A Recombinant E1-Deleted Canine Adenoviral Vector Capable of Transduction and Expression of a Transgene in Human-Derived Cells andIn Vivo

Abstract

Human adenovirus (HAV) serotypes 2 and 5 are commonly used as vector backbones for adenovirus-mediated gene transfer. However, HAVs were chosen as a backbone for the vectors for historical reasons and have a number of significant disadvantages when used as a shuttle for gene transfer in humans. As an initial trial to circumvent some of the shortcomings of HAV vectors, we have produced an E1-deleted canine adenovirus type 2 (CAV-2) vector for gene transfer. Initially, we demonstrated that CAV-2 undergoes an abortive viral cycle in a wide range of human-derived cell lines. Second, we assayed human sera containing HAV-5 neutralizing antibodies for their ability to inhibit CAV-2-induced plaques on permissive cells. In the cohort tested, our data demonstrate that the humoral response directed against HAV-5 does not inhibit CAV-2 plaque formation in the majority of cases. Canine cell lines expressing the E1 region of CAV-2 were generated and characterized. A recombinant CAV vector (CAVRSVbetagal) deleted in the E1 region and harboring lacZ was constructed. We show that CAVRSVbetagal is able to transduce and direct expression of the transgene in vitro in a variety of mammalian cells, most notably primary human-derived cells. In addition, gene transfer is demonstrated in vivo using chick embryos.

Immunocompetent mouse model of breast cancer for preclinical testing of EphA2-targeted therapy

“…[25][26][27][28][29][30] The immunocompetent breast cancer mouse model described in this paper could be a useful tool for testing circumvention of vector-specific immunity by alternative administration of human and non-human adenoviral vectors targeting EphA2. It will also offer an excellent model for preclinical testing of other gene therapy approaches where the vector entry into breast cancer cells is targeted through EphA2-specific interactions.…”

Immunity to adenovirus and adeno-associated viral vectors: implications for gene therapy

“…It was demonstrated that almost all subjects tested (from North America) have immunoglobulins to adenovirus type 5 of which 55% were neutralizing. 15 In addition to adenovirus type 5, serotypes 2, 7 and 17 of human adenovirus 16,17 and animal adenoviruses 18,19 have been used as vectors for studies of gene transfer. It is hypothesized that neutralizing antibodies directed against the knob and fiber domains of the viral capsid play a significant role in blocking infection.…”

Adenoviral Vectors: Potential and Challenges as a Gene Delivery System

“…The nonhuman AdV do not cause disease in humans and are not neutralized by the HAdV-specific neutralizing antibodies (Moffatt et al, 2000;Sharma et al, 2010;Singh et al, 2008). In addition, nonhuman AdV vectors have been shown to transduce human cells in culture and express transgene (Bangari et al, 2005;Bangari & Mittal, 2004;Farina et al, 2001;Klonjkowski et al, 1997;Mittal et al, 1995;Rasmussen et al, 1999). Advances in the past decade signify the potential of nonhuman AdV vectors as effective gene delivery vehicles without any significant toxicity and interference from pre-existing immunity.…”