1. Chapter 15: The Adaptive Immune Response

2. General Characteristics of the Adaptive Immune Response
Involves specialized WBC’s known as lymphocytes
Response is highly specific (molecular specificity)
Response generates memory
Can discriminate between self and non-self (tolerance)

3. Overview of the Adaptive Immune Response

4. Anatomy of the Lymphoid System
Lymphatic Vessels
form lymph
Secondary lymphoid Organs
Lymph nodes, spleen, tonsils, peyer’s patches
Primary Lymphoid Organs
Bone marrow and thymus

5. Peyer’s Patch is example of secondary lymphoid organ

6. Lymphocytes are responsible for the adaptive immune response

7. What promotes an immune response?
Antigens
Any molecule that reacts with antibody, B cell receptor or T cell receptor
Composition is usually proteins or polysaccharides
Foreign substance with MW of 10,000 daltons
Examples of antigens: bacterial capsules, cell walls, flagella, toxins of bacteria

8. Antibodies bind antigens

9. Small molecules are not recognized as antigens until bound to another

10. How are antigens recognized?
Self markers also known as MHC markers
MHC (major histocompatibility complex)
MHC Class I-produced by all body cells
MHC Class II-produced by dendritic cells, B cells, and macrophages
These cells are also called antigen presenting cells (APCs)

11. How are B cells activated?

12. B cell activation by Helper T cell

13. Structure of an antibody

14. There are 5 classes of antibodies
IgM
IgG
IgA
IgE
IgD

15. Immunoglobulins

16. Naïve B cells produce IgM, then IgG antibodies

17. Primary and secondary response to antigen

18. What can happen when antibody binds antigen?

19. T-independent antigens activate B-cells without T cells

20. Let’s look at the T cells
Have own T cell receptor (TCR)
Do not make antibodies
Must recognize MHC markers which “present” antigen

21. T cells differ from B cells
Must use MHC markers on host cells to recognize antigens

22. Antigen recognition by T cells occurs with MHC:TCR binding

23. How are T cells activated?

24. Effector functions of Cytotoxic T cells

25. Effector function of Helper-T cells

26. Effector function of Helper-T cells

27. Natural Killer Cells…lymphocyte but not a T cell

28. Antibody dependent cell mediated cytotoxicity