T-Cell Receptors and MHC Complex - Diebel Flashcards Preview

IHO Week 3 > T-Cell Receptors and MHC Complex - Diebel > Flashcards

Flashcards in T-Cell Receptors and MHC Complex - Diebel Deck (55)
1

What do T-Cells require in order to be activated?

Cell-to-cell contact with antigen presenting molecules on the surface of other cells

2

Th1 CD4+ T-Cells are polarized by:

IL-12
IL-18
IFN-gamma

3

Th1 CD4+ T-Cells effector cytokines produced:

IGN-gamma (pro-inflammatory & chemotactic for monocytes/macrophages)
TNF

4

What types of cell-surface molecules/receptors do APC have?

PRR = Pathogen Recognition Receptor (PAMPs)
CD80 (B7-1) binds to T-cell CD28
CD86 (B7-2) binds to T-cell CD28
MHC II

5

What types of cell-surface molecules/receptors do T-cells have?

CD28 binds to CD80/86
CD4 binds to MHCII
CD3/TCR binds to MHC II

6

What master transcription factor generates cytokines in Th1 T-cells?

T-Bet

7

How are M1 (angry) macrophages activated and what cytokines do they secrete?

Activated by IFN-gamma secreting Th1 T-cells

TNF-alpha and IL-1

8

Th17 CD4+ T-Cells are polarized by:

TGF-Beta
IL-1
IL-6
IL-23

9

Th17 CD4+ T-Cells effector cytokines produced:

IL-17
IL-22

10

What master transcription factor generates cytokines in Th17 T-cells?

ROR-gamma-t

11

What is the main function of Th17 T-cells?

Cause Inflammation; more powerful that Th1; cause severe autoimmunity through IL-17

12

What is the main function of Th1 T-cells?

Recognize antigen and make lymphokines to attract M1 macrophages to attack a serious infection

13

Where do Th17 T-cells play their biggest role?

Maintaining the integrity of mucosal surfaces

14

Th2 CD4+ T-Cells are polarized by:

IL-4

15

Th2 CD4+ T-Cells effector cytokines produced:

IL-4
IL-5
IL-13

16

What master transcription factor generates cytokines in Th2 T-cells?

GATA3

17

What is the main function of Th2 T-cells?

Alternatively Activates M2 Macrophages to wall-off parasites/pathogens and promote healing; IL-4 attracts eosinophils

18

Follicular Helper Tfh CD4+ T-Cells are polarized by:

IL-6
IL-21

19

Follicular Helper Tfh CD4+ T-Cells effector cytokines produced:

IL-4
IL-21

20

What master transcription factor generates cytokines in follicular helper Tfh T-cells?

Bcl-6

21

What is the main function of the follicular helper Tfh T-cells?

Stimulated by antigen to migrate from T-cell areas of lymph nodes into the B-cell follicles, where B-cells are activated and undergo class switching

22

Treg CD4+ T-Cells are polarized by:

IL-2
TGF-Beta

23

Treg CD4+ T-Cells effector cytokines produced:

IL-10
TGF-Beta

24

What master transcription factor generates cytokines in Treg T-cells?

FOXP3

25

What is the main function of the Treg T-cells?

Suppress activation and function of all other T-cells; known as antihelpers

26

Describe IPEX.

Regulatory T-cells are not working properly to turn off the immune response

27

How is the kiss of death or lethal hit initiated y Cytotoxic Killer CD8+ T-cells?

Through the Fas (CD95) - Fas (CD95L) ligand interaction, the target cell has been given the signal to undergo apoptosis through DNA fragmentation and nuclear collapse.

28

How are Cytotoxic T-Cells activated?

Contact in the lymph node with antigen-presenting dendritic cell and IL-2 from Th1 T-cells

29

What markers on the cell surface of B-cells are used to fluorescently identify them?

CD19
CD20

30

What markers on the cell surface of T-cells are used to fluorescently identify them?

CD3
CD4
CD8

31

How are T-cells restricted?

Only recognize specific antigen on cells that are genetically identical to themselves (MHC)

32

What do APC Dendritic Cells express?

High levels MHCII
B7 (co-stimulatory molecule)

33

How must APC macrophages be activated?

Phagocytosis to express MHCII
Co-stimulatory molecules

34

What do B-cells express and how must they be activated?

MHC II
Antigen binding to antibody prior to co-stimulatory molecules

35

How are TCR activated for signal transduction?

CD3 and DC cytokines

36

LFA-1 (leukocyte functional antigen)

ICAM-1 (intercellular adhesion molecule

37

CD2 bind to?

LFA-3

38

Somatic Mutation in T-Cells

Addition of 0-6 nucleotides by TdT can be added between the V-D or D-J domains

39

How are T-cells selected?

1) Cannot recognize "self"
2) Not recognize free antigen
3) Recognize antigen peptide plus self MHC

40

What is positive selection of T-cells?

T-cells must recognize MHC Class I or MHC Class II molecules (self-restriction)

41

What is negative selection of T-cells?

T-cells that recognize self-antigens bound to MHC II are killed (T-cells need to be tolerant to self-antigens)

42

What cytokines can be released by CD8+ T-cells?

TNF, Perforin, and Granzymes

43

What are the three "classical" MHC Class I gene loci?

HLA-A
HLA-B
HLA-C

44

MHC Class I Structure

1 transmembrane domain
3 alpha domains
1 B2 Microglobulin (cell surface)

45

What are the MHC II gene loci that encode 2 peptides (alpha subunit and beta subunit)?

DP encodes DP aB
DQ encodes DQ aB
DR encodes DR aB

46

What does MHC III produce?

Complement Proteins
TNF-alpha and TNF-Beta
Lymphotoxin Beta

47

HLA-B27

Ankylosing spondylitis
Psoriasis
IBD
Reiter's Syndrome

48

HLA-DR2

Narcolepsy
MS
Hay Fever
Lupus

49

HLA-A3/B14

Hemochromatosis

50

HLA-DQ2/GQ8

Celiac Disease

51

HLA-DR3

DM Type 1
Grave's Disease

52

HLA-DR4

DM Type 1
RA

53

HLA-B53

Malarial Resistance

54

How many different Class I MHC molecules could each cell express?

6

55

How many different Class II MHC molecules could each cell express?

12 (DP, DQ, DR)