Overcoming Deficiencies in Gene Therapy Delivery with Chimeric and Inducible Vectors
DOI:
https://doi.org/10.58445/rars.3176Keywords:
Viral Vectors, Bioengineering, Chimeric, Chimeric Viral Vectors, Inducible, Inducible Viral Vectors, AAV, Adenovirus, Lentivirus, Gene TherapyAbstract
Viral gene therapy intends to bring genetic materials to the cell using a modified virus. This delivery system is called a viral vector. The viral vector often takes the property of the virus in regards to delivery, so the choice of virus leads to various outputs. Viruses differ from one another depending on their tropism, hitting certain tissues better than others; immunogenicity; and size. This review compiles evidence of recent innovations in the delivery of gene therapy using viral vectors with a specific emphasis on inducible and chimeric viral vectors that address long-standing limitations of traditional viral vectors. Conventional viral vectors, despite being the current standard for gene therapy delivery, pose risks and have significant flaws. Many elicit severe immunogenic responses and often hit unintended cells and tissues. This review discusses two new categories of viral vectors: chimeric vectors, which are a combination of two or more vectors, and inducible viral vectors, which use spacio-temporal awareness to improve efficiency and targeting. Chimeric vectors adopt key features from multiple different vectors to create a hybrid. These hybrid vectors can target new cell types, lower immunogenicity, and make downstream purification easier.Meanwhile, inducible vectors rely on external stimuli to dictate their expression. Inducers include small molecules, RNA, and light. While concerns remain around scalability of these therapies, the next level targeting capabilities make them promising for further use in the gene therapy space.
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