Question 1

Which of the following best describes the role of Class I MHC proteins in the immune response?

Accepted Answer

They are displayed by all nucleated cells and present endogenous antigens to CD8 cytotoxic T cells.

Question 2

A patient receives a mismatched blood transfusion and develops a rapid immune response. Which type of hypersensitivity is this, and which immunoglobulins are primarily involved?

Accepted Answer

Subacute hypersensitivity; IgM and IgG

Question 3

Which of the following is a key function of regulatory T (Treg) cells in the immune system?

Accepted Answer

Suppressing self-reactive lymphocytes and preventing autoimmune reactions

Question 4

During the activation of a naive T cell, which two signals are required for full activation and clonal selection?

Accepted Answer

Antigen binding and co-stimulation

Question 5

A patient with HIV is found to have a severely reduced number of CD4 cells. Which aspect of their immune response is most directly compromised?

Accepted Answer

Activation of both humoral and cellular adaptive immunity

Question 6

Which cytokine is primarily responsible for stimulating the rapid division of activated T cells and is considered a key growth factor?

Accepted Answer

Interleukin-2 (IL-2)

Question 7

Which of the following best explains why cytotoxic T (TC) cells do not attack healthy self-cells?

Accepted Answer

They ignore self-antigens displayed on Class I MHC proteins.

Question 8

A patient develops muscle weakness due to antibodies attacking acetylcholine receptors at the neuromuscular junction. Which autoimmune disease is this?

Accepted Answer

Myasthenia gravis

Question 9

Which of the following mechanisms is used by cytotoxic T cells to induce apoptosis in target cells?

Accepted Answer

Release of perforins to form pores and granzymes to trigger apoptosis

Question 10

A patient experiences anaphylactic shock after a bee sting. Which immune mechanism is primarily responsible for this reaction?

Accepted Answer

IgE-mediated release of histamine from mast cells

Question 11

Which of the following best describes the process of MHC restriction?

Accepted Answer

CD4 cells recognize antigens only on Class II MHC, while CD8 cells recognize antigens only on Class I MHC.

Question 12

Which of the following is a real-world example of delayed hypersensitivity?

Accepted Answer

Allergic contact dermatitis from poison ivy

Question 13

A patient with a genetic defect in adenosine deaminase (ADA) is unable to mount effective immune responses. What is the most likely diagnosis?

Accepted Answer

Severe combined immunodeficiency (SCID)

Question 14

Which of the following best explains why immunosuppressive therapy after organ transplantation increases the risk of infection?

Accepted Answer

The therapy suppresses the patient’s immune system, reducing defense against bacteria and viruses.

Question 15

Which subset of helper T cells is primarily involved in defending against parasitic worms and promoting allergic responses?

Accepted Answer

TH2 cells

Question 16

Which of the following is a function of gamma interferon in the immune response?

Accepted Answer

Enhancing the killing power of macrophages

Question 17

A patient with systemic lupus erythematosus (SLE) is experiencing tissue damage due to immune complex deposition. Which type of hypersensitivity is this?

Accepted Answer

Immune complex (subacute) hypersensitivity

Question 18

Which of the following best describes the process by which dendritic cells can activate CD8 cells with exogenous antigens?

Accepted Answer

Dendritic cells engulf dying infected cells and display their endogenous proteins on Class I MHC.

Question 19

Which of the following is a possible cause of autoimmunity due to the appearance of new self-antigens?

Accepted Answer

Gene mutations or hapten attachment altering self-antigens

Question 20

Which of the following best explains why antihistamines are effective in treating symptoms of immediate hypersensitivity?

Accepted Answer

They block the action of histamine released from mast cells, reducing vasodilation and vascular permeability.

Cellular Immune Response and Disorders of Immunity

Study Guide - Practice Questions

Study Guide - Flashcards