Deck 22: Factors That Influence the Immune Response

Question 1

How do CD8 regulatory T cells identify CD4 cells that should be killed?

A) FasL is cleaved from CD4 T cell.
B) Qa-1 is present on CD4 T cell surface.
C) The high affinity IL-2 receptor is stimulated.
D) Antigen expression is required on MHC class II molecules.

Answer 1

Qa-1 is present on CD4 T cell surface.

Question 2

What is the difference between an idiotype and an idiotope?

A) Idiotopes are on the antibody and idiotypes are on the antigen.
B) Idiotopes can only react with T cells and idiotypes can only react with B cells.
C) Idiotopes are an amino acid sequence, and idiotypes are groups of idiotopes.
D) Idiotopes and idiotypes have the same sequence but in different locations on the antibody.

Answer 2

Idiotopes are an amino acid sequence, and idiotypes are groups of idiotopes.

Question 3

Which methods of antigen administration elicit a vigorous immune response?
I. Intravenous
II. Intramuscular
III. Subcutaneous

A) I only
B) III only
C) I and II
D) II and III
E) I, II, and III

Answer 3

II and III

Question 4

Antigen-induced cell death (AICD) is mediated by:
I- Fas:FasL interactions
II- Perforin and granzymes
III- TNF-mediated cell death

A) I only
B) III only
C) I and II
D) II and III
E) I, II, and III

Question 5

How does the "hole in the T cell repertoire" model explain why some individuals may fail to respond to an antigen?

A) MHC class II molecules differ in their ability to bind and process antigen.
B) The TCR is lacking appropriate accessory molecules to fully transduce signals.
C) Some individuals lack a lymphocyte with a TCR that recognizes a specific antigen.
D) Antigen is inappropriately presented on MHC class I molecules rather than class II molecules.

Question 6

Immune responses to idiotypes located outside the complementarity-determining regions (CDRs) result in:

A) Increases in autoantibody production
B) Downregulation of autoreactive B cells
C) Increases in activated regulatory T cells
D) Downregulation of MHC class II molecules on APCs

Question 7

Defects in Fas:FasL engagement and signaling may contribute to which disease?

A) Graves' disease
B) Rheumatoid arthritis
C) Type II diabetes mellitus
D) Systemic lupus erythematosus (SLE)

Question 8

What is the immune response to high doses of antigen?

A) T cells are inactivated.
B) B cells are inactivated.
C) NK cells are inactivated.
D) Macrophages are inactivated.

Question 9

Which of the following is the outcome of T cell interaction with immature dendritic cells that do not express costimulatory molecules?

A) Anergic T cell response
B) Only CD8 T cells respond
C) Only CD4 T cells respond
D) Uncontrolled T cell response

Question 10

What is the outcome of matrilysin cleaving FasL from an activated T cell?

A) Soluble FasL is degraded and the activated T cell survives.
B) Soluble FasL binds to Fas and triggers the death of the activated T cell.
C) Soluble FasL binds to Fas and triggers the death of the regulatory T cell.
D) Soluble FasL is disseminated and causes widespread cell death in both immune cells and infected host cells.