Cytokines and Cytokine Receptors

Question 1

Hematopoietic, lymphoid, and inflammatory cells communicate via the production and synthesis of -?

Answer 1

Cytokines

Question 2

Cytokines are low weight ________ or _________, which are produced by lymphocytes.

Answer 2

Proteins or Glycoproteins

Question 3

Cytokines can be classified as __________ (cytokines produced by leukocytes, of which there are at least 37) or _________ (chemoattractants for chemotaxis).

Answer 3

Interleukins

Chemokines

Question 4

True or False: The binding of interleukines along general receptors of cells can initiate or suppress signals.

Answer 4

False, must be to their specific receptors on cells

Question 5

In the presence of a small concentration of cytokines, will they be able to bind to their receptors in order to initiate cell signaling?

Answer 5

Yes, as cytokines have a high affinity for their specific receptors

Question 6

Define autocrine signaling.

Answer 6

The production of a cytokine by a cell, for it to only bind to its specific receptor on the same cell for stimulation

Question 7

Define paracrine signaling.

Answer 7

The production of a cytokine by a cell, for it to bind to its specific receptor on nearby cell

Question 8

Define endocrine signaling.

Answer 8

The production of a cytokine by a cell, for it to bind to its specific receptor on a cell in a distant part of the body

Question 9

If IL-4 can lead to activation and differentiation of B cells, class switching of plasma cell immunoglobulins, and activate Mast cells to proliferate, what biological effect is this?

Answer 9

Pleiotropy

Question 10

If both IL-10 and IL-4 are able to suppress inflammatory mechanisms to terminate those processes by binding to Macrophages and inducing the same response, what is this biological effect called?

Answer 10

Redundancy

Question 11

If both IL-4 and IL-5 are required for B cell proliferation, what biological effect is this?

Answer 11

Synergism

Question 12

If IFN gamma can be secreted to inhibit and block the binding of IL-4 to B cells, what is this biological effect called?

Answer 12

Antagonism

Question 13

True or False: Viral proteins that share similar, if not exact, chemical characteristics to cytokines, can bind to those specific cytokine receptors along any cell.

Answer 13

True

Question 14

Why are cytokines capable of binding to any cell?

Answer 14

They will have a high affinity for their specific receptors, which could be produced on any number of cells in the body

Question 15

Of the three - Growth factors, Cytokines, Hormones - which of the following are produced based on external stimuli?

Answer 15

Cytokines and Hormones

Question 16

Of the three - Growth factors, Cytokines, and Hormones - which of the following are able to participate in autocrine, paracrine, and endocrine signaling?

Answer 16

Cytokines

Question 17

Of the three - Growth factors, Cytokines, and Hormones - which of the following can be produced by a variety of tissues, and are produced continuously?

Answer 17

Growth factors

Question 18

Of - the three - Growth factors, Cytokines, and Hormones - which of the following is produced by specialized glands and are long-lived?

Answer 18

Hormones

Question 19

What are some functions associated with cytokines?

Answer 19

Cellular and humoral immunity, Inflammatory induction, Hematopoietic regulation, Regulation of cells, Regulation of inflammatory responses (time and intensity), and Wound healing

Question 20

IFN alpha, TGF beta, TNF alpha, IL-1, IL-6, and IL-12, are produced by -?

Answer 20

Macrophages

Question 21

Th2 cells are responsible for the production of what cytokines?

Answer 21

IL-4 and IL-5

Question 22

Dendritic cells produce this cytokine, which activates NK cells, and influences the adaptive immune response, to promote Th1 cells?

Answer 22

IL-12

Question 23

IFN alpha is associated with inducing an _______ state, and promoting B cell proliferation and differentiation, after production from ____________.

Answer 23

Antiviral

Macrophages

Question 24

What cytokines are released into circulation to induce increased liver production of acute phase proteins during the inflammatory response?

Answer 24

TNF alpha, IL-1, and IL-6

Question 25

What cytokine, produced from macrophages and other cell types, is associated with inhibiting T cell and B cell proliferation, as well as inhibiting macrophages?

Answer 25

TGF beta

Question 26

What interleukin acts as an eosinophil activator? What cells produce this cytokine?

Answer 26

IL-5 by Th2 cells

Question 27

T cells produce IL-2, which has a variety of functions. What are some of those functions?

Answer 27

T and B cell proliferation, and NK cell activation

Question 28

While both IFN alpha and IFN beta promote the expression of MHC __ receptors, IFN gamma is associated with promoting the expression of -?

Answer 28

IFN alpha/ IFN beta = MHC I molecules | IFN gamma = MHC I and II molecules

Question 29

``` Which of the following cells does not secrete cytokines capable of activating NK cells? A) T cells B) Th2 cells C) Fibroblasts D) Macrophages ```

Answer 29

B) Th2 cells

Question 30

What functions are associated with the cytokine produced by both Th2 cells and Mast cells?

Answer 30

IL-4 = Promotes Th2 differentiation and isotype switching to IgE

Question 31

``` What cytokine is produced by endothelial cells in response to inflammatory processes? A) IL-6 B) TNF alpha C) IFN beta D) IL-1 E) Two of the above ```

Answer 31

E) Two of the above (both IL-1 and IL-6)

Question 32

What protein groups are associated with cytokines?

