Targeting EGFR with metabolically biotinylated fiber-mosaic adenovirus

Abstract

Adenovirus (Ad)-based vectors are useful gene delivery vehicles for a variety of applications. Despite their attractive properties, many in vivo applications require modulation of the viral tropism. Targeting approaches applied to adenoviral vectors included genetic modification of the viral capsid, controlled expression of the transgene and combinatorial approaches that combine two or more targeting elements in single vectors. Most of these studies confirmed successful retargeting in cell cultures, however, in vivo gains of targeted adenoviral vectors have not been widely demonstrated. We have developed a combinatorial retargeting approach utilizing metabolically biotinylated Ad, where the biotin acceptor peptide was incorporated in one of the fibers in a dual fiber viral particle resulting in metabolically biotinylated fibermosaic Ad (mBfMAd). We have utilized this vector in complex with epidermal growth factor (EGF)-Streptavidin to retarget fiber-mosaic virus to EGF receptor (EGFR) expressing cells in vitro and confirmed an increased infectivity of the retargeting complex. Most importantly, the utility of this strategy was demonstrated in vivo in two distinct animal models. In both models tested, retargeted mBfMAd demonstrated an increased ratio of gene expression in target tissues compared to the liver expression profile. Thus, metabolically biotinylated fiber-mosaic virus in combination with appropriate adapters can be successfully exploited for adenoviral retargeting strategies.

Disconnecting the Yin and Yang Relation of Epidermal Growth Factor Receptor (EGFR)-Mediated Delivery: A Fully Synthetic, EGFR-Targeted Gene Transfer System Avoiding Receptor Activation

“…**p < 0.01, standard medium versus a 1000-fold excess of free EGF, U test (Mann-Whitney). (Peng et al, 2001;Wolschek et al, 2002;Ogris et al, 2003;Pereboeva et al, 2007). In our own work, we have most often used murine EGF, which, in contrast to human EGF, does not carry any lysines in its primary amino acid sequence (Blessing et al, 2001;Wolschek et al, 2002;Ogris et al, 2003).…”

Escherichia coli expression and refolding of E/K-coil-tagged EGF generates fully bioactive EGF for diverse applications

“…This is caused by the ubiquitous cell surface expression pattern of the CAR and integrin receptors, which then leads to undesired virus uptake and gene expression in non-targeted tissues. To address this viral tropism problem, several research groups have introduced modifications and adaptor targeting-molecules to the virus fiber, which allows for the retargeting of the adenovirus to tumor cells [4][5][6].…”

Low-Affinity Neurotrophin Receptor p75 Promotes the Transduction of Targeted Lentiviral Vectors to Cholinergic Neurons of Rat Basal Forebrain

“…Owing to the superb affinity (Kd = 10 -15 M) and stability of streptavidinbiotin binding, this reaction has been used in previous studies for targeting viral and nonviral vectors, as well as other cargo, to various cell types [66][67][68][69]. It offers considerable advantages over other adaptor systems, affording outstanding stability of targeted materials.…”