1. Gene therapy and Viral Vectors Lecture 6

2. Contents Introduction to gene therapy Delivery of Therapeutic Genes Gene Therapy Targets Delivery Modes Steps in Gene Therapy Gene Therapy Non Viral vectors Liposomes Polycation conjugates Cell bases therapies Cancer gene therapy Gene therapy in plants Ethical issues in gene therapy Therapeutic Gene Regulation Control of therapeutic gene expression Prospects for gene therapy Gene therapy: A treatment of Altered Genes Methods of Gene therapy Clinical applications of gene therapy Gene therapy approaches to enhance antitumor immunity Ethical and social problems of gene therapy

3. Aims of Gene therapy An ideal gene delivery vector should be effective, specific, long lasting and safe. Therefore, there is a need for a delivery system,: which must first overcome the extracellular barriers (such as avoiding particle clearance mechanisms, targeting specific cells or tissues and protecting the nucleic acid from degradation) and, subsequently, the cellular barriers (cellular uptake, endosomal escape, nuclear entry and nucleic release)

4. Non viral vectors Non-viral vectors are safer, of low cost, more reproducible and do not present DNA size limit. The main limitation of non-viral systems is their low transfection efficiency, although it has been improved by different strategies and the efforts are still ongoing. However, viral vector has dominated the clinical trials in gene therapy for its relatively high delivery efficiency.

7. Non Viral Delivery Systems Inorganic particles (nanoparticles) ◦ Calcium phosphate ◦ Silica ◦ Gold ◦ Magnetic Synthetic or natural biodegradable particles Physical methods

8. Nanotechnology/Nanoscience Nanotechnology is science, engineering, and technology conducted at the nanoscale, which is about 1 to 100 nanometers. Nanoscience and nanotechnology are the study and application of extremely small things and can be used across all the other science fields, such as chemistry, biology, physics, materials science, and engineering.

9. Nanoscale

10. History The ideas and concepts behind nanoscience and nanotechnology started with a talk entitled “There’s Plenty of Room at the Bottom” by physicist Richard Feynman at an American Physical Society meeting at the California Institute of Technology (CalTech) on December 29, 1959, long before the term nanotechnology was used. In his talk, Feynman described a process in which scientists would be able to manipulate and control individual atoms and molecules. Over a decade later, in his explorations of ultraprecision machining, Professor Norio Taniguchi coined the term nanotechnology. It wasn't until 1981, with the development of the scanning tunneling microscope that could "see" individual atoms, that modern nanotechnology began.

11. Product based nanotechnology

12. Synthesis of Inorganic nanoparticles

13. Bottom up approach Substrate+Reducing agent Color change confirms that reaction has taken place UV/Vis spectroscopy confirms particle synthesis The colloidal solution is centrifuged to get the pallet of elemental form of metal at the bottom

14. Characterization of nanoparticles X-ray fluorescence (XRF) confirms elemental composition Fourier transfer infrared spectroscopy (FTIR) confirms presence of different functional groups X-ray power diffraction (XRD) confirms structure Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirms morphology (size, shape)

15. Review paper http://www.nanoscalereslett.com/content/ pdf/1556-276X-9-252.pdf