1. Structure of Lymphoid System Components

2. FUNCTIONS OF THE IMMUNE SYSTEM PROTECTION AGAINST FOREIGN INVADERS INTO BODY PRODUCE / PROTECT GERM FREE ENVIRONMENT OF THE BODY

3. EXAMPLES OF IMMUNE RESPONSE REACTION AGAINST MICROORGANISMS: BACTERIA, VIRUSES, PARASITES REACTION AGAINST TUMOR CELLS ALLERGIC REACTIONS: HAY FEVER, POISON IVY AUTOIMMUNE REACTION: ARTHRITIS, TYPE I DIABETES GRAFT REJECTION http://www.greenlifestyle.be 32412 Appendix

4. Main Player, The Lymphocyte In different settings

5. Objective – Overview of Lymphoid System and Lymphopoiesis Primary organs Secondary organs

6. Life Cycle of Lymphocytes Fetal organs Bone marrow Primary lymphoid organs (Antigen independent development) - Thymus – T lymphocytes - Bone marrow - B lymphocytes Secondary lymphoid organs (Antigen dependent development) –Lymph nodes –Lymphoid nodules –Spleen

7. Life Cycle of Lymphocytes Fetal organs Bone marrow

8. Life Cycle of Lymphocytes Bone marrow

9. Life Cycle of Lymphocytes Bone marrow - megakaryocyte

10. Life Cycle of Lymphocytes Bone marrow Seeding primary organs

11. Thymus Growth pattern – regress after childhood Reticulum framework – epithelium (from endoderm) Cortex - absence of exogenous antigens Epithelial microenvironment Lymphopoiesis Blood-thymus barrier Medulla

12. Thymus Growth pattern - regress after childhood

13. Thymus Reticulum framework - epithelium Epithelium

14. Thymus Cortex: absence of exogenous antigens Epithelial microenvironment Lymphopoiesis Blood-thymus barrier (cortical barrier only) Medulla

15. Thymus Cortex and medulla

17. Thymus Cortex Epithelium

18. Thymus Cortex

19. Thymus Cortex cell division and cell death

20. Thymus Cortex and medulla

21. Thymus Medulla Hassall’s corpuscles

22. Lymph Nodes - Filtration of Lymph Basic structure Lymphatic vessels Vasculature Reticular framework (mesoderm) Cortex o Follicles - B lymphocytes o Perifollicular - T lymphocytes Medulla o Cords o Sinuses

23. Lymph Node Hilum = single site for blood entry and exit

27. Lymph Nodes - Filtration of Lymph Basic structure Lymphatic vessels Vasculature

28. Lymph Nodes - Filtration of Lymph Basic structure - reticular framework

29. Lymph Nodes - Filtration of Lymph Basic structure - reticular framework

30. Lymph Nodes - Filtration of Lymph Basic structure - reticular framework

31. Lymph Nodes - Filtration of Lymph Cortex o Follicles - B lymphocytes (in lymph nodule) o Perifollicular - T lymphocytes (in paracortex) B lymphocytes T lymphocytes

32. Medulla – cords and sinusesCortex Lymph Nodes - Filtration of Lymph

33. Lymph Nodes - Filtration Of Lymph Medulla – cords and sinuses

36. Lymph Nodes and Lymphoid Tissue Lymph flow Lymphopoiesis Lymphocyte circulation –High endothelial venules Receptors for T&B cells only –One-way traffic Gut-associated lymphoid tissue –Tonsils –Peyer’s patches

37. Lymph Nodes and Lymphoid Tissue Lymph flow

39. Lymph Nodes and Lymphoid Tissue Lymphopoiesis

40. Lymph Nodes and Lymphoid Tissue Lymphopoiesis

41. Lymph Nodes and Lymphoid Tissue Lymphocyte circulation –High endothelial venules Receptors for T&B cells only –One-way traffic

42. Lymph Nodes and Lymphoid Tissue Lymphocyte circulation High endothelial venules Receptors for T&B cells only One-way traffic

