Presentation on DNA Vaccines Essay -- Powerpoint Presentation

Vaccines †¢ Vaccines are â€Å"one of the greatest achievements of modern medicine† †¢ In developed nations, vaccines have almost exterminated polio and smallpox and tightly controlled diseases like hepatitis A and B or typhus †¢ There are three generations of vaccinations †¢ First generation vaccines are either weakened or killed forms of whole organisms †¢ There is a problem with first-gen vaccines: the pathogens can still revert to dangerous forms and cause diseases in immunocompromised vaccine recipients. †¢ Second generation vaccines are specific protein antigens, which are safer, but cannot generate killer T cell responses DNA Vaccines †¢ Third generation of vaccines †¢ Consist of recombinant plasmids that have been transformed to produce one to two proteins form a pathogen †¢ This DNA is injected directly into somatic cells, where, through transcription and translation, the proteins are created. †¢ The proteins are recognized as foreign and processed by the cell and displayed on the cell surface by MHC markers †¢ Here, they raise helper T cell, cytotoxic T cell, and antibody immune responses. Current applications †¢ DNA vaccines have had limited success in clinical trials †¢ A veterinary DNA vaccines for use on horses to protect from West Nile virus has been approved †¢ In June 2006 and August 2007, positive results were announced for vaccines against bird flu and multiple sclerosis, respectively. †¢ The technique still needs to proven conclusively in human testing Use of Plasmid Vectors †¢ Highly active expression vectors elicit the best immune response †¢ Strong viral promoters, such as Rous Sarcoma virus (RSV) or cytomegalovirus (CMV) promoters are most commonly used †¢ The plasmids most commonly used als... ... Cited Continued †¢ Baker, Barbara, et. al. â€Å"The N gene of tobacco confers resistance to tobacco mosaic virus in transgenic tomato.†Proceedings of the National Academy of Sciences of the United States93 (1996) 8776–8781. †¢ Feldstein, Paul. Personal interview. July 2008. Fig. 8 Images †¢ Fig. 1: http://www-tc.pbs.org/wgbh/nova/bioterror/images/germ_dna.jpg †¢ Fig 2: http://www.gen.cam.ac.uk/Images/summers/plasmids.jpg †¢ Fig 3:http://www.bio.davidson.edu/people/kabernd/seminar/2002/method/gtwmeth/genegungtw.gif †¢ Fig 6:http://upload.wikimedia.org/wikipedia/commons/d/da/Making_of_a_DNA_vaccine.jpg †¢ Fig. 4: http://en.wikipedia.org/wiki/Image:Antibody.svg †¢ Fig. 5: http://en.wikipedia.org/wiki/Image:Antigen_presentation.jpg †¢ Fig. 7: http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/em_tmv.gif †¢ Fig 8: http://www.technologyreview.com/files/8829/DNAVaccineBG.jpg