8 – Innate Immunity V

Question 1

Cytokines are …

Answer 1

Small (25kD)
Heterogenous glycoproteins
Mostly soluble

Question 2

Cytokine production

Answer 2

= tightly regulated
Post-transcriptional/translational modifications

Question 3

Cytokine provides…

Answer 3

Provide cellular communication

Question 4

Cytokine affect behavior of (3)

Answer 4

Producing cell
Adjacent cells
Distant cells

Question 5

how does Producing cell work

Answer 5

-Autocrine mechanism
-Secrete cytokine bind to its own receptor

Question 6

how does Adjacent cells work

Answer 6

-Paracrine mechanism
-Cytokine secreted bind to nearby cells
-Directional release

Question 7

how does Distant cells work

Answer 7

-Endocrine mechanism
-Cytokine secreted and in circulation bind to receptor on far/distant cells

Question 8

pleiotropism:

Answer 8

1 cytokine may be produced by many different cell types & have effects on many different cell types

Question 9

redundancy

Answer 9

Different cytokines may have same effect

Question 10

Cytokine functions: (4)

Answer 10

Activation
proliferation (make copies)
differentiation (naive to effector)
survival/death of target cells

Question 11

cytokine activation & differentiation example:

Answer 11

Activate & differentiation B & T cells

Question 12

cytokine can change expression of

Answer 12

Change expression of adhesion molecules & chemokine receptors on target membranes

Question 13

cytokine can increase/decrease activity of…

Answer 13

Increase/decrease activity of particular enzymes – change transcriptional program
Modulate its effector functions
(TYPE I IFN)

Question 14

Cascade induction:

Answer 14

Action of one cytokine on one target cell induces that cell to produce one/more additional cytokines

Question 15

5 major groups of cytokines:

Answer 15

-IL – interleukins (1-37)
-IFN - interferons
(Type I – IFN-α/β
Type II – IFN- γ )
-TNF – tumor necrosis factors
(α/β)
-Hematopeoitin/growth factor
(GM-CSF, G-CSF )
-Chemokines
(migration of cells to site of infection)

Question 16

Cytokines can exert effect in different ways (4)

Answer 16

Pleiotropy
Redundancy
Synergy
Antagonism

Question 17

Pleiotropy

Answer 17

1 cytokine produces multiple effects

Question 18

Redundancy

Answer 18

More than 1 cytokine induce same effect

Question 19

Synergy

Answer 19

2 or more cytokines work together to induce an effect

Question 20

Antagonism

Answer 20

One cytokine can inactivate effect of another

Question 21

Specific cytokines are produced at…

Answer 21

different times in different locations

Question 22

Complex network of cytokines:
Same cytokine produced by

Answer 22

multiple cells

Question 23

Complex network of cytokines:
Each cell type can produce

Answer 23

multiple cytokines

Question 24

cytokines have a big influence on…

Answer 24

adaptive immune response

Question 25

Different cytokines can induce...

Answer 25

-differentiation of different cell types -Cytokines impact differentiation of T cells – signal 3 needed to activate it

Question 26

Different cell types produce...

Answer 26

-different cytokines produced by differentiated T cells

Question 27

what is 3rd signal to activate T cell?

Answer 27

Cytokines that can differentiate T cells

Question 28

what happens when 3rd signal is given to T cell?

Answer 28

1.once T cells differentiated = effector T cells 2. they secrete cytokines 3. the cytokines have a specific effect (they are different cytokines secreted depending on subset of T cells

Question 29

cytokines can determine...

Answer 29

type of adpative immune response we can get

Question 30

cytokines can influence who immuniy dominate more, what immunitites are we talking about?

Answer 30

Cell-mediated immunity Humoral immunity

Question 31

Cell-mediated immunity: Mostly directed to:

Answer 31

Viral infections Intracellular pathogens Some extracellular pathogens

Question 32

Cell-mediated immunity:Characterized by:

Answer 32

T helper cells --> innate immune cell activation Cytotoxic T lymphocyte (CTL) activation

Question 33

Humoral immunity Mostly directed to:

Answer 33

Extracellular bacteria/pathogens

Question 34

Humoral immunity Characterized by:

Answer 34

B cell activation Antibody production

Question 35

Proinflmmatory cytokine examples: (3)

Answer 35

IL-1β, TNF-α, IL-6

Question 36

TNF-α secreted by: mainly by

Answer 36

macrophages

Question 37

TNF-α stimulates:

Answer 37

-Migration of innate cells To site of infection -Dilate blood vessels Vasodilation help migration I-ncreases clotting (preventing pathogen from entering bloodstream)

Question 38

TNF-α involved in .... disease

Answer 38

Involved in autoimmune diseases

Question 39

Local TNF-α lead to

Answer 39

local inflammation -in tissues

Question 40

Systemic TNF-α lead to

Answer 40

systemic effects -in bloodstream -Sepsis: systemic infection & inflammation

Question 41

what is Acute phase response

Answer 41

A change in proteins present in blood that occurs during early phase of infection Induced by proinflammatory cytokines

Question 42

Acute phase response involves:

Answer 42

Increased synthesis/secretion of antimicrobial proteins from liver – acute phase proteins

Question 43

acute phase proteins

Answer 43

-MBL – mannose-binding lectin -Complement components -C-reactive protein – can opsonize bacteria & trigger classical complement cascade by binding to C1q

Question 44

Liver acute phase proteins help in... response

Answer 44

innate immune -help by opsonization or trigger compliment system

Question 45

Fever caused by IL-1β, TNF-α, IL-6 signals:

Answer 45

Signal to induce cascade leading to signal to hypothalamus --> increase body temperature

Question 46

IL-1β, TNF-α, IL-6 have effect on..

Answer 46

different tissues/cell types

Question 47

IL-1β, TNF-α, IL-6 can lead to...

Answer 47

-Acute-phase response -Mobilizing cells -Fever