43. Recycling of Lymphocytes Through Lymph Nodes

44. Lymph Nodes – filtration of lymph to allow potentially active lymphocytes to see/respond to its antigen if present in the lymph

45. Lymph Node - Summary

46. Lymphoid Tissue Gut-associated lymphoid tissue –Tonsils

47. Lymphoid Tissue Gut-associated lymphoid tissue –Peyer’s Patches

48. 204 Peyer’s Patches in the human appendix

49. Peyer’s Patches

50. Activated Lymphocyte that has seen its antigen

52. Roles and Specific Actions of Antibodies in Immunity Complement - mediated lysis Opsonization - promote phagocytosis Toxin neutralization Prevention of microbial binding to mucosal surface Virus neutralization - interferes with cell penetration Degranulation of mast cells http://www.youtube.com/watch?v=Ys_V6FcYD5I&feature=related

53. Spleen Overall structure Vascular arrangement White pulp Central artery Periarteriolar lymphatic sheath Follicles - B lymphocytes Red pulp Venous sinuses Pulp cords (Billroth’s strands/Cords of Billroth) Marginal zone http://www.youtube.com/watch?v=0CqWulccLMo

54. Spleen Overall structure Vascular arrangement

55. Spleen Overall structure Vascular arrangement

56. Spleen White pulp Central artery Periarteriolar lymphatic sheath Follicles - B lymphocytes Red pulp Venous sinuses Pulp cords (Billroth’s strands/Cords of Billroth) Marginal zone

57. Spleen White Pulp Red Pulp

58. Spleen White pulp

59. Spleen Reticular fiber framework Reticulum cell - mesoderm Blood flow Penicillar arteries Extravascular sojourn of blood cells Filtration Removal of old red blood cells Pitting of reticulocytes

60. Spleen Reticular fiber framework –Reticulum cell - mesoderm

61. Spleen Reticular fiber framework

62. Spleen Blood flow –Penicillar arteries Macrophages

65. Spleen Marginal zone Billroth’s Strand Littoral cells: picket- fence type endothelial cells of vascular sinus

67. Spleen Blood flow –Extravascular sojourn of blood cells

68. Spleen Blood flow –Extravascular sojourn of blood cells

69. Spleen Blood flow Filtration Removal of old red blood cells Littoral cells: picket- fence type endothelial cells of vascular sinus

70. Spleen Blood flow Filtration Removal of old red blood cells

71. Spleen Blood flow Filtration Removal of old red blood cells

73. Spleen Blood flow Filtration Removal of old red blood cells

74. Activated!

75. Natural Killer Cells Http://www.Youtube.Com/watch?V=hnp1e aylhos&feature=fvwp&nr=1Http://www.Youtube.Com/watch?V=hnp1e aylhos&feature=fvwp&nr=1

76. Summary

77. Functions of the Immune System Protection against foreign invaders into body Produce/protect germ free environment

78. Three Key Steps of Combating Infections reak the cycle of transmission ill the infectious agent ncrease host resistance e.g., increase immunity of host

79. Lines of Defense Second line: Phagocytes at work Neutrophils to ill the infectious agent Monocytes - macrophage

80. Characteristics of Immunity Acquired - requires exposure to antigens Specificity - response is unique to exposure Memory - remembers previous exposure ncrease host resistance through Immunity

81. Characteristics of Immunity Acquired - M ust be developed Specificity - Antibodies made are specific to specific molecules on the antigen of exposure

82. Characteristics of Immunity Memory: quick second response –Long lived cells

83. Types of Immune Response Antibody: mediated –Glycoproteins recognize and bind to antigens Cell: mediated –Specifically active cells recognize cell - bind antigens

84. Endocrine System Next time

86. Mammals

87. Flat Stanley

100. Http://www.Youtube.Com/watch?V=4238n n8hmgqHttp://www.Youtube.Com/watch?V=4238n n8hmgq Neil Degrasse Tyson - Stupid Design http://www.youtube.com/watch?v=9Eo5Md HMNcw http://www.youtube.com/watch?v=6oxTMUTOz0w&feature=related