To date, species C Ad5 has dominated the field of Ad based therapeutics. However, in recent years limitations to Ad5 have emerged, including pre-existing immunity, blood factor affinity, and off target effects. To combat these issues, a variety of laboratories have explored the other Ad serotypes as potential therapeutics. However, much of our understanding of the biology of adenoviruses (Ads) is extrapolated from human species C Ads 2 and 5. Greater understanding of the biology of alternative Ads as their use expands, will help to avoid pitfalls, and inform their use.
Our laboratory has identified species D Ad 26 as promising oncolytic virus against B cell cancer. This thesis is directed at characterizing the biology and towards making species D virus Ad26 into a useful therapeutic agent against B cell malignancies.
To gain a better understanding of differences in Ad biology between distinct species, the life cycles of Ad26 was compared to Species C Ad6 in human A549 lung cells in vitro. In these cells, both Ad6 and Ad26 infection gave rise to similar genome replication kinetics. However, when evaluating transcriptional output from the cell, Ad6 had greater transcripts accounting for 14-17% of all transcripts compared to 3-13% for Ad26. Specific analysis of viral gene expression by RT-qPCR and NGS revealed unique differences in E1 and E3 regions for the two Ads. Further analysis cellular effects mediated by E3 revealed Ad6 was markedly more effective at suppressing MHC I display on the cell surface and in evading TRAIL-mediated apoptosis than Ad26.
Further analysis of the importance of E3 genes was examined in a murine model of B cell lymphoma (A20). Multiple Ad26 viruses with varying deletions in the E3 region were tested. Studies revealed consistent efficacy, though modest, when tumors were treated with Ad26 viruses with a deletion in E3-14.7k or E3-49k. Importantly, studies on A20 cells in vitro revealed no viral replication, or even transduction of the cells. Thus leaving us to hypothesize that Ad26 efficacy in this model is likely dependent on immune modulation in the tumor microenvironment. As such, follow up studies and further characterization of the immune responses elicited or controlled by the different E3 viruses will be of great importance.
Understanding these differences expands the knowledge of alternative Ad species and informs our development towards a viable Ad26 cancer therapeutic.
|Advisor:||Barry, Michael A.|
|Commitee:||Ikeda, Yasuhiro, Jelinek, Diane F., Kaufmann, Scott H., Russell, Stephen J.|
|School:||College of Medicine - Mayo Clinic|
|Department:||Virology and Gene Therapy|
|School Location:||United States -- Minnesota|
|Source:||DAI-B 77/10(E), Dissertation Abstracts International|
|Subjects:||Molecular biology, Bioinformatics, Virology|
|Keywords:||Adenovirus, B cell lymphoma, Cancer therapy, Gene expression, Immune modulation, Rna-seq|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be