2. Design of immune system

3. Immune system Self/non-self recognition The state of protection from infectious disease 自我非我 Memory Acceptance vs rejection 疫苗 Innate immunityAdaptive immunity

4. Colonize the host Find a nutritionally compatible niche in the host’s body Avoid, subvert, or circumvent the host’s innate and adaptive immune responses Replicate, using host resources Exit and spread to a new host Antigen (Ag) Establishment of infection

5. Innate immunity Physical barrier Biochemical barrier Phagocytes Inflammation

6. Inflammation (cells, soluble mediators) Innate immunity

7. Complement Inflammation Phagocytes Induction of adaptive immunity

8. Phagocytes Innate immunity Recognition of PAMPs by pattern recognition receptors

9. Adaptive immunity Humoral immunity Cell-mediated immunity (CMI) B cells: Antibody T cells

10. Immune recognition Innate (non-specific) immunity Adaptive (specific) immunity Pattern recognition receptors Epitope recognition receptors

11. Innate immunity Adaptive immunity

12. Part I Part III Part II Cells Organs & tissues Functions Antibody response T cell response

13. Cells Organs & tissues Functions Part I

14. WBC Myeloid cells Lymphoid cells Granulocytes Macrophages/ Dendritic cells TB CD4 CD8 NK Immune cells (Natural killer cells) (Tc)(Th) (DC) Adaptive immunity Innate immunity

15. Granulocytes Neutrophils Eosinophils Basophils Mast cells 顆粒性白血球 嗜中性白血球 嗜酸性白血球 嗜鹼性白血球 肥大細胞 (Degranulation)

16. Ag Innate Adaptive ExtracellularPhagocytes B cells Intracellular NK CD8 Tc cells (Altered self) Cytotoxicity CD4 Th Humoral response Cell-mediated immunity (CMI) 1 2 Function of immune cells Ag elimination is based on Ag location DC

17. Adaptive immunity NKPhagocytes Intracellular Extracellular Humoral immunity CMI Th1Th2

18. Infected cells Intracellular Ag Innate immunity Altered self

19. Lymphocytes Ag-specific receptor Adaptive immunity Epitope recognition receptors

20. Lymphoid organs and tissues Primary (Central) Bone marrow Thymus Secondary (Peripheral) Lymph nodes Spleen Peyer’s patches

21. Immune design Adaptive immunity Lymph nodes

22. Lymph node distribution in the body

25. Route Antigen-presenting cells (APC) Inflammation

26. DC T

27. 1. Antigen specificity 2. Diversity 3. Immunological memory 4. Self tolerance Adaptive immunity

28. Design of immune system Ag-specific recognition Pattern recognition

29. Clonal selection ★ Low frequency Immune diversity Adaptive immunity Primary (Central) Secondary (Peripheral) B cell development and humoral immunity Specificity

30. Adaptive immunity Clonal expansion & differentiation

31. Memory response Adaptive immunity

32. Antibody response Part II

33. Antibody structure

34. Antibody structure Effector function Fab Fc Fab: Ag-binding fragment Fc: constant Effector function: complement, FcR

35. Antibody structure Epitope

36. Antibody isotype IgM IgG IgA Fc

37. Five classes of antibody Effector function

38. IgM Natural antibody

39.  C4b C1s 

40. Five classes of antibody Effector function

41. Opsonization: Enhanced phagocytosis by mediators (opsonin) FcR 調理作用

42. Antigen-antibody interaction Immune complex

43. IgA transport

44. IgE

45. Ab is a mediator to activate downstream immune pathways

46. Memory response IgM IgG C’

47. Class switching

48. Neutralizing (Blocking) Binding FcR Complement activation Function of antibody

49. T cell responsePart III CD4 Th B cells CD8 Tc Costimulation (Signal 2) Ag specific recognition (Signal 1) Cytokine (Signal 3) Humoral immunity CMI

50. T cell Receptor (TCR) Ag specific recognition (Signal 1)

51. Antigen-presenting cells (APC) T cell recognition & activation

52. APC T-DC interaction MHC: antigen presentation Ag specific recognition (Signal 1)

53. T cell recognition: MHC restriction CD8CD4

54. Co-receptor: CD4 & CD8

55. MHC HLA: Human leukocyte antigen Epitope

56. MHC 內 APC

57. Ag processing & presentation to CD4 T 外

58. Ag processing & presentation to CD8 T 內

60. T cell activation & expansion Costimulation (Signal 2) Clonal expansion

61. Th cell differentiation IL12 IL4

62. 內 Cytokine (Signal 3) in T cell differentiation 1 Cytokine: Effector function Interferon 

65. CD4 Th B cells CD8 Tc Costimulation (Signal 2) Ag specific recognition (Signal 1) Cytokine (Signal 3) Humoral immunity CMI 1 2

67. APC 2 Costimulation

68. Innate immunity Adaptive Immunity (Humoral, CMI)

69. Adaptive immunity Clonal expansion & differentiation

70. 1. Antigen specificity 2. Diversity 3. Immunological memory 4. Self tolerance Adaptive immunity

71. Tolerance

72. Host-pathogen relationship Persistent infection Immune evasion Persistence