Activation Of Naive T Cells

Front 1

What are the ways that T cells enter the lymph nodes?

Back 1

1)HEV
2) afferent lymph

Front 2

What are the cytokines involved in rolling?

Back 2

L selecting
-you are selecting the cells you want

Front 3

When the T cell enters the the lymph node what cytokines are on it? What cytokines are on the lymph node?

Back 3

T Cell - LFA 1, L Selectin, chemokine receptor
HEV- GlyCAM-1, chemokine, CD34

Front 4

Which things interact?

Back 4

L selectin, CCR7 (chemokine receptor??)

Front 5

What is the molecule involved with activation?

Back 5

chemokines like CCL21

Front 6

What is the molecule involved with adhesion?

Back 6

integrins like LFA1

Front 7

What is the molecule involved with diapedesis?

Back 7

chemokines like CCL21 and CXL12

Front 8

What are the 5 steps of naive T cell entry into lymph node?

Back 8

1) T cell has LFA 1, selectin and chemokine receptor
2) lymph node as glyCAM 1, chemokine and CD 34
3) L-selectin bins GlyCAM1 to allow for rolling interaction
4) LFA 1 is activated by cehmokines binding to chemokine receptor on ECM
5) LFA 1 binds ICAM 1 tightly
6) Diapedesis occurs

Front 9

Once dendritic cells take up bacterial antigen where do they go?

Back 9

T cell areas

Front 10

What types of antigen are processed by MHC Class II?

Back 10

1) extracellular bacteria
2) soluble antigens
3) virus particules

Front 11

What types of antigens are processed by MHC class I?

Back 11

virus
cytoplasmic antigens

Front 12

What are the two ways you can get antigen to the MHC Class II?

Back 12

1) receptor mediated endocytosis
2) macropinocytosis

Front 13

What are the three ways you can get antigen to MHC Class I?

Back 13

1) viral infection
2) cross presentation after phagocytosis or micropinocytic uptake
3) transfer from incoming dendritic cell to resident dendritic cell

Front 14

What are ways that pathogen interacting with DC causes DC maturation and migration?

Back 14

1) immature dendritic cells are activated by PAMPS on pathogens which bind TLR
or DEC 205
2) TLR signaling induces CCR7 which helps pathogen processing
3) CCR7 directs migration to lymph noids
4) CCR7 directs expression of costimulatory molecules and MHC

Front 15

What is the signal of a mature dendritic cell?

Back 15

it has B7 on it

Front 16

What are the three types of APCs?

Back 16

1) dendritic cells
2) macrophage
3) b cell

Front 17

Where is each Professional APC located in lymph node?

Back 17

1) T cell areas - dendritic cells
2) everywhere - marcophages
3) follicles - B Cells

Front 18

Do all professional APCs express MHC?

Back 18

dendritic cells - onlymphoid tissue
macropahge - induced by bacteria and cytokines
3) lymphocyte - awlays

Front 19

Which of the professional APC has costimulator delivery?

Back 19

dendritic cells - constituitive
others - inducible

Front 20

Are the initial interactions between niave T cells and DC antigen specific or non specific?

Back 20

non specific

Front 21

What are the non specific interactions between T cells and DC?

Back 21

1) CD2-LFA
2) LFA-ICAM 1
3) LFA-1--> ICAM 2
4) ICAM 3- DC SIGN

Front 22

What are the steps of the non specific interactions?

Back 22

1) T cell binds dendritic cell through low affinity LFA -1: ICAM -1 interaction
2) binding of TCR and MHC sends signal to LFA-1
3) increased LFA-1 affinity

Front 23

Once activated what happens to T cells?

Back 23

they are trapped until they are activated
once activated they can leave

Front 24

What are the three signals APCS deliver to Naive T cells?

Back 24

1) MHC-TCR
2) B7.1 and B7.2 - CD 28 on T cell
3) cytokines from APC to cytokine receptor on T cell

Front 25

of the three signals APCs present to naive t cells what are their functions?

Back 25

1) MHC - activation
2) B7.1/B7.2 - survival
3) cytokines - differentiation

Front 26

What type of signal leads to T cell anergy?

Back 26

MHC without co stimulator

Front 27

What to T cells produce once htey are activated?

Back 27

Il-2

Front 28

What is function of IL-2?

Back 28

helps t cell enter cell cycle

Front 29

What are ITAMs?

Back 29

immunoreeptor tyrosin based activation motifs

Front 30

What is the purpose of ITAMs?

Back 30

activation of ZAP 70

Front 31

What is the signal pathway when a naive T cell is presented by an antigen by a dendritic cell?

Back 31

1) resting T cell
2) ITAMS unphosporylated
2) MHC binding phosphorylates ITAM
3) ZAP 70 binds ITAM
4) ITAM activated by LCK
5) ZAP 70 activates PLC gamma
6) PLC gamma cleaves PIP2 to DAG and IP3
7)downstream NKFB, NFAT and AP-1 change pattern of gene expression

Front 32

What is purpose of DAG in T cell activation cascade?

Back 32

1) activates protein kinase c theta
2) PKC theta activates NFKB
3) also activates RAS GRP--> activates MAP Kinase
4) Map KINASE activates Fos on AP1

Front 33

What is the purpose of IP3 in the cell activation cascade?

Back 33

1)IP3 increases intracellular Ca concentration activating calneurin phosphatase
2) Calnineurin activates NFAT

Front 34

What does cyclosporin do?

Back 34

supresses T cell activation by decreasing IP3 ability to increase Ca concentration and activate calnuerin

Front 35

What genes do NFAT, NFK-B, AP-1 and Oct -1 are transcription factors for?

Back 35

IL2 gene

Front 36

What is the difference in activated and naive T cells for the IL2 receptors?

Back 36

higher affinity binding
activated T cell only has the IL-2R B and gamma and not alpha chain
the alpha chain gives it high affinity for IL2

Front 37

What does rapamycin do?

Back 37

decreases ability of Il2 to signal the T cell for proliferation

Front 38

What are the two types of differentiated T cells?

Back 38

TH1
TH2

Front 39

What is the TH1 cell function? (4)

Back 39

-secretes IL2, IFN- gamma
-macrophage activation
-B cell activation
-opsonizing antibodies like IgG

Front 40

What is the TH2 cell function?

Back 40

-secretes IL4, IL5
-general activation of B cells to make antibodies

Front 41

maybe to remember between TH1 and TH2

Back 41

TH2 does not secrete IL2