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 3 The Lymphatic System and Immunity

2. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings SECTION 22-4 Specific Defenses

3. 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

4. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.14 Types of Immunity Figure 22.14

5. 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

6. 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

7. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.15 Figure 22.15 An Overview of the Immune Response

8. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings SECTION 22-5 T cells and Cell-mediated Immunity

9. 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

10. 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

11. 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

12. 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

13. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.16 Antigens and MHC Proteins Figure 22.16

14. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.16 Antigens and MHC Proteins Figure 22.16a

15. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.16 Antigens and MHC Proteins Figure 22.16b

16. 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

17. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.17 Figure 22.17 Antigen Recognition and the Activation of Cytotoxic T Cells

18. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.17 Figure 22.17 Antigen Recognition and the Activation of Cytotoxic T Cells Animation: Cytotoxic T Cell Activation PLAY

19. 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

20. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.18 Figure 22.18 Antigen Recognition and Activation of Helper T cells Animation: Antigen Recognition and Helper T Cell Activation PLAY

21. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 22.19 Figure 22.19 A Summary of the Pathways of T Cell Activation