Answer 32

Hematopoietins, Interferons, Chemokines, and TNF Family

Question 33

How many protein families of receptors are associated with cytokines? What are they?

Answer 33

4 | Ig Superfamily, Class I (hematopoietin), Class II (interferon), and TNF receptors

Question 34

IL-1 will travel to the liver and bind to hepatocytic receptors, which are members of what protein family?

Answer 34

Ig Superfamily protein receptors

Question 35

Expressed on the cell surface, this family of receptors will be recognized by IL-2, IL, 12, G-CSF, GH, and Prolactin, among other ligands? What subfamilies are associated with this class?

Answer 35

Class I (hematopoietin) protein receptors GM-CSF receptor subfamily (common beta subunit) IL-2 receptor subfamily (common gamma subunit) IL-6 receptor subfamily (common gp130 subunit)

Question 36

IL-10 will recognize protein receptors of what family? What other cytokines will be associated with this protein receptors family as well?

Answer 36

``` Class II (interferon) protein receptors IFN alpha, beta, and gamma, ```

Question 37

What receptor family will be associated with TNF alpha and TNF beta?

Answer 37

TNF protein receptors

Question 38

True or False: Composed of several subunits, cytokine receptor subunits will have separate functions for cytokine binding recognition and initiating intracellular signaling pathways.

Answer 38

False, as most cytokine receptors have only a few subunits, not several

Question 39

Will a cytokine have a strong or weak affinity for a double signaling subunit, cytokine receptor?

Answer 39

Weak, and only upon binding will it have an increased affinity

Question 40

True or False: A common signaling subunit is likely the cause for both redundancy and synergism.

Answer 40

False, it is either redundancy (binding with the second common subunit leads to the same signal produced) or antagonism (cytokine competition for the same subunit)

Question 41

If IL-3, IL-5 and GM-CSF are able to affect hematopoiesis, induce proliferation of neutrophils and degranulation of basophils, then they would act in a _______ manner.

Answer 41

Redundant

Question 42

IL-2 subfamily receptors have _ chains. What are they?

Answer 42

3 | Alpha, beta, and gamma

Question 43

How many forms of the IL-2 receptors are there? Which form will have the highest affinity for IL-2?

Answer 43

3 | Monomeric (lowest affinity), Dimeric, and Trimeric (highest affinity)

Question 44

Chemokines, which are small __________, regulate the adhesion process and chemotaxis during inflammation, as well as during _________ conditions.

Answer 44

Polypeptides | Homeostatic

Question 45

Chemokines, which are made in peripheral _______ ______ cells, the _____ _______, or even other tissues, will be induced by the presence of TNF ______.

Answer 45

Peripheral Lymphoid Tissue cells the Bone Marrow TNF alpha

Question 46

What other roles, beside regulation of leukocyte extravasation and chemotaxis, are chemokines associated with?

Answer 46

Wound healing, angiogenesis, and cardiac and neural tissue development

Question 47

What subfamilies are there for chemokines?

Answer 47

C, CC, CXC, CX3C chemokine superfamilies

Question 48

How are the subfamilies or branches of chemokines divided?

Answer 48

Based on their cysteine motif, or the pattern of cysteine residues in the ligands

Question 49

C chemokines are associated with what structure?

Answer 49

2 cysteines bound side by side via disulphide bonds

Question 50

CC chemokines are associated with what structure?

Answer 50

2 cysteines are bound one after another, with their own side chains

Question 51

CXC chemokines are associated with what structure?

Answer 51

2 cysteines are separated by a single aa between them

Question 52

CX3C chemokines are associated with what structure?

Answer 52

2 cysteines are separated by 3 aa's between them, as well as with a mucin domain attached

Question 53

Chemokine receptors are similar in structure to _ ______ __________ receptors, that are composed of _ transmembrane units and 3 intracellular subunits (alpha, beta, and gamma)

Answer 53

G couples protein (GPCRs)

Question 54

What chemokine is produced as a result of the interaction between IL-1 and IL-6 during inflammatory processes?

Answer 54

IL-8

Question 55

What type of chemokine receptor will bind CXC chemokines?

Answer 55

CXCR, or CXC receptors

Question 56

What type of chemokine receptor will bind CX3C chemokines?

Answer 56

CX3CR, or CX3C receptors

Question 57

chemokines?

Answer 57

CCR, or CC receptors

Question 58

What pro-inflammatory chemokines are associated with binding to CCRs?

Answer 58

MIP-1 alpha and MIP-1 beta, to CCL3 and CCL4 respectively

Question 59

What pro-inflammatory chemokine is associated with binding to CX3CRs?

Answer 59

IL-8, to CX3CL8