Viral vector

microbiology,biotechnology etc

1. VIRAL VECTOR Presented by; Manka Mary 1 st M.Sc.Microbiology

2. INTRODUCTION Vector is a vehicle used to transfer the genetic material into a target cell.

3. Viral vectors are tools used by molecular biologist to deliver genetic material into cells.

4. Uses of viral vectors Virus are obligate intracellular parasites. Very efficient at transferring viral DNA into host cells. Specific target cells depending on the viral attachment proteins’ Gene replacement non essential genes of virus are deleted and exogenous genes are inserted.

5. Properties of Viral Vectors Safety: Deletion of the viral genome critical for viral replication e.g helper virus . Low Toxicity . Stability: Some viruses are genetically unstable and can rapidly rearrange their genomes. Identification; Viral vectors are often give certain genes that helps identify which cells took up the viral gene e.g antibiotic resistance genes

6. Types of Viral Vectors DNA Viral Vectors; Adenovirus Adeno -Associated virus Herpes virus RNA Viral Virus; Lentivirus Retrovirus

7. Adenovirus It causes common cold. It is the double stranded DNA. It is the naked virus and it has interactions proteins which to penetrate into host cell .

8. Adeno -Associated virus It is a small virus which infects humans. The virus causes a very mild immune response, lending further support to its apparent lack of pathogenicity.

9. Herpes virus This type of viral vector has the ability to deliver large-scale quantities of exogenous DNA. The main role is maintenance of transgene expression.

10. Lentivirus Lentiviruses are a type of retrovirus that are able to integrate into non-dividing cells and do not require mitotic cell division in order to function. Instead, the genome enters the cell DNA via reverse transcription and is incorporated in a random position of the cell genome.

11. Retrovirus Retrovirus vectors are commonly used and known to integrate into the genome of the infected cell in a stable and permanent fashion. Reverse transcriptase in the virus allows integration into the host genome.

12. Applications Gene Therapy: Gene therapy is a technique for correcting defective genes responsible for disease development. There are following delivery system for gene therapy: Physical methods Non-viral vectors Viral vectors

13. In vaccination Viruses expressing pathogen proteins are currently being developed as vaccines against these pathogens, based on the same rationale as DNA vaccines. A viral vaccine induces expression of pathogen proteins within host cells . Since viral vaccines contain only a small fraction of pathogen genes , they are much safer and sporadic infection by the pathogen is impossible . Adenoviruses are being actively developed as vaccines.

14. Thank You