Improving Protein Translation in an Attenuated Vaccinia Virus System using Translation Enhancing Elements

Developing effective and safe vaccines without the necessity for booster vaccinations is essential to providing lasting immunity for global populations. The vaccinia virus, which was successfully used as a vaccine in the elimination of small pox, is an attractive agent for vaccine development given the ease with which it can be modified. One major drawback to vaccinia virus use however, is the potential for harmful systemic vaccinia reactions. To improve safety, the virus used as an immunogen can be attenuated. Yet, while attenuation can improve safety concerns, it also reduces the efficacy of the vaccine. This reduction is largely attributed to a decreased amount of protein delivered to the immune system. In an effort to improve vaccines exhibiting less immunogenicity, we aim to increase protein translation in an attenuated virus system by using translation enhancing elements (TEEs) previously discovered from the human genome. One in particular, termed 5d5, acts as a vaccinia virus promoter and a TEE. Here we explore combining other TEEs demonstrating high levels of activity with 5d5 to determine whether we can increase protein expression in an attenuated virus system. The effect of each combination on protein expression is measured by transfection/infection assays using luciferase based plasmids. We use wild‐type and attenuated vaccinia virus strains (Copenhagen and NYVAC, respectively) in our model system to compare luciferase expression levels between the two for each of the constructs. Although we did not find any significant increases in translation when combining TEEs with 5d5, we did show for the first time at least a 2‐fold increase in translation when using 5d5 in the NYVAC system when compared to expression when unmodified virus is used. Support or Funding Information Midwestern University intramural funding