1. Tolerance and Autoimmunity Autoimmunity– inappropriate response of the immune system against self component. Tolerance – mechanisms that exist to protect an individual from potentially self-reactive lymphocytes.

2. Tolerance and Autoimmunity

3. Tolerance and Autoimmunity

4. Tolerance and Autoimmunity Establishment and Maintenance of Tolerance Factors that promote tolerance:  High doses of antigen  Persistence of antigen in host  Intravenous or oral introduction  Absence of adjuvants  Low levels of costimulators

5. Tolerance and Autoimmunity Establishment and Maintenance of Tolerance

6. Tolerance and Autoimmunity Regulatory T cells (Treg cells)

7. Tolerance and Autoimmunity

8. Tolerance and Autoimmunity

9. Tolerance and Autoimmunity Contributors to autoimmunity:  CD4+ T cell  MHC  TCR

10. Tolerance and Autoimmunity Proposed mechanisms for induction of autoimmunity

11. Autoimmunity Molecular mimicry

12. Autoimmunity Current Treatments:  Immunosuppressive drugs  Thymectomy  Plamapheresis  TNF-a blockers