1. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Fundamentals of Anatomy & Physiology SIXTH EDITION Frederic H. Martini PowerPoint ® Lecture Slide Presentation prepared by Dr. Kathleen A. Ireland, Biology Instructor, Seabury Hall, Maui, Hawaii Chapter 22, part 2 The Lymphatic System and Immunity

2. 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

3. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.8 The Thymus Figure 22.8a-c

4. 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

5. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.9 The Spleen Figure 22.9a-c

6. 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

7. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings SECTION 22-3 Nonspecific Defenses

8. 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

9. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Figure 22.10 Nonspecific Defenses (Part 1 - Physical Barriers)

10. 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

11. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Nonspecific Defenses (Part 2 - Phagocytes) Figure 22.10

12. 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

13. 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

14. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Figure 22.10 Nonspecific Defenses (Part 3 - Immunological Surveillance)

15. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.11 Figure 22.11 How Natural Killer Cells Kill Cellular Targets

16. 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

17. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Nonspecific Defenses (Part 4 - Interferons) Figure 22.10

18. 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

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

20. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Figure 22.10 Nonspecific Defenses (Part 5 - Complement System)

21. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.12 Complement Activation Figure 22.12

22. 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

23. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Nonspecific Defenses (Part 6 - Inflammatory Response) Figure 22.10

24. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.13 Inflammation Figure 22.13

25. 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

26. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.10 Figure 22.10 Nonspecific Defenses (Part 7 - Fever)