Cytokines

Question 1

are cytokines involved in a specific aspect of the immune response?

Answer 1

nope; involved throughout entire thing

Question 2

what are cytokines?

Answer 2

chemical messengers that allow for communication between cells of the immune system

Question 3

what are cytokines secreted by? what is their general function

Answer 3

secreted by cells; have multiple targets and cause different responses

Question 4

what are the 2 major kinds of cytokines?

Answer 4

1. interleukins

2. chemokines

Question 5

what do interleukins (IL) do?

Answer 5

communicate between WBCs

Question 6

what do chemokines do?

Answer 6

attract cells to the site of infection

Question 7

what are the 3 types of signalline that cytokines can utilize?

Answer 7

1. endocrine
2. paracrine
3. autocrine

Question 8

describe endocrine cytokine signaling

Answer 8

cytokine is released into bloodstream to travel to target (long distance like fever); is the least common signaling method

Question 9

describe paracrine cytokine signaling

Answer 9

cytokine will act locally; most common method

Question 10

describe autocrine cytokine signaling

Answer 10

cytokine will act on the CELL that secreted it

Question 11

do all cytokines utulize only one method of signaling?

Answer 11

nope; can utilize multiple routes

Question 12

what are the 4 steps of cytokine signaling?

Answer 12

1. stimulus that causes release of a cytokine
2. travels to targetcells where it binds to receptor
3. results in activation of intracellular signaling pathway
4. results in biological effect

Question 13

what do cytokines NEED to work on target cells?

Answer 13

a receptor

Question 14

describe the effects of cytokines

Answer 14

every cytokine has its own specific effect on its target

Question 15

what are the 5 cytokine attributes?

Answer 15

1. pleiotropy
2. redundancy
3. synergy
4. antagonism
5. cascade induction

Question 16

describe the pleiotropy attribute of cytokines

Answer 16

a single cytokine can induce different biological effects depending on the target cell

Question 17

describe the redundancy attribute of cytokines

Answer 17

two or more cytokines can mediate similar functions

Question 18

describe the synergy attribute of cytokines

Answer 18

the combined effect of two cytokines is greater than the additive effect of individual cytokines; must be secreted together in order to occur

Question 19

describe the antagonism attribute of cytokines

Answer 19

the effects of one cytokine can inhibit the effects of another; can turn the immune response on and off; regulation

Question 20

describe the cascade induction attribute of cytokines

Answer 20

the action of one cytokine on a target cells causes the target cell to produce one or more additioal cytokines; keeps immune response going or shuts it off; more regulation

Question 21

what are the 6 major cytokine families?

Answer 21

1. IL-1 family
2. Class I (Hematopoeitin) family
3. Class 2 (Interferon) family
4. Tumor Necrosis Factor family
5. IL-17 family
6. Chemokines

Question 22

what is the IL-1 family of cytokines secreted by?

Answer 22

dendritic cells and macrophages

Question 23

what are the 2 functions of the IL-1 cytokine famiky?

Answer 23

1. proinflammatory

2. systemic effects

Question 24

describe the proinflammatory function of IL-1 cytokine family

Answer 24

promotes inflammation by increasing permeability of capillary walls at site of infection to allow leukocytes to migrate to site of infection

Question 25

give an example of the systemic effects function of IL-1 cytokines (hint: what do they serve as?)

Answer 25

IL-1 cytokines are pyrogens, so they are responsible for fever; they work in an endcorine manner for this, traveling through the bloodstream to the brain to tell it to increase body temp

Question 26

what was the first family of cytokines discovered?

Answer 26

Class I (Hmeatopoeitin) family

Question 27

what are the Class I (Hematopoeitin) family of cytokines secreted by?

Answer 27

a diversse set of cells

Question 28

what are the 2(ish) functions of the Class I (Hematopoeitin) family of cytokines?

Answer 28

1. Hematopoeitic 2. diverse functions: like stimulation of T cell proliferation and stimulation of differentiation of B cells into plasma cells

Question 29

what is hematopoeisis?

Answer 29

formation of blood cells

Question 30

what are the 3 types of Class 2 (Interferon) cytokines?

Answer 30

1. Type I: IFNA and IFNB 2. Type II: IFN gamma 3. Type III: IFN lambda

Question 31

what are Type I IFNs (from the Class 2 IFN family) secreted by?

Answer 31

dendritic cells and macrophages

Question 32

what is the function of Type I IFNs (from Class 2 IFN family)?

Answer 32

prevent viraally infected cells from replicating

Question 33

what are Type II IFNs (from Class 2 IFN family) secreted by?

Answer 33

produced by T cells and NK cells

Question 34

what is the function of Type II IFNs (from Class 2 IFN family)?

Answer 34

induce macrophage activation so phagocytosis can occur more readily

Question 35

what are Type III IFNs (from Class 2 IFN family) secreted by?

Answer 35

dendritic cells

Question 36

what is the function of Type III IFNs (from Class 2 IFN family)?

Answer 36

upregulate expresion of genes that control viral replication

Question 37

what is the function that ALL IFNs perform?

Answer 37

increase expression of MHC complex proteins

Question 38

where is MHC I found?

Answer 38

on all nucleated cells

Question 39

where is MHC II found?

Answer 39

only on dendritic cells and macrophages

Question 40

what does the presence of MHC do to dendritic cell and macrophage classification?

Answer 40

classifies them as "professional antigen presenting cells" ooooooh

Question 41

how to TCRs relate to MHC complexes?

Answer 41

T cell receptors bind to antigen that is bound to the MHC complexes

Question 42

what kind of MHC do cytotoxic T cells recognize?

Answer 42

MHC I

Question 43

what kind of MHC do helper T cells recognize?

Answer 43

MHC II

Question 44

what does MHC I serve as for all cells?

Answer 44

serves as a way for ANY cell to mark itself as infected

Question 45

how do lymphocytes related to MHCs?

Answer 45

lymphocytes are constantly browsing all healthy cells, and MHCs serve as a traffic stop/breathalyzer to alert lymphocytes to a problem

Question 46

what are the 2 kinds of cytokines in the Tumor Necrosis Factor family? describe

Answer 46

1. soluble: secreted by cell | 2. membrane-bound: expressed on cell

Question 47

what are the 2 soluble TNF famoly cytokines?

Answer 47

1. TNF alpha | 2. TNF beta

Question 48

what is TNF alpha secreted by?

Answer 48

macrophages

Question 49

what is the function of TNF alpha?

Answer 49

proinflammatory

Question 50

what is TNF beta secreted by?

Answer 50

lymphocytes

Question 51

what is the function of TNF beta?

Answer 51

increases MHC expression (similar to IFNs)

Question 52

what is the function of membrane-bound TNF family cytokines?

Answer 52

regulate lymphocyte function

Question 53

list 5 membrane-bound TNF family cytokines

Answer 53

1. lymphotoxin-Beta 2. BAFF 3. APRIL 4. CD40L 5. FasL

Question 54

what is the most recently discovered cytokine family?

Answer 54

IL-17

Question 55

what are IL-17 cytokines produced by?

Answer 55

TH17 cells; a subset of helper T cells

Question 56

what is the function of IL-17 cytokines?

Answer 56

proinflammatory

Question 57

what is the function of the chemokine family of cytokines?

Answer 57

chemotaxis

Question 58

define chemotaxis

Answer 58

soluble factor-directed (chemokine) cell movement; attract cells to site of infection