Cell mediated/ T cells

Question 1

During anitgen recognition and T cell activation:

When a T cell recognizes an antiG displayed, it will increase integrin_________ to help keep it locked in place with APC

Answer 1

LFA-1

Question 2

What two recognitions need to happen between the TCR and the APC for our first signal during AntG recognition and T cell activaiton

Answer 2

1. TCR recognizes MHC

2. TCR’s CD4 or CD8 needs to recognize and bind to MHC

Question 3

CD4 or CD8 recognize the MHC protein ______ of the andtiG presented

Answer 3

independent

Question 4

How many TCR co-receptors need to be engaged with the APC to active a naive T cell

Answer 4

2 or more

—thus T cell only responds if it encounters an array of MHC:antiG complexes

Question 5

Alpha/betta TCR recognize what kind of antiG

Gamma/delta TCR recognize what kind of antiG

Answer 5

peptides

lipids

Question 6

2 signals to activate a T cell

1st: TCR interacts with _____
2nd: T cell CD28 interacts with ______

Answer 6

MHC/antigen

B7

Question 7

Once Tcell has it’s 2 signals during activation of naive T lymphocytes, it releases this cytokine

Answer 7

IL-2

Question 8

IL-2 released during activation by T cell promotes

Answer 8

clonal expansion and proliferation and differentiation to effector cells

Question 9

A T cell TRC binds to MHC with antiG but the T cells’ CD28 has NO B7 to bind to from APC… what happens?

Answer 9

Anergy or tolerance by T cell

Question 10

CD28 on T cell will bind to ______ on APC along with TCR:MHC binding and the T cell will release this cytokine ____

Answer 10

CD28: B7

releases IL-2

Question 11

CD3 is a signaling receptor expressed on

Answer 11

all T cells

Question 12

When CTLA-4 on T regs bind to B7 what happends

Answer 12

negative regulation

Question 13

CTLA-4 binding to B7 induceds ITAM or ITIM

Answer 13

ITIM

Question 14

To anchor naive T cells during antiG presentation, LFA-1 on the Tcell anchors to ______ on the APC

Answer 14

ICAM

Question 15

bindting of LFA-1 on Tcells to ICAM on APC causes APC to release what? and why?

Answer 15

releases chemokines to the Tcell… the chemokines will tell the TCell to put the LFA-1 into high affnity statte and bind that ICAM super tight

Question 16

Once and APC engulfs an antiG it will:

1. upregulate expression of ____ on it’s cell surface
2. Will increase production of ______ to present antiG
3. Will release this cytokine _____

Answer 16

Co-stimulators (B7)
MHC production increases
IL-12

Question 17

A B cell can act as a _______ for a T cell

Answer 17

professional APC

Question 18

If a B cell is acting as a Professional APC, what does it do to the antiG that bind to it’s BCR on the cell surface?

Answer 18

will internalize it and process it to present at MHC II to a T cell

Question 19

This is a T cell proliferation cytokine T cells release to act on themselves

Answer 19

IL-2

Question 20

T cell proliferation by IL-2 occurs during what days?

Answer 20

day 1-2 after activation

Question 21

Daughter T cells of proliferating cells are ______ thus express identical TCR and co-recpetor (CD4 or CD8) and recognize same antigen as naive T cell

Answer 21

CLONES

Question 22

Which expands more, CD4+ or CD8+ T cells after activation and expansion

Answer 22

CD8+

Question 23

Once a T cell begins to secreate IL-2 (recogniztion of MHC and co-stim molecule happened), what does the T cell need to upregulate?

Answer 23

upregulates expression of IL-2-alpha chain for a high affinity IL-2 recetpors

Question 24

this is the high affinity part of the IL-2 receptors

Answer 24

IL-2alpha

Question 25

Why do T cells want to upregulate expression of IL-2 alpha receptor on cell surface?

