Custom Viral Vector Production Services
Gene therapy is a new technology that involves modifying an individual's genes to treat a specific disease. The efficacy of gene therapy depends heavily on the development of an efficient delivery system that can safely transport the modified genes into the patient's cells. Among the popular delivery systems, viral vectors modified to lose their pathogenicity are widely used. These vectors have naturally high transduction efficiency and stable expression and are ideal for gene delivery. Creative Biolabs has a wealth of experience in producing various viruses, including Lentiviral Vectors, Adenovirus Vectors, Adeno-associated Virus Vectors, Herpes Simplex Virus Vectors, and Vaccinia Viral Vectors. Our proficiency in the creation of numerous viruses enables us to provide premium viral vectors that are tailored to the needs of our customers.
Fig.1 Viral vector production process.
Viral Vector Production
Different culture systems are available for the creation of viral vectors depending on the quantity of the viral vector to be produced as well as the cell system employed. In general, adenoviral, AAV, and LV vectors are produced using a discontinuous mode after induction of the production. This induction is carried out either by infecting the cells with one or more viruses that are capable of carrying out the necessary tasks or by transfecting the cells with plasmids that both provide the helper functions and the vector construct. Cells can either be cultivated adherently or in suspension, depending on the growth properties of the producing cells. We have established multiple stable and efficient cell banks and high-yield production systems to meet different virus production needs, such as HEK293 cells, BHK cells, Vero cells, BSC-1 cells, among which HEK293 cells are used for the production of lentivirus, adenovirus, and adeno-associated virus, BHK cells and Vero cells are used for the production of Herpes Simplex Virus, and BSC-1 cells are mainly used for the production of Vaccinia Viral.
Viral Vector Purification
Virus purification is a key step to ensure the quality, safety, and effectiveness of the virus. It refers to the process of removing all other substances (such as bacteria, and fungi.) from a virus sample, leaving only the virus. Here are some common virus purification technologies:
1. Precipitation with Additives:
This method is frequently used to concentrate viral particles while manufacturing traditional viral vaccines. The advantage of it is that viral pellets can be promptly and easily produced at low centrifugation rates after the treatment. Both polymers (such as PEG) and salts have been used as additives to promote the precipitation of virus particles.
2. Density Gradient Ultracentrifugation:
This method uses variations in size, shape, and density to differentiate virions from other pollutants in solution. Using a thick substance in solution, gradients are created. The two chemicals that generate gradients most frequently employed for virus purification are cesium chloride (CsCl) and sucrose.
3. Ion Exchange Chromatography:
Biomolecules differ from one another in their net surface charge. IEX exploits these differences to separate viruses from contaminating molecules present in vector stocks.
4. Affinity Chromatography:
This approach separates biomolecules based on a particular interaction between a target molecule and a ligand coupled to a chromatography support.
Different purification methods determine the quality of the virus, which in turn determines the scope of use of the virus. If the virus is used in in vitro gene transfer experiments, a more economical purification method is generally used. In contrast, viral vector preparations that will be used in gene transfer experiments ex vivo or in vivo usually need to undergo a series of stringent purification steps to increase the potency and safety of the final product. Our purifying procedures are continuously improved to reduce yield loss and maintain purity. Additionally, we offer unique virus purification services to aid client research.
SERVICES
Creative Biolabs can provide construction and packaging services for different viral vectors, as well as purification and quality control services Our flexible production system and strict quality control standards ensure that we provide customers with high-quality customized services. Please feel free to contact us, if you need additional details, and one of our scientists will go into more detail about your project.
