Chapter 3 Review Questions

Question 1

1. Give three examples of APCs: _____, _____________ and ___B-lymphocytes____. Which one of these are also referred to as “professional” APCs? ___ cells.
2. MHC molecules can only display ____________ fragments of the antigens.
   a. Carbohydrate b. ____ c. Nucleic acids d. lipids e. RNA
3. Which peptide blocks the antigen-binding cleft of class II molecules during processing (i.e. before it is displaced and antigen binds)?
   a. DM b. TAP c. ____
4. CD4 cells only recognize class ___ molecules, which allows for eradication of _________ [(intracellular (cytoplasmic) or extracellular (vesicular)] microbes after recognition and activation; CD8 cells only recognize class __ molecules, which allows for eradication of __________ [(intracellular (cytoplasmic) or extracellular (vesicular)] microbes after recognition and activation.

Answer 1

1. Macrophages, Dendritic cells, and B Lymphocytes
   Dendritic cells
2. Peptides
3. CLIP
4. II, Extracellular
   I, Intracellular

Question 2

5. Human leukocyte antigen (HLA) is the other name for _______.
6. A process where one cell type presents antigens of another cell and activates T lymphocytes specific for that cell type is called ___cross presentation/cross priming______.
7. The MHC class II molecule is made of two chains:__________ and ________.
8. A specific part of the antigen recognized by the immune system, specifically by antibodies, B cells and T cells is called an ____ (antigenic determinant) ______.

Answer 2

5. Human MHC Molecule
6. Cross Presentation/Cross Priming
7. Alpha and Beta
8. Epitope

Question 3

9. T cells are being restricted to recognize antigen presented by the MHC molecules only. This is called ___.
10. HLA-A, HLA-B and HLA-C are the gene clusters that make up MHC class ____ and HLA-DP, HLA-DQ and HLA-DR make up MHC class ___.
11. Define codominance __and “polymorphic”
12. All cells express MHC molecules except these cells: ____________.

Answer 3

9. MHC Restriction
10. I, II
11. Great amounts of variation in the expression of these molecules
12. Bothe maternal and paternal strands of chromosomes are expressed equally
    Mature Red Blood Cells (RBCs)

Question 4

13. Having the same exact MHC genes among individuals is highly unlikely except in_____________.
14. The cleft of MHC class __ is larger and can bind to a peptide size of about 10-30 amino acid residues.
15. The peptide binding portion of MHC I is __and ____. CD8 binds to the ____ portion of the MHC I molecule.
16. The structure that removes the CLIP portion of the invariant chain is _____.

Answer 4

13. Identical Twins
14. II
15. alpha 1 and alpha 2
    alpha 3
16. DM

Question 5

True/False. Please correct the false statement.
17. An MHC molecule without a peptide is highly unstable and will be degraded. ______

18. Class II MHC molecules are always present. __
19. Each MHC molecule displays many peptides at a time. __
20. MHC molecule has broad specificity for the peptides they bind to. ___

Answer 5

17. T
18. F, only when there is an infection
19. F, only one peptide at a time
20. T

Question 6

III. Rearrange the following processes in the correct order:

1. Migration of a dendritic cell:
   a. Antigen presentation
   b. Maturation of DC
   c. Loss of adhesiveness
   d. Antigen capture
   e. Migration
2. MHC protein synthesis and display of peptide:
   a. Antigen presentation
   b. Association of peptide to MHC
   c. Processing of extracellular antigen
   d. Synthesis of MHC molecule
3. MHC protein synthesis and display of peptide:
   a. Display of MHC with antigen
   b. Transport of peptide into endoplasmic reticulum
   c. Assembly of peptide to MHC
   d. Ubiquitination
   e. Antigen in cytosol

Answer 6

1. d c e b a
2. c d b a
3. e d b c a