Answer 25

creates high affnity binding for IL-2 and IL-2 is a proliferation signal for T cells... they have recieved all proper signals that their antiG is out there, now we want them to expand

Question 26

During differentiation, progeny of our original activated T cells become:

Answer 26

effector T cells or memory T cells

Question 27

How do T cells determine if they will be memory or effector cell?

Answer 27

they express dif genes driven by transcription factors

Question 28

Once T cell is activated to effector function in the _______ it migrates out to the ________

Answer 28

peripheral lymphoid | site of infection (via chemokine signal)

Question 29

CD4+ effector T cells respond to antiG by making surface molecules and cytokines... the function of these molecules and cytokines is to activate: ______ and _____

Answer 29

macrophages and B lymphocytes

Question 30

_____on CD4+T cells binding to _______ on APC provides amplification signal APC to maintain it's awesome immune resonspe

Answer 30

CD40L on CD4+ binding to CD40 on APC

Question 31

INF-gamma and IL-12 cause Tsubset to turn into:

Answer 31

Th1 cells

Question 32

Th1 cells release

Answer 32

INF-gamma

Question 33

INF-gamma released by TH1 cells has these three functions

Answer 33

- stimulates anitB production to bind APC Fc receptors - activates complment - stimulates co-stim expression

Question 34

This subset does phagocyte mediated killing of intracellular microbes

Answer 34

Th1

Question 35

IL-4 drives expression of this Th subset

Answer 35

Th2

Question 36

Th2 will release these cytokines

Answer 36

IL-4, IL-5 and IL-10

Question 37

this T sub functions to promote isotype switching and allergies

Answer 37

Th2

Question 38

TGF-B, IL6 and IL-23 promote this Thsub

Answer 38

Th17

Question 39

Th17 releaesse

Answer 39

IL-17

Question 40

this T sub does neutrophil inflmation, phagocyte killing of extracellular bacteria and fungi

Answer 40

Th17

Question 41

Memory T cells do not produce cytokines or infected cells BUT

Answer 41

maintain ability to do so once exposed to their antiG

Question 42

resolution of immune response occurs w/in ______ after eradication of infection

Answer 42

1-2 weeks

Question 43

Antigen from intracell microbes is recognized twice: 1. In peripheral lymphoid and we _______ require co stimulation 2. In site of infection and we ________ require co stim

Answer 43

DO require | DON"T require

Question 44

Once a CD4+ cell recognizes an APC presenting antiG in the periphery... how does it cause fight the infection?

Answer 44

it will release cytokines to cause inflammation or will send cytokine to tell APC (macrophage) to activate and kill the ingested microbe

