Chapter 8

Question 1

MHC molecules:

Answer 1

are recognized by T cells.

Question 2

A mutation in which part of a viral protein might allow the virus to evade the adaptive immune response because it MHC binding?

Answer 2

An anchor residue

Question 3

MHC polymorphisms tend to cluster:

Answer 3

in the peptide-binding groove.

Question 4

How many different MHC classical class I proteins does each nucleated cell in a human heterozygous at the MHC locus express?

Answer 4

Six

Question 5

Which of the following would be the MOST likely source of a peptide bound to an MHC class I molecule?

Answer 5

The cytoplasm

Question 6

One way a developing fetus is protected from attack by the maternal immune system is:

Answer 6

expression on nonclassical class I molecules.

Question 7

Which of the following is NOT a mouse MHC gene?

Answer 7

DP

Question 8

Peptide binding diversity is increased by:

Answer 8

Both A and B

Question 9

Your chances of having the same MHC haplotype as your sibling are:

Answer 9

1:4.

Question 10

The human MHC locus is one of the most polymorphic regions of the genome. What does this mean?

Answer 10

There are many different alleles of these genes.

Question 11

MHC diversity ultimately affects the:

Answer 11

variety of peptides that bind to MHC.

Question 12

Which of the following BEST represents the relationship of polypeptide units in MHC class II?

Answer 12

Only α and β chains from the same gene can pair with each other.

Question 13

Tasmanian devils are a largely inbred population with little diversity in the MHC. Which of the following would be a likely outcome of this?

Answer 13

They would be at higher risk of infection.

Question 14

Which of the following cell types would be LEAST likely to express MHC class II?

Answer 14

T cells

Question 15

Which of the following cell types would be MOST likely to express MHC class I?

Answer 15

All of the above

Question 16

Which of the following is the BEST example of self-MHC restriction of T cells?

Answer 16

A T-cell clone only recognizes foreign peptides when presented by self MHC.

Question 17

Under which of the following conditions would T-cell activation be LEAST likely to occur?

Answer 17

Macrophages are fixed with paraformaldehyde, then incubated with antigen, then incubated with antigen-specific T cells.

Question 18

Place the class I processing pathway in the correct order:

Answer 18

Proteins are digested by the proteasome > peptides are imported into the ER by TAP > peptides are loaded onto MHC class I > class I is exported to the cell surface

Question 19

In people infected with human cytomegalovirus, class I MHC and β2-microglobulin are produced, but very little mature class I MHC is found at the cell surface. Inhibition of which of the following molecules by human cytomegalovirus may account for this phenomenon?

Answer 19

TAP

Question 20

T-cell activation can be inhibited by treating antigen-presenting cells with chloroquine. What is chloroquine’s mechanism of action?

Answer 20

It increases the pH of the lysosome.

Question 21

What is the role of the invariant chain (Ii)?

Answer 21

All of the above

Question 22

A mutation that renders the MHC class II molecule DM nonfunctional would likely lead to:

Answer 22

cells with class II MHC only bound with CLIP.

Question 23

Which of the following is an example of cross-presentation?

Answer 23

An exogenous peptide being presented on MHC class I