Epstein-Barr virus (EBV) is a ubiquitous herpes virus recognized as the cause of infectious mononucleosis, and a variety of human neoplasia including nasopharyngeal carcinoma, thymic carcinoma, and lymphoma. This virus is capable of establishing latency in B- lymphocytes and epithelial cells. It is a potent polyclonal B cell activator, and incites an intense T-cell mediated immune response. EBV has recently been associated with several ocular inflammatory disorders including aqueous tear deficiency, keratitis, uveitis, and retinitis. With the exception of demonstrating EBV antigens in the lacrimal glands of tear deficient patients, the causal relationship of EBV to these ocular inflammatory diseases has been based on serologic evidence of acute or chronic infection. Unlike other herpes viruses which cause disease by viral replication, EBV is most often found in a latent, non-replicative state. Diagnosis of infection is based on demonstrating viral genomes. Conventional techniques such as in-situ hybridization of Southern blot analysis lack sufficient sensitivity to detect DNA in minute specimens, such as those obtained from the eye and adnexae. A novel method of DNA amplification, polymerase chain reaction (PCR), has recently been introduced. PCR can specifically amplify viral genome up to 1 x 107 times in several hours. PCR has been utilized to detect Papilloma virus and HIV infections. The principal investigator plans to apply the PCR to detect EBV DNA within ocular tissue and fluid. The initial phase of this project will involve refining the technique to detect DNA in EBV- infected lymphoblastoid cells. Following the establishment of positive controls, fresh human autopsy tissue including conjunctiva, cornea, uvea, retina, and lacrimal gland will be surveyed for the presence of DNA. PCR will also be used to examine paraffin embedded pathology specimens. This work is essential to establish the efficacy of PCR as a diagnostic tool for future clinical and laboratory investigation of EBV as an inciting factor for ocular inflammation.
