Date of Graduation

Spring 5-17-2015

Document Type


Degree Name

Master of Science in Biology


College of Arts and Sciences



First Advisor

Juliet V. Spencer

Second Advisor

James Sikes

Third Advisor

Mary Jane Niles


Human cytomegalovirus (HCMV) is widespread in the general population and can establish lifelong latency with expression of a limited subset of viral genes. The UL111A gene is expressed during both lytic and latent infection, and at least two protein isoforms are produced. During lytic infection, the full length transcript yields cmvIL-10, a potent immunosuppressive viral ortholog of human IL-10 (hIL-10). Alternative splicing of the UL111A transcript yields a truncated protein, LAcmvIL-10, which is expressed during both lytic and latent infection but with a limited range of immunosuppressive functions. The two viral cytokines, collectively termed viral IL-10 (vIL-10), are identical in amino acid sequence through C127, then divergent at the C-terminus. A sensitive and specific ELISA was developed to detect both vIL-10 isoforms in supernatants from transfected and virus-infected cells. Specimens from healthy blood donors were tested for HCMV serostatus and vIL-10 levels. Of the thirty seropositive donors, twenty had detectable plasma vIL-10 levels while ten had no detectable vIL-10 levels. The results suggest that the custom vIL-10 ELISA was effective in detecting plasma vIL-10 and that vIL-10 is produced at measurable levels in healthy adults. Ultimately, these findings may provide a snapshot of viral protein expression during latency and help characterize the interplay between the two isoforms of vIL-10 with respect to productive and latent infection.