Expression of Epstein-Barr virus proteins and their detection by IgG antibodies

Author

Alyssa Rosek, Southern Illinois University CarbondaleFollow

Date of Award

12-1-2018

Degree Name

Master of Science

Department

Molecular Biology Microbiology and Biochemistry

First Advisor

Ran, Sophia

Abstract

Epstein-Barr virus, or EBV, is a human herpesvirus that is nearly universally present in most of the human population. The infection rate in adults is quickly approaching an astonishing 95% worldwide. While the most common clinical manifestation of EBV infection is infectious mononucleosis, there are multiple malignancies strongly associated with the virus, such as nasopharyngeal carcinoma (NPC). A contemporary problem in public health is the scarcity of markers to predict the development of EBV-associated malignancies, which prevents a possible cure or a suitable treatment. Of the approximately 85 proteins that the virus expresses, EBV serological tests rely on detection of antibodies against only three antigens: BFRF3 (viral capsid antigen or VCA), BMRF1 (early antigen or EA), and BKRF1 (nuclear antigen or NA). Antibodies against two of these antigens, VCA and NA, are produced by almost all EBV carriers for their entire lifetime, and so detection of these antibodies can make it difficult to differentiate between non-cancerous EBV carriers and EBV-associated cancer patients. To address this problem, the project aimed to identify a set of markers to diagnose NPC and treat it. To test this, 3 EBV genes were cloned with a 3X FLAG-tag into a mammalian expression vector, then expressed and detected by immunoblotting with a monoclonal FLAG antibody and each of the 9 human serum samples used in this study. Our results were generally inconclusive, and further studies are warranted to explore possible diagnostic and prognostic biomarkers.