AIDS: Evolution of an Epidemic

Lecture 2 – AIDS and the HIV Life Cycle

by Bruce D. Walker, MD

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1. Start of Lecture 2
2. Welcome by HHMI Vice President Dr. Peter Bruns
3. Profile of Dr. Bruce Walker
4. Introductory remarks by Dr. Walker
5. How viruses cause disease
6. Persistent viral infections have an acute initial infection phase
7. Video: Symptoms of acute HIV infection
8. Symptoms of HIV acute viral infection
9. Why HIV tests show no infection during acute phase
10. Development of an antibody response
11. Measuring HIV RNA detects high HIV levels during acute infection
12. HIV RNA can be detected before antibodies to HIV
13. Does HIV infection progress the same way in all people?
14. HIV viral load as a predictor of disease progression
15. Viral load compared to helper T cell level
16. Animation: HIV life cycle (part 1)
17. Helper T cells orchestrate the immune response
18. Animation: HIV life cycle (part 2)
19. Summary
20. Q&A: What can be done after accidental HIV exposure?
21. Q&A: What conditions can HIV survive in?
22. Q&A: If the virus integrates, how does T cell count decline?
23. Is the immune system trying to keep HIV in check?
24. Humoral immunity and antigen binding
25. Antibodies neutralize HIV by binding to its surface proteins
26. Can neutralizing antibodies prevent initial infection?
27. Mechanism of cytotoxic T lymphocytes (CTLs)
28. Animation: Antigen presentation and CTL
29. Video: CTL killing a target cell
30. Do CTLs help limit HIV infection?
31. How helper T cells orchestrate an immune response
32. By eliminating helper T cells, HIV disables the immune response
33. Summary
34. Q&A: What causes a person to have a high or low viral load?
35. Q&A: Do mutations cause changes in the HIV envelope proteins?
36. Q&A: Do some people not have the receptors that HIV uses?
37. Q&A: Why can't we use antibodies to HIV as a vaccine?
38. Q&A: Could you make drugs to attack HIV's protease or integrase?
39. Closing remarks by HHMI Vice President Dr. Peter Bruns

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