 943 mothers of controls were analyzed for antibodies to viral capsid antigen, early antigen, and EBV transactivator protein ZEBRA. Relative risk, estimated as odds ratio (95% confidence interval), was adjusted for birth order and sibship size. Combining early antigen and/or ZEBRA immunoglobulin G antibodies with the presence of viral capsid antigen immunoglobulin M antibodies did not increase the estimate for ALL risk for viral capsid antigen immunoglobulin M alone (odds ratio = 1.9, 95% confidence interval: 1.2, 3.0). Both ZEBRA immunoglobulin G antibodies and viral capsid antigen immunoglobulin M antibodies were associated with an increased risk of non-ALL in the offspring (odds ratio = 4.5, 95% confidence interval: 1.3, 16; odds ratio = 5.6, 95% confidence interval: 1.1, 29, respectively), suggesting EBV reactivation in the mothers of non-ALL cases. EBV reactivation may be associated with a proportion of childhood leukemia.

Serum antibody response to lytic and latent Epstein-Barr virus antigens in undifferentiated nasopharyngeal carcinoma patients from an area of nonendemicity.

Epstein-Barr virus (EBV)-associated undifferentiated carcinoma of the nasopharyngeal type (UCNT) is highly prevalent in southeast China, where immunoglobulin A (IgA) antibodies to viral capsid antigen and early antigen (EA) represent important markers, routinely used to assist in diagnosing this malignancy. Our study aimed at determining the EBV serological profiles of 78 UCNT patients from Italy, an area of nonendemicity for this tumor, using different assays specific for both lytic and latent EBV antigens. Serum IgA against both EA and EBNA1 and IgG and IgA to the latent membrane protein 1 (LMP1), to EA, and to the EBV transactivator ZEBRA protein were assessed. These serological responses were then evaluated according to the clinicopathologic parameters at diagnosis. The sensitivities of the IgG assays were 37.7% for LMP1, 73.6% for EA, and 61.0% for ZEBRA. EA/EBNA1 IgA reactivity was 84.4%, and a high association (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.7 to 4.0) with UCNT was observed. When EBV serological reactivities were analyzed according to the tumor, node, and metastasis staging system (TNM), a statistically significant association was found between N stage and IgG antibody rates for EA (OR, 3.6; 95% CI, 1.2 to 10.9) and ZEBRA (OR, 2.6; 95% CI, 1.2 to 5.5) and between M stage and IgG antibody rates for ZEBRA (OR, 7.1; 95% CI, 3.2 to 16.0) and LMP1 (OR, 14.0; 95% CI, 1.8 to 110.9). Our results show that no single serological marker allows the detection of all UCNT cases. EA/EBNA1 IgA represents a reliable marker for diagnosis, with a high predictive value also in areas where UCNT is not endemic, such as Italy. The analysis of serological results according to TNM classification is consistent with a progressive impairment of humoral immune response to EBV as the disease advances and may be used to improve the accuracy of diagnosis.