330. Genetic Modification To Achieve Targeting of Adenoviral Vectors To Malignant Cells of Lymphocyte Origin
Year: 2015
Type: article
Abstract: Hematologic malignancies comprise tumors that affect three related cellular compartments; blood, bone marrow and lymphatics Gene therapy is an outstanding approach to treat hematological malignancies as the molecular basis of these disorders is increasingly understood. Therapeutic genes are available and alternative therapies are often lacking efficiency however, the, systemic nature of hematologic malignancies requires selective tumor targeting. Recombinant Adenoviral (Ad) vectors derived from human serotype 2 and 5, are currently, the most common vehicle for efficient in vivo transgene delivery and account for 23.8% of nearly 1700 clinical trials that were conducted by using both viral and non-viral vectors. Initial binding of virus fiber knob to the cell surface coxsackie-adenovirus receptor (CAR) followed by secondary binding with avb3/5 integrins on the cell surface are the prerequisites for successful viral internalization to the target cell. However, several studies have shown that cells of lymphocyte origin (B cell, T cell, NK cells etc.) are poorly infected by adenovirus due to the paucity of both CAR and integrins. Hence, retargeted adenovirus must be developed that will bypass both CAR and integrin requirements. Our goal is to explore mechanisms to target lymphocytes at the level of transduction (or infection). Transductional targeting provides improved gene transfer into cancerous cell and spares normal cells. This is typically accomplished through surface modification of the gene delivery vehicle to enhance specific interactions with cancer cell membrane proteins. We hypothesize that, transductional targeting of adenovirus by utilizing anti-Interleukin-2-receptor (IL-2R) antibody to target cell surface Il-2R will allow us to conduct CAR and integrin independent cell specific targeting of adenovirus to malignant lymphocytes. To accomplish this goal, the sequences of canine, human and murine IL-2 and IL-2R were compared to each other. This data shows that human and canine IL-2 and IL-2R may cross react whereas murine IL-2 has diverged significantly. Based on these results, canine IL-2 and IL-2R were cloned, followed by sub-cloning these constructs, along with the ectodomain of IL-2R (Ecto-IL-2R), into eukaryotic expression vectors. Antibody constructs will be generated by immunizing with Ecto-IL-2R. The DNA encoding these antibodies will be cloned and inserted into the adenoviral fiber gene to allow knob-scIL-2RAb fusion proteins to be produced.
Source: Molecular Therapy
Institution: Auburn University
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
OpenAlex ID: W2563126548