Dennis M Dogbey

Conference 2022 Pre-recorded Presentation

Video title

Modulation of engineered targeted viral vectors for cancer immunotherapy

Authors and Affiliations

Dennis M. Dogbey1, Alex O. Akinrinmade1, Stefan Barth 1,2

1. Medical Biotechnology and Immunotherapy Research Unit, IDM.
2. SARChl in Cancer Biotechnology, Division of Chemical and System Biology, IBMS, UCT.



Gene and or drug delivery systems are mechanistic constructs that deliver therapeutics to diseased cells. These technological systems either by viral or non-viral platforms make up an integral part of emerging cancer gene therapy and immunotherapy therapeutics. Though several viral vectors have been utilised for the above-mentioned purpose, adeno-associated viruses (AAV) have dominated and are largely preferred due to its small and easy to manipulate genome size, less immunogenicity as well as poor disease-causing abilities. However, challenges of non-specificity, off-target organ transduction, packaging and purification of viral particles have bedevilled approval of AAV-based therapies currently in clinical trials.


: Recombinant AAV plasmids will be cloned using molecular techniques of polymerase chain reaction splicing by overlap extension to introduce and amplify gene segments displaying the molecules for site-directed bioconjugation. rAAVs plasmid will be transfected in HEK 293 T cells, packaged, harvested, and purified. Purified rAAV particles will be modified by EGFR- and EpCAM-targeting recombinant antibody fragments. Targeted binding to EGFR and EpCAM surface antigens on tumour cell lines will be determined by eGFP encoded AAV cassette and visualized under confocal microscopy.


Preliminary data from our lab and elsewhere have demonstrated the efficacy of this promising approach to cancer therapy. Here we aim to establish and evaluate a targeted viral vector delivery system which can readily to EGFR- and EpCAM-positive cells by antibody engineering


Challenges affecting gene delivery platforms is predominantly marked by non-specificity, poor production yield and immunogenicity of viral vectors. Though, non-viral gene delivery platforms are preferred due non-immunogenicity, they are bedevilled by poor transduction of target cells. Here, the focus is to develop a targeted viral gene delivery system based on protein and antibody engineering technology already existing in our lab.