Distribution, persistence and interchange of Epstein-Barr virus strains among PBMC, plasma and saliva of primary infection subjects

PLoS One. 2015 Mar 25;10(3):e0120710. doi: 10.1371/journal.pone.0120710. eCollection 2015.

Abstract

Our study aimed at investigating the distribution, persistence and interchange of viral strains among peripheral blood mononuclear cells (PBMC), plasma and saliva of primary Epstein-Barr virus (EBV) infection subjects. Twelve infectious mononucleosis (IM) patients and eight asymptomatic individuals (AS) with primary EBV infection were followed longitudinally at several time points for one year from the time of diagnosis, when blood and saliva samples were collected and separated into PBMC, plasma and saliva, representing circulating B cell, plasma and epithelial cell compartments, respectively. To survey the viral strains, genotyping assays for the natural polymorphisms in two latent EBV genes, EBNA2 and LMP1, were performed and consisted of real-time PCR on EBNA2 to distinguish type 1 and 2 viruses, fluorescent-based 30-bp typing assay on LMP1 to distinguish deletion and wild type LMP1, and fluorescent-based heteroduplex tracking assays on both EBNA2 and LMP1 to distinguish defined polymorphic variants. No discernible differences were observed between IM patients and AS. Multiple viral strains were acquired early at the start of infection. Stable persistence of dominant EBV strains in the same tissue compartment was observed throughout the longitudinal samples. LMP1-defined strains, China 1, China 2 and Mediterranean+, were the most common strains observed. EBNA2-defined groups 1 and 3e predominated the PBMC and saliva compartments. Concordance of EBNA2 and LMP1 strains between PBMC and saliva suggested ready interchange of viruses between circulating B cell and epithelial cell pools, whilst discordance of viral strains observed between plasma and PBMC/saliva indicated presence of viral pools in other undetermined tissue compartments. Taken together, the results indicated that the distribution, persistence and interchange of viral strains among the tissue compartments are more complex than those proposed by the current model of EBV life cycle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • B-Lymphocytes / virology
  • Child
  • Epithelial Cells / virology
  • Epstein-Barr Virus Infections / virology*
  • Epstein-Barr Virus Nuclear Antigens / genetics
  • Genotype
  • Herpesvirus 4, Human / genetics*
  • Humans
  • Infectious Mononucleosis / virology*
  • Leukocytes, Mononuclear / virology*
  • Longitudinal Studies
  • Plasma / virology*
  • Polymorphism, Genetic / genetics
  • Saliva / virology*
  • Viral Matrix Proteins / genetics
  • Viral Proteins / genetics

Substances

  • EBV-associated membrane antigen, Epstein-Barr virus
  • Epstein-Barr Virus Nuclear Antigens
  • Viral Matrix Proteins
  • Viral Proteins

Grants and funding

This study was funded by Research Grant Council General Research Fund (GRF) HKU763208M, Conference and Research Grant (CRCG) CRCG#104002548 and 104002068, and EBV research grant 200004525 of AKSC. HK was supported by The University of Hong Kong’s postgraduate studentship and Hotung Paediatrics Education and Research Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.