Specimen Required

Serology: Suitable specimens are individual samples (human sera or EDTA/heparinized/citrated plasma) obtained by standard laboratory techniques.

Blood

Container/Tube: Serum separator (SST) or Plain Red-top tube(s)

Specimen Volume: 5 mL of whole blood

Specimen Minimum Volume

0.3 mL

Transport Temperature

*The samples should be stored for not more than 2 days at 2-8^°C.

**For longer delay, freeze at -20^°C or below and transport on dry ice.

Reject Due To

Useful For

These tests are recommended only when a mononucleosis screening procedure is negative and infectious mononucleosis or a complication of Epstein-Barr virus infection is suspected

Clinical Information

Epstein-Barr virus is a ubiquitous human herpes virus. Infection with EBV is common, worldwide in distribution, and largely subclinical in early childhood. EBV has been established as the causative agent of heterophile-positive infectious mononucleosis, which occurs most frequently in late adolescence or early adulthood. In addition, EBV is causally associated with the development of malignant diseases, including Burkitt’s lymphoma, lymphoproliferative disease, Hodgkin’s lymphoma, primary central nervous system (CNS) lymphomas in acquired immunodeficiency syndrome (AIDS), and nasopharyngeal carcinoma based on seroepidemiologic data and the detection of EBV genomes in these tumors.

Infection of the target cells leads to two forms of viral cycles: 1) latent, nonproductive and 2) productive, replicative infections. In both cycles, one of the earliest antigens expressed is lymphocyte-detected membrane antigen, a cell-surface antigen recognized by T-cells. It has been well established that most individuals exposed to EBV develop a heterophile antibody response. Expression of EBNA-1 either follows or parallels membrane antigen at 12 to 24 hours post infection. EBNA-1 is found as nonstructural, intranuclear antigen(s), present in all EBV-transformed cell lines as in tumors from Burkitt’s and nasopharyngeal carcinoma patients. In the fully productive, replicative cycle, the synthesis of antigen follows EBNA-1. Antibody levels of EBNA-1 IgG, are diagnostic in determining acute and convalescent stages in IM. IgG antibodies to EBNA-1 are rarely present in acute IM and rise during convalescence. They will rise to a plateau level in three months to a year and will normally persist for life. The viral capsid antigen complex (VCA) appears late in the replicative cycle and antibodies to VCA are detectable in the early course of disease. The levels of antibody rise early and peak after 3-4 weeks, then decline and persist at low levels for life.

The Epstein-Barr virus (EBV), also known as human herpesvirus 4, belongs to the subfamily Gammaherpesvirinae in the Herpesviridae family. EBV has the morphology of a herpesvirus, with 162 capsomeres in icosahedral arrangement surrounded by a lipid-rich envelope. EBV primarily infects B cells, which carry the receptor for EBV, the CD21 complement receptor. It has the ability to transform precursor and mature human B lymphocytes to lymphoblastoid cell lines. B cells are the site of latency, but epithelial cells, not expressing the receptor, are the main producers of progeny virus. Also monocytes may be productively infected by EBV, and the infection may affect the virus-host interaction.

Reference Values

VCA IgM: NONREACTIVE

VCA IgG: NONREACTIVE

EBNA-1 IgG: NONREACTIVE

Interpretation

Clinical Reference

Johannsen, E. C., and Kaye, K. M. 2010. Epstein-Barr Virus (Infectious Mononucleosis, Epstein-Barr Virus – Associated Malignant Diseases, and Other Diseases), p. 1989-2010. In Mandell, D., Bennett, J. E., and Dolin, R. Principles and practice of infectious diseases, 7^th ed., vol. 2. Churchill Livingstone, Elsevier, Philadelphia, PA.

Linde, A., and Falk, K. I. 2007. Epstein-Barr Virus, p. 1564-1573. In Murray, P. R., Baron, E. J., Jorgensen, J. H., Landry, M. L., and Pfaller, M. A. Manual of Clinical Microbiology, 9^th ed., vol. 2. ASM Press, American Society for Microbiology, Washington, DC.

Gärtner, B. 2011. Varicella-Zoster Virus, p. 1575-1584. In Versalovic, J., Carroll, K. C., Funke, G., Jorgensen, J, H., Landry, M. L., and Warnock, D, W. Manual of Clinical Microbiology, 10^th ed., vol. 2. ASM Press, American Society for Microbiology, Washington, DC.

EBV Antibody Profile

Method Description

Enzyme-Linked Immunosorbent Assays (ELISA) rely on the ability of biological materials (i.e.,antigens) to adsorb to plastic surfaces such as polystyrene (solid phase). When antigens bound to the solid phase are brought into contact with a patient’s serum, antigen specific antibody, if present, will bind to the antigen on the solid phase forming antigen antibody complexes. Excess antibody is removed by washing. This is followed by the addition of goat anti-human IgG/IgM conjugated with horseradish peroxidase which then binds to the antibody-antigen complexes. The excess conjugate is removed by washing, followed by the addition of Chromogen/Substrate, tetramethylbenzidine (TMB). If specific antibody to the antigen is present in the patient’s serum, a blue color develops. When the enzymatic reaction is stopped with 1N H₂SO₄, the contents of the wells turn yellow. The color, which is indicative of the concentration of antibody in the serum, can be read on a suitable spectrophotometer or ELISA microwell plate reader. The sensitivity, specificity, and reproducibility of ELISAs can be comparable to other serological tests for antibody, such as immunofluorescence, complement fixation, hemagglutination and radioimmunoassay.

Performing Laboratory Location

Newfoundland & Labrador Public Health Laboratory

St. John’s