Sri Ram .P Date: 11/25/03 Course: Scientific Discovery Instructor: Dr. A. Vankley

1. Sri Ram .PDate: 11/25/03Course: Scientific Discovery Instructor: Dr. A. Vankley

2. Cell Mediated Immunity “Discoveries concerning the specificities of Cell Mediated Immune defenses and their implications ”

3. Immunity?

4. Foreign Invaders

5. Self Markers

6. Markers of Non-Self

7. Organs and tissues of the immune system

8. Lymphatic vessels form a circulatory system that operates in close partnership with blood circulation.

9. Lymph Node

10. Cells of the Immune System

11. B cells become plasma cells, which produce antibodies when a foreign antigen triggers the immune response.

12. Antibody

13. Antibodies produced by cells of the immune system recognize foreign antigens and mark them for destruction.

14. Activation of B cells to make antibody

15. T lymphocytes become CD4+ or helper T cells, or they can become CD8+ cells, which in turn can become killer T cells, also called cytotoxic T cells.

16. Activation of helper T cells

17. Activation of cytotoxic T cells

18. Cytokines Complement

19. Natural Killer cells , Phagocytes and Granulocytes asa

20. Immunity and Cancer

21. Human Tissue Typing for Organ Transplants

22. Rolf M. Zinkernagel

23. Rolf M. Zinkernagel • Born: January 6, 1944, Basel, Switzerland • Primary and Secondary Education in and around Basel. • 1962-68:University of Basel, Faculty of Medicine • 1969- Began his life as Surgeon in Basel but soon realized this was not his field. • 1969-70:Postdoctoral Fellow, Laboratory for Electron Microscopy, Institute of Anatomy, University of Basel

24. Rolf M. Zinkernagel • 1971-1973 Postdoctoral Fellow, Institute of Biochemistry, University of Lausanne, Switzerland • He learnt his immunology here. • He also familiarized himself with the 51-Cr. Release assay to study the immune mechanism destruction of host cells. • His work with infectious agents and immunity studies motivated him for further study .

25. Rolf M. Zinkernagel • 1973-75:Visiting Fellow, Department of Microbiology, The John Curtin School of Medical Research, Australian National University, Canberra, Australia • 1976-79:Associate (Assistant Professor), Department of Immunopathology, Research Institute of Scripps Clinic, La Jolla, California

26. Rolf M. Zinkernagel • 1979-88:Associate Professor, Department of Pathology, University of Zurich, University Hospital, Zurich • 1988-92-Full professor in same place • 1992-Head, Institute of Experimental Immunology, Zurich

27. Peter C. Doherty

28. Peter C. Doherty • Born: October 15, 1940, Australia • 1962:BVSc University of Queensland, Australia • 1966:MVSc University of Queensland, Australia • 1967-71:Scientific Officer, Senior Scientific Officer, Department of Experimental Pathology,Moredun Research Institute, Edinburgh, Scotland

29. Peter C. Doherty • 1972-75:Research Fellow, Department of Microbiology, The John Curtin Schoolof Medical Research, Australian National University, Canberra, Australia • 1975-82: Associate Professor/Professor, The Wistar Institute, Philadelphia, PA • 1982-88:Professor and Head, Department of Experimental Pathology, The John CurtinSchool of Medical Research, Australian National University, Canberra

30. Peter C. Doherty • 1988:Chairman, Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN • 1992:Adjunct Professor, Departments of Pathology and Pediatrics, University of Tennessee, College of Medicine, Memphis, TN  

31. Paired Up • Peter Doherty first studied the pathogenesis of Semliki Forest virus infection in the mouse, then switched to the lymphocytic choriomeningitis virus (LCMV) model which was a much more powerful tool for immunological analysis.

32. Paired Up • Zinkernagel wanted to work with R. Blanden on cell-mediated immunity against Salmonella and Listeria to learn more about the role of cell-mediated versus antibody-dependent immune effector mechanisms in these infectious disease models . But lack of space in the lab paired both of them.

33. Background In 1960-70s immunology was attempted to be understood in terms of infectious diseases. It was then Largely pre-occupied with antibody and T-cell responses against foreign protein antigens or chemically defined small molecules called haptens.

34. Background • Mechanism of foreign-organ graft rejection was intensively studied, although the biological function of MHC was largely unclear. • Only few people studied immunity against infectious agents.

35. Background • Antibacterial and antiviral T-cell mediated immunity and the capacity of immunized cytotoxic CD8+ T cells to destroy either virus infected or allogeneic target cells in vitro- was the work in progress at JCSMR.

36. Techniques and Study • Doherty and Zinkernagel jointly begin work on CMI in LCMV (Lymphocytic choriomeningitis virus). • 51 cr. Release assays as cytotoxicity assay was used by Zinkernagel. • Doherty was efficient in cannulation and could draw few ml of CSF from cisterna magna of the mice.

37. Techniques and Study • Whether inflammatory cells in the CSF of mice infected intra cerebrally with LCMV were cytolytic in vitro and whether there was any correlation between cytotoxic T- cell activity and severity of choriomeningitis .

38. Observations • Cytotoxic T cells specifically destroying LCMV infected target cells could be found in CSF of normal mice but not in nude mice lacking thymus and T-cells. • T-cells probably also destroyed infected meningeal and ependymal cells in vivo and this was the pathogenic mechanism causing choriomeningitis.

42. Observations • The findings were published in the Journal of Experimental Medicine in March 1973. • Same journal had a paper showing mice with different major histocompatibility gene complexes differed in susceptibility to LCMV after cerebral infection. • This prompted to experiment further on this.

43. Experiment • 6-8 mice of inbred and cross-bred strains were infected intra cerebrally with LCMV. • 2 of each were sacrificed on day 7 after infection when first mouse became sick. –to test antiviral cytotoxic T –cell activities in spleens. • Remaining mice were monitored for lethal disease during next 10days .

44. Experiment • All mice died in course of time. • But only some generated virus-specific cytotoxic activity that was measurable in vitro. • Result- Either cytotoxic T-cells have nothing to do with choriomeningitis or the test was inadequate.

46. Reassessment • Mouse L-929 cells (fibroblast cell lines) were used as target cells to assess cytotoxic T-cell activity. • Fortunately the mouse CBA strain and the L-cells derived from mouse strain C3H were closely related. • Both possessed the same MHC-molecules (H-2k).

47. Reassessment • Studying further, LCMV -immune spleen cells from all mice that possessed H-2k haplotype (as do CBA mice) including the cross breeds with H-2k lysed L-929 cells infected with virus. • But did not lyse uninfected targets or those infected with third-party virus. • All spleen cells derived from immunized mice that were not of H-2k type failed to do so.

48. Further Studies • Two additional experiments showed that LCMV immune lymphocytes from non-H2k strains of mice were able to lyse LCMV infected target cells of same MHC –type. • LCMV did not infect these cell lines. • Used macrophages from the peritoneum of the mice as target cells. Adhered to plastic, readily infectable and labeled with Cr 51.

49. Further Studies • Criss-cross experiments showed that LCMV immune T-cells from H-2b mice lyse LCMV-infected macrophages of H-2b origin but not those of other H-2 types and vice versa. • These findings were reported in December to Nature and were published in April,1974

50. Similar Finding • TNP-specific cytotoxic T cells lysed syngeneic TNP-lated targets more efficiently than allogeneic TNP-lated targets. • European journal of immunology –same time . But independent.