1. Future directions in HIV basic science research The hunt for a cure

2. Future Directions A new vaccine approach. Targeting and purging the latent reservoirs. Targeting and removing integrated virus. Stem cell based therapies. Targeting and controlling immune activation.

3. A “new” vaccine approach- Use another virus to “trick” the immune response to SIV Rhesus Cytomegalovirus is a monkey herpesvirus. They replaced genes in Rhesus Cytomegalovirus with those of SIV.

4. Annual Reviews

5. Less restricted. Rhesus Cytomegalovirus that expresses SIV genes (strain 68-1 RhCMV) expands the CD8+ T cell response to SIV. N Goonetilleke, and A J McMichael Science 2013;340:937- 938 Published by AAAS

6. A new vaccine approach They found that vaccination with Rhesus Cytomegalovirus containing SIV allowed protection from SIV challenge in monkeys (Rhesus Macaques) The immune responses in these animals were not the same as the responses in animals exposed to SIV without the vaccine = better protection

7. Targeting and purging the latent reservoirs HIV latency and persistence is the biggest hurdle in a cure. Targeting and removing the latent reservoir from the body remains an important therapeutic target.

8. Short-lived infected cell Long-lived infected cell (latently infected) HIV persistence during therapy

9. Short-lived infected cell Long-lived infected cell (latently infected) HIV persistence during therapy Antiretroviral therapy

10. Short-lived infected cell Long-lived infected cell (latently infected) HIV persistence during therapy

11. Antiretroviral therapy Latently infected CD4+ T lymphocytes are rare in vivo: Approximately 1 per 10 6 total resting CD4 + T cells Probably constitute around 10 5 -10 6 cells per patient

12. Formation of HIV latency

13. Pseudomonas Exotoxin gp120 Infected Cell Anti-HIV Immunotoxin 3B3:N31H/Q100eY(dsFv)-PE McHugh et al.; 2002 Anti-gp120

14. Prostratin or Bryostatin or ?

16. Marsden and Zack (2010) Future Virol. 5(1): 97–109. Activation/elimination strategy for clearing latently-infected cells:

17. Targeting Integrated Virus

19. HIV Lifecycle

20. Structures of cleavage enzymes. Schiffer J T et al. J. Virol. 2012;86:8920-8936

21. Targeted gene knockout by DNA-editing enzymes. Schiffer J T et al. J. Virol. 2012;86:8920-8936

22. Integrated Virus Targeting Highly specific, efficient way of getting integrated virus out of cell. Problems with delivery to the cell. Highly promising

23. Stem Cell Based Therapies Most include gene therapy to modify the hosts genetic makeup to: – Make cells that are resistant to HIV infection And/or – Make cells that can target and kill HIV infected cells.

24. http://www.nytimes.com/2011/11/29/health/new-hope-of-a-cure-for-hiv.html?pagewanted=all

25. Stem cell based Anti-HIV Gene Therapy Kitchen SG et al. Stem cell-based anti-HIV gene therapy. Virology. 2011 Containing at least 1 anti-HIV gene

26. Multiple anti-HIV gene therapy approach Selected anti-HIV genes 1.Potent HIV inhibitors at early stage of viral life cycle 2.Distinct anti-HIV mechanisms Goals 1.Inhibit multiple HIVs CCR5 tropic HIVs CXCR4 tropic HIVs Multi-drug resistant HIVs 2.Prevent emergence of resistant HIV mutants CCR5-siRNA Hu-TRIMcyp C46 entry inhibitor HIV TCR

27. “Engineered Immunity” Stem cell based approaches Would allow direct genetic modification of progenitor (“baby”) cells in the body Would allow prolonged self-renewal of modified cells that would have long life in the body Cells would undergo normal development and be recognized as part of the body

28. Goal: We are interested in using molecularly cloned, HIV- specific T cell receptors (TCRs) from HIV-specific CD8+ T cells and other HIV-targeting molecules to modify human blood forming stem cells to target and kill HIV in infected individuals Engineering Antiviral Immunity

29. Virus Infected cells T cell TCR  TCR  Stem cell Viral Vectors Containing Cloned TCRs T cell “Genetic Vaccination” to HIV TCR  TCR  TCR  TCR  TCR  TCR 

30. CD34+ 1. Sort CD34+ 6. Analyze TCR Expression/F unction 6-12 weeks Fetal Liver 2. Transduce with Anti-HIV TCR or Control TCR HLA-A*0201+ Tissue 3.Combine with fetal thymus tissue and liver stroma, implant under kidney capsule 2a. Viably freeze fraction CD34+ 4. Thaw and Transduce with Anti-HIV TCR Or Control TCR 3 weeks 5. Tail Vein Inject Humanized Mouse Model of HIV Infection: The NSG-CTL Model Infect with HIV-1 NL4-3HSA-HA NSG Irradiate

31. HIV-Specific TCR suppresses of HIV in humanized mice Kitchen et al., PLoS Pathogens 2012

32. GMP Level Closed System Gene Transduction and Cell Processing Isolex Apheresis Cytomate Culture Gene Transfer Product Final Infusion Product Isolex

33. Targeting Immune Activation and HIV HIV activates the immune response during infection HIV replicates in an active immune response We can target the virus (ARV), we need to also target the immune response to make it better able to clear HIV One way is to target specific molecules to lower levels of immune activation to decrease HIV levels.

34. HIV infection in the gut (Intestines, Colon) causes problems with the immune response

35. Immune activation and inflammation in HIV‐1 infection: causes and consequences The Journal of Pathology Volume 214, Issue 2, pages 231-241, 27 DEC 2007 DOI: 10.1002/path.2276 http://onlinelibrary.wiley.com/doi/10.1002/path.2276/full#fig1 Volume 214, Issue 2, http://onlinelibrary.wiley.com/doi/10.1002/path.2276/full#fig1 There is a lot going on in HIV infection. Like antiretroviral therapy and the HIV lifecycle, if we can target multiple events we may be able to allow the immune response to clear HIV.