Review the Concepts

1. Describe the ways in which each of the following pathogens can disarm their host’s immune system or manipulate it to their own advantage:

  1. Pathogenic strains of Staphylococcus

  2. Enveloped viruses

2. Trace the movement of leukocytes as they perform their functions throughout the body.

3. Identify the major mechanical and chemical defenses that protect internal tissues from microbial attack.

4. Compare and contrast the classical pathway of complement activation with the alternative pathway.

5. What evidence led Emil von Behring to discover antibodies and the complement system in 1905?

6. What is opsonization? What is the role of antibodies in this process?

7. In B cells, what mechanism ensures that only rearranged V genes are transcribed?

8. What prevents further rearrangement of immunoglobulin heavy-chain gene segments in a pre-B cell once a productive heavy-chain rearrangement has occurred?

9. How and why do B cells undergo a class switch from producing IgM antibodies to any of the other Ig isotypes?

10. What biochemical mechanism underlies affinity maturation of the antibody response?

1133

11. Compare and contrast the structures of class I and class II MHC molecules. What kinds of cells express each class of MHC molecule? What are their functions?

12. Describe the six steps in antigen processing and presentation via the class I MHC pathway.

13. Describe the six steps in antigen processing and presentation via the class II MHC pathway.

14. What prevents self-reactive T cells from leaving the thymus?

15. Explain why T-cell–mediated autoimmune diseases are associated with particular alleles of class II MHC genes.

16. How are antigen-presenting cells and helper T cells involved in B-cell activation?

17. Outline the events in the innate and adaptive immune responses, from when a pathogen invades to clearance of the pathogen.

18. Define passive immunization and give an example.

19. How would you design a vaccine that protects against HIV infection without the possibility of infecting the patient?

20. The annual flu shot is composed of either live attenuated influenza virus or influenza subunits (the envelope proteins neuraminidase and hemagglutinin). How does the annual flu shot protect you against infection?

21. Design a laboratory protocol to develop a monoclonal or polyclonal antibody against a protein of interest.

22. Consider a person without any functioning plasma cells. What effects would this condition have on the person’s adaptive immune system? Innate immune system?