Ad/AAV Hybrid Vectors Construction
Recently, studies have shown that inverted repeat sequences inserted into the genome of the first-generation adenovirus (Ad) vector mediate precise genomic rearrangements, resulting in the lack of all viral genes in the vector genome that are efficiently packaged into the functional Ad capsid. As a leader in this field, Creative Biolabs has been able to provide high-quality services for the construction of Ad/adeno-associated virus (AAV) hybrid vectors by virtue of our extensive experience in viral vectors, and to better benefit the field of gene therapy.
Ad/AAV Hybrid Vector for Gene Therapy
Successful gene therapy depends on the "bell and whistle" of transgene delivery vectors. Ideally, these vectors should not only transfer a large target gene to the target cell, but also permanently express the gene. It is becoming more and more obvious that none of the vectors currently being developed can meet the needs of human gene therapy. With the development of high titer virus production methods, AAV vectors are more and more widely used in gene therapy. It is a protein shell that surrounds and protects a small single-stranded DNA genome of about 4.8 kb. AAV belongs to the parvovirus family and mainly depends on the co-infection of adenovirus for replication. In current viral vectors, Ad vectors have the ability to transfer a large DNA fragment (~150 kb) into cells, while AAV vectors can integrate the gene into mammalian cell genome for long-term gene expression. Using these two viral vectors to develop a hybrid transmission system containing their advantages has become the research goal of many research groups, which greatly promotes the development of gene therapy vectors.
Figure 1. Schematic of AAV as a gene therapy vector. (Lotfinia, 2019)
Ad/AAV Hybrid Vectors Development at Creative Biolabs
Gene transfer vectors are widely used in preclinical research of animal models of diseases, and are the research tools to realize gene transfer in vivo and in vitro. We are committed to providing customizable vectors for researchers with low cost and high quality in a short time to promote the development of gene therapy. The engineering of hybrid vectors makes it possible to combine the advantages of different viral vectors. As an expert in the field of viral vectors, we constructed a chimeric Ad/AAV vector containing a first-generation Ad vector and a reporter gene flanked by the inverted terminal repeat (ITR) sequences of AAV to achieve chromosomal integration. In transduced cell lines, randomly integrated reporter genes showed stable long-term expression. In addition, we combine the package signal from the helper-dependent adenoviral (HDAd) with the integrated signal from the AAV. Through Cre/LoxP mediated recombination (which is an integral experimental tool for mammalian genetics and cell biology), the hybrid vectors can be packaged into virus particles similar to Ads, which greatly reduces the infection rate of HDAd vectors. This hybrid has about 14 kB of transgenic ability and can adapt to the most common genes.
Figure 2. Diagram of rescue and amplification of high-capacity AAV/Ad hybrid vectors. (Gonçalves, 2002)
Features of Our Ad/AAV Hybrid Vector Construction Service
- Providing customized services for each step of the Ad/AAV hybrid vectors construction process
- Providing short-hairpin RNA (shRNA) screening and validation services for cells
- Good quality control
If you are interested in our Ad/AAV hybrid vector construction services, please contact us and we will be happy to assist you.
References
- Lotfinia, M.; et al. (2019). Adeno-associated virus as a gene therapy vector: strategies to neutralize the neutralizing antibodies. Clinical and experimental medicine. 1-10.
- Gonçalves, M.A.F.V.; et al. (2002). Efficient generation and amplification of high-capacity adeno-associated virus/adenovirus hybrid vectors. Journal of virology. 76(21): 10734-10744.
