1. Immunity to Infectious Diseases
Immunity to Infectious Diseases

2. Outline Routes and sites of infection
Routes and sites of infection
Mechanisms of tissue injury in infection
Timing of immune responses to infection
Regulation of cell-mediated (TH1) vs. humoral immunity (TH2) in infections
Effector mechanisms for immunity to different pathogens
Immunizations/vaccines

3. Routes and sites of infection
Routes and sites of infection

4. Primary Route of Infection: Microbial Adherence and Invasion of epithelial tissues (lung, gut, other)
Janeway, 2001

5. Primary Route of Infection: Microbial Adherence and Invasion of epithelial tissues (continued).
Janeway, 2001

6. Infection compartments
Infection compartments
Janeway, 2001

7. Mechanisms of tissue injury in infection
Mechanisms of tissue injury in infection

8. Mechanisms of Pathogen-induced tissue Damage

9. Mechanisms of Pathogen-induced tissue Damage

10. Timing of immune responses to infection
Timing of immune responses to infection

11. Time course of immune response to acute infection.
Time course of immune response to acute infection.
Janeway, 2001

12. Regulation of cell-mediated (TH1) vs. humoral immunity (TH2) in infections

13. Infection induced Th1 vs. Th2 responses.

14. Effector mechanisms for immunity to different pathogens
Effector mechanisms for immunity to different pathogens

15. Innate recognition of microbes and phagocytosis by macrophages
Innate recognition of microbes and phagocytosis by macrophages

16. Microbial activation of complement pathways for inflammation.
Microbial activation of complement pathways for inflammation.

17. Protective effector mechanisms of antibody.
Protective effector mechanisms of antibody.

18. Protective effector mechanisms of antibody.
Protective effector mechanisms of antibody.

19. Effector T cell populations and effector mechanisms.

20. Immunizations/vaccines
Immunizations/vaccines

23. Summary
Immunity to infection depends on a combination of innate mechanisms (phagocytosis, complement, etc.) and antigen specific adaptive responses (antibody, effector T lymphocytes).
The immune system regulates which specific responses predominate (humoral vs. cell-mediated) based on the body compartment infected (intracellular vs. extracellular) and on cytokine signals present at initial antigen contact (Th1 vs. Th2 responses).

24. Summary-continued
Disease-causing microbes have virulence mechanisms that resist or evade innate and/or specific immune effector functions.
Recovery from natural infection or artificial immunization promote specific longterm immunity to re-infection (immunological memory).

25. Thank you