Targeting of Adenovirus Vectors to Breast Cancer Mediated by Soluble Receptor-Ligand Fusion Proteins
Abstract
The use of adenovirus (Ad) vectors for cancer gene therapy applications is currently limited due to the broad viral tropism associated with the widespread expression of primary coxsackievirus and adenovirus receptor (CAR) in human tissues. To confer Ad targeting capability to relevant cell types we have proposed the use of soluble CAR ectodomain (sCAR) fused with ligand to block CAR-mediated tropism and simultaneously achieve infection through a novel receptor overexpressed on target cells. To target Ad vectors to breast cancer cell types we produced bispecific proteins containing sCAR and either alpha(v)-integrin binding RGD-4C or NCR peptide motif possessing high potential for bacteriophage targeting to human breast cancer xenografts in mice. Specifically, we designed gene encoding sCAR, purification tag, phage T4 fibritin polypeptide, hinge region and site for cloning of ligand sequences. Incorporation of fibritin polypeptide provided trimerization of sCAR-fusion proteins that resulted in augmented affinity to Ad fiber knob domain and increased ability to block CAR-mediated Ad infection compared to monomeric sCAR protein. We also demonstrated that most of breast cancer cell lines tested display low CAR and high levels of alpha(v)-integrins. Thus, utilization of constructed trimeric sCAR-ligand proteins for Ad targeting may augment Ad vectors potency for breast cancer treatment. 1
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2001
- Accession Number
- ADA394358
Entities
People
- Igor P. Dmitriev
Organizations
- University of Alabama