Chapter 4

Question 1

A(n) ____ is a molecule that is used by immune cells for communication.

Answer 1

All of the above

Question 2

Which of the following is NOT a property of cytokines?

Answer 2

Induce cell motility

Question 3

______ are responsible for recruiting immune cells to a specific location within the body, organ, or tissue.

Answer 3

Chemokines

Question 4

The activity of most cytokines is BEST described as:

Answer 4

Both A and B: Autocrine and Paracrine

Question 5

What determines if a particular cell will be acted up on by a cytokine?

Answer 5

Presence or absence of a cytokine receptor

Question 6

IL-2 acts on several cell types thus regulating multiple immune processes. IL-2 is said to be:

Answer 6

pleiotropic.

Question 7

You are a new member of a graduate research lab. Your research is to study the effects of a novel cytokine TNF-mu (TNF-μ). During the course of your research, you discover that TNF-μ induces monocyte maturation, inhibits eosinophil development, and begins a signaling cascade that promotes histamine release. What term best describes the action of TNF-μ on eosinophils?

Answer 7

Antagonistic

Question 8

B-cell proliferation is triggered by IL-2, IL-4, and IL-5. Each of these cytokines is secreted by activated TH cells thus their action is:

Answer 8

redundant.

Question 9

Which of the following is an example of antagonism?

Answer 9

IFN-ɣ prevents class switching in plasma cells by binding IL-4.

Question 10

Chemokines often show redundancy in their signaling. Why might redundancy be beneficially in multicellular organisms to starting certain immune responses?

Answer 10

A, B, and C

Question 11

Cytokines are grouped into functional families. How many families of cytokines are identified to date?

Answer 11

6

Question 12

Which cytokine family is responsible for promoting inflammation?

Answer 12

Interleukin 1 family

Question 13

IRAK is a cytokine receptor activated kinase that binds MyD88 and TRAF6. The IRAK-TRAF6 complex activates TAK1 protein that will activate either the MAP kinase cascade or the NF-κB pathway. Which family of cytokine receptors can activate IRAK?

Answer 13

Interleukin 1 family

Question 14

IL-2, GM-CSF, erythropoietin, prolactin, and IL-12 are representatives of which cytokine family?

Answer 14

Hematopoietin family

Question 15

Which family of cytokines was the first to be discovered?

Answer 15

Interferons family

Question 16

Members of type I and type III interferon are responsible for controlling:

Answer 16

Both A and C

Question 17

Which family of cytokine receptors uses the Janus activated kinase (JAK) family of tyrosine kinases?

Answer 17

Interferons family

Question 18

Which family of cytokines regulates target-cell development, proliferation, or death?

Answer 18

Tumor Necrosis Factor family

Question 19

This family of cytokines is the most recently discovered and contains cytokines that contribute to both innate and adaptive immunity.

Answer 19

Interleukin 17 family

Question 20

_______ are proteins that inhibit the activity of various cytokines.

Answer 20

Cytokine antagonists

Question 21

Epstein-Barr virus produces an IL-10 homologue. What is the purpose of the IL-10 homologue?

Answer 21

The IL-10 homologue binds to the cell receptor to prevent cytokines from triggering an inflammatory response.

Question 22

Variola virus, the causative agent of small pox, produces soluble TNF receptors. What advantage does the production of a TNF receptor have for avoiding immune response?

Answer 22

TNF represents a family of soluble cytokines. By producing soluble receptors that bind cytokines, then the cytokine effector response is eliminated and only a limited immune response will occur.

Question 23

Septic shock is caused by:

Answer 23

lipid A (an endotoxin).

Question 24

A cytokine storm, or hypercytokinemia, is a condition where cytokines are released that trigger the release of other cytokines to develop a positive feedback loop. It is thought that the 1917–1918 Influenza pandemic induced a cytokine storm in its victims. Which of the following mechanisms would be BEST to stop the positive feedback loop created by a cytokine storm?

Answer 24

The use of soluble antagonists to bind membrane-bound cytokine receptors

Question 25

Several drugs have been developed over the past decade that target and bind to specific cytokines (e.g., TNF-α). What detrimental health effects result from blocking cytokines?

Answer 25

Both A and B are potential concerns.