1. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture prepared by Kathleen A. Ireland, Seabury Hall, Maui, Hawaii Anatomy & Physiology M A R T I N I FIRST EDITION C h a p t e r 22 The Lymphoid System and Immunity PowerPoint® Lecture Slides prepared by Jason LaPres Lone Star College - North Harris Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

2. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings The lymphatic system Contains cells, tissues, and organs responsible for defending the body Lymphocytes resist infection and disease by responding to Invading pathogens such as bacteria or viruses Abnormal body cells such as cancer cells Foreign proteins such as toxins Lymphatic system

3. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.1 Figure 20.1 The Components of the Lymphatic System

4. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lymph Lymphatic vessels Lymphoid tissues and organs Lymphocytes and supporting phagocytic cells The lymphatic system consists of

5. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Primary function is production, maintenance, and distribution of lymphocytes Lymphocytes must: Detect where problems exist Be able to reach the site of injury or infection Functions of lymphatic system

6. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lymphatic capillaries Small lymphatic vessels Major lymph-collecting vessels Lymphatic vessels include

7. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.2 Lymphatic Capillaries Figure 20.2a, b

8. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.3 Lymphatic Vessels and Valves Figure 20.3a, b

9. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Superficial and deep lymphatics Thoracic duct Cisterna chyli Right lymphatic duct Major lymph-collecting vessels

10. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.4a Figure 20.4 The Relationship between the Lymphatic Ducts and the Venous System

11. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.4b Figure 20.4 The Relationship between the Lymphatic Ducts and the Venous System

12. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.4c Figure 20.4 The Relationship between the Lymphatic Ducts and the Venous System

13. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Three classes of lymphocytes T (thymus dependent) cells B (bone marrow-derived) cells NK (natural killer) cells Lymphocytes

14. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Involves bone marrow, thymus, and peripheral lymphoid tissue B cells and NK cells mature in bone marrow T cells mature in the thymus Lymphocyte production (lymphopoiesis)

15. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.5a-c Figure 20.5 The Derivation and Distribution of Lymphocytes

16. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Connective tissue dominated by lymphocytes Lymphoid nodules Lymphocytes densely packed in areolar tissue Found in the respiratory, digestive, and urinary tracts MALT (mucosa-associated lymphoid tissue) Collection of lymphoid tissues linked with the digestive system Lymphoid tissue

17. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.6 Lymphoid Nodules Figure 20.6

18. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lymph nodes – function in the purification of lymph Afferent lymphatics – carry lymph to nodes Efferent lymphatics – carry lymph from nodes Deep cortex dominated by T cells Outer cortex and medulla contains B cells Lymphoid organs

19. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.7 The Structure of a Lymph Node Figure 20.7

20. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Located behind sternum in anterior mediastinum Capsule Two lobes Divided into lobules, each with a cortex and medulla Cortical lymphocytes surrounded by reticular endothelial cells Maintain blood–thymus barrier Secretes thymic hormones: thymosins, thymopoietins, and thymulin The Thymus

21. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.8 The Thymus Figure 20.8a-c

22. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Largest mass of lymphoid tissue Cellular components form pulp Red pulp contains RBC White pulp similar to lymphoid nodules Spleen functions include Removal of abnormal blood cells and other blood components Storage of iron Initiation of the specific immune response The Spleen

23. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.9 The Spleen Figure 20.9a-c

24. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nonspecific defenses Do not distinguish one type of threat from another 7 types Specific defenses Protect against particular threats Depend upon the activation of lymphocytes Lymphatic system and body defenses

25. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Keep hazardous organisms outside the body Includes hair, epithelia, secretions of integumentary and digestive systems Nonspecific Defenses: Physical barriers

26. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Figure 20.10 Nonspecific Defenses (Part 1 - Physical Barriers)

27. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Remove cellular debris and respond to invasion by foreign pathogens Monocyte-macrophage system - Fixed and free Microphages – Neutrophils and eosinophils Move by diapedesis Exhibit chemotaxis Nonspecific Defenses: Phagocytes

28. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Nonspecific Defenses (Part 2 - Phagocytes) Figure 20.10

29. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Constant monitoring of normal tissue by NK cells NK cells Recognize cell surface markers on foreign cells Destroy cells with foreign antigens Nonspecific Defenses: Immunological surveillance

30. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings NK cell activation Recognition of unusual surface proteins Rotation of the Golgi toward the target cell and production of perforins Release of perforins by exocytosis Interaction of perforins causing cell lysis

31. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Figure 20.10 Nonspecific Defenses (Part 3 - Immunological Surveillance)

32. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.11 Figure 20.11 How Natural Killer Cells Kill Cellular Targets

33. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nonspecific Defenses: Interferons (cytokines) Small proteins released by virally infected cells Trigger the production of antiviral proteins Three major types of interferons are: Alpha – produced by leukocytes and attract/stimulate NK cells Beta – secreted by fibroblasts causing slow inflammation Gamma – secreted by T cells and NK cells stimulate macrophage activity

34. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Nonspecific Defenses (Part 4 - Interferons) Figure 20.10

35. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nonspecific Defenses: Complement system Cascade of ~11 plasma complement proteins (C) Destroy target cell membranes Stimulate inflammation Attract phagocytes Enhance phagocytosis

36. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Complement proteins interact with on another via two pathways Classical Alternative

37. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Figure 20.10 Nonspecific Defenses (Part 5 - Complement System)

38. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.12 Complement Activation Figure 20.12

39. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nonspecific Defenses: Inflammation Localized tissue response to injury producing Swelling Redness Heat Pain Effects of inflammation include Temporary repair of injury Slowing the spread of pathogens Mobilization of local, regional, and systemic defenses

40. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Nonspecific Defenses (Part 6 - Inflammatory Response) Figure 20.10

41. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.13 Inflammation Figure 20.13

42. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Nonspecific Defenses: Fever Maintenance of a body temperature above 37.2 o C (99 o F) Pyrogens reset the hypothalamic thermostat and raise body temperature Pathogens, toxins, antigen-antibody complexes can act as pyrogens

43. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.10 Figure 20.10 Nonspecific Defenses (Part 7 - Fever)

44. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Forms of immunity Innate immunity Genetically determined Present at birth Acquired immunity Not present at birth Achieved by exposure to antigen Active immunity Passive immunity

45. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.14 Types of Immunity Figure 20.14

46. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Properties of immunity Specificity – activated by and responds to a specific antigen Versatility – is ready to confront any antigen at any time Memory – “remembers” any antigen it has encountered Tolerance – responds to foreign substances but ignores normal tissues

47. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings The immune system response Antigen triggers an immune response Activates T cells and B cells T cells are activated after phagocytes exposed to antigen T cells attack the antigen and stimulate B cells Activated B cells mature and produce antibody Antibody attacks antigen

48. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.15 Figure 20.15 An Overview of the Immune Response

49. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Major types of T cells Cytotoxic T cells (T C ) – attack foreign cells Helper T cells (T H ) – activate other T cells and B cells Suppressor T cells (T S ) – inhibit the activation of T and B cells

50. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Antigen presentation Antigen-glycoprotein combination appears on a cell membrane Called MHC proteins (Major Histocompatibility Complex) Coded for by genes of the MHC T-cells sensitive to the antigen are activated upon contact

51. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings MHC classes Class I – found on all nucleated cells Class II – found on antigen presenting cells and lymphocytes

52. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Lymphocytes respond to antigens bound to either class I or class II MHC proteins Antigen recognition T cell membranes contain CD markers CD3 markers present on all T cells CD8 markers on cytotoxic and suppressor T cells CD4 markers on helper T cells

53. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.16 Antigens and MHC Proteins Figure 20.16a

54. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.16 Antigens and MHC Proteins Figure 20.16b

55. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Activation of CD8 cells Responds quickly giving rise to other T cells Cytotoxic T cells – seek out and destroy abnormal cells Lymphotoxin Memory T C cells – function during a second exposure to antigen Suppressor T cells – suppress the immune response

56. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.17 Figure 20.17 Antigen Recognition and the Activation of Cytotoxic T Cells Animation: Cytotoxic T-cell activation PLAY

57. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Activation of CD4 T cells by antigens presented on class II MHC proteins Produces helper T cells and memory T cells Activated helper T cells Secrete lymphokines that coordinate specific and nonspecific defenses Enhance nonspecific defenses Stimulate the activity of NK cells Promote activation of B cells

58. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.18 Figure 20.18 Antigen Recognition and Activation of Helper T cells Animation: Antigen recognition and helper T cell activation PLAY

59. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.19 Figure 20.19 A Summary of the Pathways of T Cell Activation

60. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings B cell sensitization of activation Sensitization – the binding of antigens to the B cell membrane antibodies Antigens then displayed on B cell Class II MHC T H cells activated by same antigen stimulate B cell Active B cell differentiates into Memory B Cell or Plasma cell Plasma cells synthesize and release antibody

61. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.20 Figure 20.20 The Sensitization and Activation of B Cells Animation: B cells and antibody production PLAY

62. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Antibodies structure Antibodies are Y-shaped proteins consisting of: Two parallel polypeptide chains Heavy chains and light chains Constant region and variable region Antigen binding site

63. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.21 Antibody Structure Figure 20.21a

64. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.21 Antibody Structure Figure 20.21b

65. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.21 Antibody Structure Figure 20.21c, d

66. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Actions of antibodies include: Neutralization Agglutination and precipitation Activation of complement Attraction of phagocytes Opsinization Stimulation of inflammation Prevention of adhesion

67. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Classes of Antibodies (immunoglobins) IgG – resistance against many viruses, bacteria and bacterial toxins IgE – accelerates local inflammation IgD – found on the surface of B cells IgM – first type secreted after antigen arrives IgA – primarily found in glandular sec

68. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Primary and secondary antibody response Primary response Takes about two weeks to develop Produced by plasma cells Secondary response Rapid increase in IgG Maximum antibody titer app

69. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.22 Figure 20.22 The Primary and Secondary Immune Responses

70. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.23 Figure 20.23 An Integrated Summary of the Immune Response

71. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.25a, b Figure 20.25 The Course of the Body’s Response to Bacterial Infection

72. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Focus on Hormones of the Immune System Interleukins Increase T cell sensitivity Stimulate B cell activity, plasma formation, and antibody production Enhance nonspecific defenses Moderate the immune system Interferons Tumor Necrosis Factors (TNFs) slow tumor growth Colony Stimulating Factors (CSFs)

73. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Development of the Immune Response Immunological competence The ability to demonstrate an immune response after exposure to an antigen Fetuses receive immunity from the maternal bloodstream Infants acquire immunity following exposure

74. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Immune disorders Autoimmune disorders Immune response mistakenly targets normal cells Immunodeficiency diseases Immune system does not develop properly or is blocked

75. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Allergies Inappropriate or excessive immune response to allergens Immediate hypersensitivity (type I) Cytotoxic reactions (type II) Immune complex disorders (type III) Delayed hypersensitivity (type IV) Anaphylaxis Circulating allergen affects mast cells throughout body

76. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 20.26 The Mechanism of Anaphylaxis Figure 20.26

77. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Stress and the immune response Interleukin-1 released by active macrophages Triggers release of ACTH resulting in glucocorticoid release Moderates the immune response Lowers resistance to disease

78. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Stress can cause the following: Depression of the inflammatory response Phagocytic reduction Inhibition of interleukin secretion

79. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings The structure and function of lymphatic cells, tissues and organs The body’s nonspecific defenses and the components and mechanisms of each Specific resistance, cell-mediated immunity and antibody mediated immunity The role of the T cell, B cell and antibodies in specific immunity The origin, development, activation and regulation of normal resistance to disease The effects of stress on the immune system You should now be familiar with: