Question 1

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

Accepted Answer

T cells are trained to recognize foreign antigens only when they are presented in the context of the body's own MHC molecules. This is known as self-MHC restriction.

Question 2

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

Accepted Answer

In choice B, macrophages are fixed with paraformaldehyde before being exposed to the antigen, which prevents them from processing and presenting the antigen to T cells, thus making T-cell activation least likely.

Question 3

Place the class I processing pathway in the correct order:

Accepted Answer

The correct sequence for the class I processing pathway involves proteins being digested by the proteasome, followed by the importation of the resulting peptides into the ER by TAP. Within the ER, these peptides are loaded onto MHC class I molecules, which are then exported to the cell surface. This pathway is essential for presenting endogenous antigens to CD8+ T cells.

Question 4

In people infected with human cytomegalovirus, class I MHC and ? ₂-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?

Accepted Answer

Human cytomegalovirus inhibits the transporter associated with antigen processing (TAP), which is essential for the transport of peptides into the endoplasmic reticulum for loading onto MHC class I molecules. This inhibition leads to reduced presentation of viral antigens on the cell surface, helping the virus evade the immune system.

Question 5

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

Accepted Answer

Chloroquine increases the pH of lysosomes within cells, including antigen-presenting cells. This increase in pH can inhibit the processing and presentation of antigens, thereby affecting T-cell activation.

Question 6

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

Accepted Answer

The invariant chain (Ii) plays multiple roles in the immune system, including preventing peptide binding to MHC class II molecules in the ER, assisting in the folding of class II alpha and beta chains, directing class II molecules to the endocytic compartment, and serving as a substrate for proteases in the lysosome.

Question 7

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

Accepted Answer

The MHC class II molecule DM plays a crucial role in the removal of CLIP (class II-associated invariant chain peptide) from the MHC class II molecule, allowing other peptides to bind. If DM is nonfunctional, CLIP remains bound, preventing the binding of other peptides.

Question 8

Which of the following is an example of cross presentation?

Accepted Answer

Cross-presentation refers to the process where exogenous antigens are presented on MHC class I molecules, typically to activate CD8+ T cells.

Question 9

Of the antigen receptors listed here - T-cell receptor, B-cell receptor, MHC I, and MHC II - which would you describe as "promiscuous" in their ligand-binding activity?

Accepted Answer

The answer of Of the antigen receptors listed here -...

Question 10

Examine Figure 7-4.(in the text) Can you summarize, in two sentences maximum, what this figure demonstrates about MHC I-peptide antigen interactions?

Accepted Answer

The answer of Examine Figure 7-4.(in the text) Can you...

Question 11

You might have noticed that two people may respond to the same bacterial pathogen differently.Although "Person A" might only suffer a minor disease, "Person B" may take longer to clear the same pathogen.Argue how this discrepancy can be explained, at least in part, by the determinant selection model.

Accepted Answer

The answer of You might have noticed that two people...

Question 12

B-cell receptor and T-cell receptor diversity is generated through genomic rearrangement and gene editing mechanisms.Compare those mechanisms with mechanisms used to generate MHC diversity in an individual.How are the mechanisms the same, and how are they different?

Accepted Answer

The answer of B-cell receptor and T-cell receptor diversity is...

Question 13

Name the primary factor contributing to the observation that human genes found within the MHC locus are inherited as a set, which is described by geneticists as a linkage disequilibrium pattern of inheritance.

Accepted Answer

The answer of Name the primary factor contributing to the...

Question 14

You have two brothers and a sister, and your parents have different haplotypes.Are you more likely to be histocompatible with a sibling within your family or your parents?

Accepted Answer

The answer of You have two brothers and a sister,...

Question 15

Compare and contrast the holes-in-the-repertoire model and the determinant-selection model of immune responsiveness.

Accepted Answer

The answer of Compare and contrast the holes-in-the-repertoire model and...

Question 16

Name an advantage of presenting viral antigens by both the endogenous and exogenous pathways.

Accepted Answer

The answer of Name an advantage of presenting viral antigens...

Question 17

Suppose an individual is deficient in TAP (transporter associated with antigen processing).Is the deficiency MORE likely to produce symptoms of immune deficiency or autoimmunity in the person?

Accepted Answer

The answer of Suppose an individual is deficient in TAP...

Question 18

In your own words, explain how the immune system can activate CD8⁺ T-cells to eliminate intracellular pathogens (i.e., viruses) unless a dendritic cell happens to become infected.

Accepted Answer

The answer of In your own words, explain how the...

Question 19

Nonprotein antigens are not recognized by T cells.Is this statement true or false? Justify your answer.

Accepted Answer

The answer of Nonprotein antigens are not recognized by T...

Quiz 7: The Major Histocompatibility Complex and Antigen Presentation

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

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

Place the class I processing pathway in the correct order:

In people infected with human cytomegalovirus, class I MHC and ? ₂-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?

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

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

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

Which of the following is an example of cross presentation?

Of the antigen receptors listed here - T-cell receptor, B-cell receptor, MHC I, and MHC II - which would you describe as "promiscuous" in their ligand-binding activity?

Examine Figure 7-4.(in the text) Can you summarize, in two sentences maximum, what this figure demonstrates about MHC I-peptide antigen interactions?

B-cell receptor and T-cell receptor diversity is generated through genomic rearrangement and gene editing mechanisms.Compare those mechanisms with mechanisms used to generate MHC diversity in an individual.How are the mechanisms the same, and how are they different?

Name the primary factor contributing to the observation that human genes found within the MHC locus are inherited as a set, which is described by geneticists as a linkage disequilibrium pattern of inheritance.

You have two brothers and a sister, and your parents have different haplotypes.Are you more likely to be histocompatible with a sibling within your family or your parents?

Compare and contrast the holes-in-the-repertoire model and the determinant-selection model of immune responsiveness.

Name an advantage of presenting viral antigens by both the endogenous and exogenous pathways.

Suppose an individual is deficient in TAP (transporter associated with antigen processing).Is the deficiency MORE likely to produce symptoms of immune deficiency or autoimmunity in the person?

In your own words, explain how the immune system can activate CD8⁺ T-cells to eliminate intracellular pathogens (i.e., viruses) unless a dendritic cell happens to become infected.

Nonprotein antigens are not recognized by T cells.Is this statement true or false? Justify your answer.

Quiz 7: The Major Histocompatibility Complex and Antigen Presentation

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

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

Place the class I processing pathway in the correct order:

In people infected with human cytomegalovirus, class I MHC and ? 2-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?

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

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

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

Which of the following is an example of cross presentation?

Of the antigen receptors listed here - T-cell receptor, B-cell receptor, MHC I, and MHC II - which would you describe as "promiscuous" in their ligand-binding activity?

Examine Figure 7-4.(in the text) Can you summarize, in two sentences maximum, what this figure demonstrates about MHC I-peptide antigen interactions?

B-cell receptor and T-cell receptor diversity is generated through genomic rearrangement and gene editing mechanisms.Compare those mechanisms with mechanisms used to generate MHC diversity in an individual.How are the mechanisms the same, and how are they different?

Name the primary factor contributing to the observation that human genes found within the MHC locus are inherited as a set, which is described by geneticists as a linkage disequilibrium pattern of inheritance.

You have two brothers and a sister, and your parents have different haplotypes.Are you more likely to be histocompatible with a sibling within your family or your parents?

Compare and contrast the holes-in-the-repertoire model and the determinant-selection model of immune responsiveness.

Name an advantage of presenting viral antigens by both the endogenous and exogenous pathways.

Suppose an individual is deficient in TAP (transporter associated with antigen processing).Is the deficiency MORE likely to produce symptoms of immune deficiency or autoimmunity in the person?

In your own words, explain how the immune system can activate CD8+ T-cells to eliminate intracellular pathogens (i.e., viruses) unless a dendritic cell happens to become infected.

Nonprotein antigens are not recognized by T cells.Is this statement true or false? Justify your answer.

In people infected with human cytomegalovirus, class I MHC and ? ₂-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?

In your own words, explain how the immune system can activate CD8⁺ T-cells to eliminate intracellular pathogens (i.e., viruses) unless a dendritic cell happens to become infected.