Semliki Forest Virus (SFV) as Vaccine-vectors
Self-replicating genetic vaccines have been developed based on the Semliki Forest virus (SFV), which have the potential to be developed as safer and more effective vaccines than the conventional genetic vaccines. Creative Biolabs has accumulated abundant experience in the successful development of SFV based vaccines. We are happy to assist you with your brilliant studies and projects.
Structure of Semliki Forest Virus
Semliki Forest virus (SFV) is a member of the Alphavirus genus, whose genome is approximately 12 kilobases in length and contains an open reading frame encoding a 5' end viral replicase and a second open reading frame encoding a 3' end structural protein. SFV is a positive-strand RNA enveloped virus. In the SFV expression vector, the open reading frame for the structural protein has been deleted and can be replaced by a heterologous gene. The SFV vector RNA can be transcribed in vitro from a plasmid containing the sequence downstream of its SP6 promoter and transfected into cells where it can be translated to produce a replicase. This protein will use genomic RNA as a template to synthesize negative strand RNA, which in turn will serve as a template for amplifying the viral genome. However, they cannot multiply because there is no gene encoding structural proteins in the replicon of the package. Expression of the alphavirus vector is transient as apoptosis is induced in the infected cells. Vectors based on SFV have been widely used in vivo and in vitro to express heterologous genes in animal cells. SFV recombinant particles have the potential to be developed as safe vaccines due to lack of persistence and effective immune stimulation.
Semliki Forest Virus as Vaccine-vectors
Semliki Forest virus (SFV)-based vector has broad tropism and is capable of infecting cells from different sources, which does not have pre-existing immunity against vectors in most individuals, and does not express vector structural proteins. SFV vectors have been shown to successfully induce humoral and cell-mediated immunity against several diseases. This powerful protective effect and other features make the SFV vector a potential candidate for development of a prototype vaccine. In the SFV vector system, the structural protein gene is replaced by a foreign gene which is expressed in vivo in a manner similar to the viral structural protein gene. The structural proteins required to package the viral particles expressing the foreign protein are provided in reverse by the helper RNA. To further enhance the biosafety of the system, split helper RNA has been developed which prevents the production of replication-defective viruses. In addition, mutations in capsid helper cells prevent the production of infectious viruses by eliminating self-cleaving ability.
These vaccines are based on the genome of these single-stranded RNA viruses and drive their own replication, resulting in high levels of transient expression of the cloned genes in the transfected cells. If you are interested in our services, please contact us to get more information or directly send us an online inquiry.
All of our products can only be used for research purposes. These vaccine ingredients CANNOT be used directly on humans or animals.
