Vaccinia Viral Vector Development Service
Gene therapy is a promising approach, but it requires improving gene transduction in clinical trials. The vaccinia virus (VACV or VV) is a large and complex enveloped virus which is a member of the Poxviridae family, widely used for high-level cytoplasmatic expression of transgenes. The vaccinia virus has been successfully used as a vaccine to eradicate smallpox. Besides, it also serves as a tool to transfer genes to biological tissues. Creative Biolabs provides highly attenuated, host-restricted, non- or poorly replicating vaccinia virus strains covering multiple gene delivery demands in gene therapy all over the world.
Vaccinia Viral Vector Construction
The vaccinia virus has a linear dsDNA genome of approximately 190 kb which can generously accommodate more than 30 kb of foreign DNA. Foreign genes can be integrated into the viral genome stably, resulting in efficient and long-term gene expression. Re-engineered attenuated vaccinia viruses created from different strains have proved to be non-toxic and safe in humans. The deletion of the viral genes of thymidine kinase (TK) and vaccinia growth factors (VGF) results in enhanced tumor targeting activity and complete retaining of their replication efficiency in cancer cells. Vaccinia viral vectors have been engineered to express various immunizing antigens and used for cancer therapy, including breast cancer, colorectal cancer, glioblastoma, lung cancer, pancreatic cancer and prostate cancer.
Modified Vaccinia Ankara（MVA）Vector
The Modified Vaccinia Ankara (MVA) virus is a highly attenuated strain of vaccinia virus, derived from vaccinia strain Ankara by over 570 passages in chicken embryo fibroblast cells (CEF) with a loss of about 10% of the vaccinia genome. Due to the high safety of the attenuated phenotype, MVA is widely used for clinical research. Moreover, MVA has the ability to deliver antigens in a highly immunogenic way, which makes it a proper vaccine vector.
Fig.1 Recombinant MVA vector construction for gene therapy
NYVAC Vector
The NYVAC vector is a highly attenuated strain of vaccinia virus which was derived from a plaque-cloned isolate of the Copenhagen vaccinia vaccine strain with the deletion of 18 orfs that contain virulence factors and human host range replication proteins. NYVAC cannot replicate in human cells, either.
ALVAC Vector
ALVAC is an attenuated canarypox virus vector which was derived from a plaque-cloned virus of Kanapox. The ALVAC vector replicates only in avian species and not in mammalian cells, thus being used as a ubiquitous vector for the development of several vaccines for animals (such as horses) and humans.
TROVAC Vector
TROVAC is an attenuated fowlpox virus vector which was derived from a plaque-cloned FP-1 vaccine strain. Just like ALVAC, TROVAC do not grow in mammalian cells.
Others Vectors
The PANVAC system comprises recombinant vaccinia and fowlpox viruses, carrying the tumor-associated antigens epithelial MUC-1, the carcinomebryonic antigen (CEA) as well as T cell stimulatory molecules. And a novel cowpox virus (CPXV) vector was engineered with a deletion of the tk gene and insertion of the suicide gene FCU1.
Features
- Broad host range
- High insertion capacity for multiple foreign genes
Creative Biolabs is devoted to improving the vaccinia viral vector's safety and reducing the risk of cytopathic effects for the gene therapy research. We offer one-stop services for your items about the design and construction of the proper vectors for gene delivery. Please feel free to contact us and we look forward to working with you.
References
- Kenneth Lundstrom. (2018). Viral Vectors in Gene Therapy. Diseases, 6(2): 42.
- Altenburg, A.; et al. (2014). Modified vaccinia virus ankara (MVA) as production platform for vaccines against influenza and other viral respiratory diseases. Viruses, 6(7), 2735-2761.