Question 45

Once a CD8+ cell recognizes and infected cell with microbe in periphery it will

Answer 45

kill the infected cell

Question 46

Th1 will activate a macrophage to-->

Answer 46

kill intracellular bacteria

Question 47

Th2 will activate B cells to--->

Answer 47

secreate antiB to parasites or allergens

Question 48

Th17 will activate PMNs to ---->

Answer 48

kill bacteria and fungi involved in autoimmune resonse

Question 49

CD8+ can be activated by: Direct= Indirect =

Answer 49

``` direct = anitgien + APC Indirect = antigen + Th1 help ```

Question 50

Endothelial cells that have infection will increase expression of _____ and ____ as a function of innate immunity

Answer 50

TNF and IL-1

Question 51

Effector T cells ready to patrol the periphery for infection will decrease expression of ______ and increase expression of ______ to inhibit trafficking back to lymph node

Answer 51

L-selectin (lose this) | E and P selecting (will express this

Question 52

T cells that are activated will express high levels of LFA-1 and VLA-4, why?

Answer 52

helps with tight adhesion to endothelium at sight of infection

Question 53

This is a complex reaction of many parts of the innate immune system in vascularlized tissues and involves: - recruiting phagos and granulos to site of infection - initiated by change in blood vessels to promote leukocyte recruitement

Answer 53

Inflammation

Question 54

A phagocyte engults a macrophage in epithelium... the phagoctye releases ____ and _____ to change structure of epithelium to make is leaky

Answer 54

TNF and IL-1

Question 55

Inflammatory cells such as ____, _____ and _____ migrate through leaky epithelium to site of inflamation

Answer 55

monocytes, lymphocytes and neutrophils

Question 56

T cell homing is ________ of antiG recognition

Answer 56

INDEPENDENT ----all T cells recognize this chemokine signal sent by damaged tissue to maximize effectiveness of cell mediated immune response

Question 57

An effector T cell gets to sight of inflammation and reconiizes IT's own antiG... as a result the T cell will increase expression of:

Answer 57

VLA4 integrins so it can bind to VCAM1 on site of infection

Question 58

What is our chemokine receptor that homes T cells to the lymph nodes

Answer 58

CCR7 and L-selectin

Question 59

What is our chemokine receptor that homes T cells to teh periphery?

Answer 59

CXCR10 or e/p selecting

Question 60

If a T cells is expressing CCR7 and L selecting we know it's located in

Answer 60

lymph node

Question 61

if a T cell is expressinc CXCR10 or E/P selectin we know it's in the:

Answer 61

periphery or tissues

Question 62

CD4+ can work with macrophages that are APC's by: | CD4+ can work with B cells presenting antiG by:

Answer 62

- activating the macrophage to kill phagocytized microbe | - activate APC B cell to secreate antiB with enhanced abilities to neutralize and eliminate anitGs

Question 63

INF-gamma released by Th1 on APC B cells will cause B cells to

Answer 63

go complement binding and opsoinizing via IgG antibodies

Question 64

what is a macrophage's response to Th1 that releases IFN-gamma

Answer 64

- produce reactive oxygen species, NO, lyososomal enz - will secreate TNF, IL1 and IL-12 - increase expression of MHC and co-stimulators

Question 65

What is the special feedback loop between macrophages and Th1?

Answer 65

Th1 releases IFN-gamma to macrophages.... ....macrophages get activated + release IL-12 as a response---- the IL-12 causes more Thsub to turn into Th1 and over/over/ove

Question 66

TH2 cells releasing IL-4 causes

Answer 66

B cell to isotype switch to IgG (antiB production) or release IgE for mast cell degranulation

Question 67

Th2 releasing IL-5 causes

Answer 67

eosinophil activation against helminths

Question 68

Th2 releaing IL-4 with IL-13 can promote a macrophage

Answer 68

to undergo ALTERNATE macrophage acitvation so more about tissue repair and fibrosis)

Question 69

this subset pushes macrophages to be activated while this Th subset pushes for inactivation of macrphages

Answer 69

Th1==activation | Th2 for inactiation

Question 70

IL-17 released from Th17 will cause:

Answer 70

inflammation and neutorphil release

Question 71

this Th will increase recruitment of PMNs and maintain epithelial barrier integrity

Answer 71

Th17

Question 72

How do CTL's kill?

Answer 72

they secreate proteins that create pores in infected cell membrane :perforins and GranZ and express FasL that incduces apoptosis

Question 73

CTL's express this ligand that can induce apoptosis

Answer 73

Fas Ligand | binds to Fas receptor on target cells

Question 74

Activated CTL's make _____ to drive it's own proliferation and differentiation

Answer 74

IL-2

Question 75

If a CTL recognizes an APC that has a weak co-stimulatory signal.... who can help it out so that it can still this APC

Answer 75

CD4+ will release IFN-gamma that will bind to the APC and cause the APC to express more co=stimulatory signals to the CTL can kill it

Question 76

These guys x-link many different clones of T cells with MHC II class expressing APCs

Answer 76

superantiG

Question 77

IL-1 and TNF are responsible for

Answer 77

acute phase protein release from liver and changes vascular permeability

Question 78

IL2 causes

Answer 78

T cell proliefation

Question 79

Because the super antiG binds outside of recognition cleft to many different TCR's we get what kind of expansion

Answer 79

NON-clonal expansion

Question 80

End resultiof superantiG is this:

Answer 80

cytokine storm