2.4

Question 1

how are T cells in lymphoid organs alerted when there is an infection

Answer 1

APC are captured and processed and the antigens are transported to T cells

Question 2

antigens are transported from ___ to ___ where recognition by __ occurs

Answer 2

• tissue / mucosa
• lymphoid organs
• T cells

Question 3

what resides in tissues and captures microbes and antigens

Answer 3

dendritic cells

Question 4

___ are drained via lymphatic vessels or enter blood stream

Answer 4

cell-free antigens

Question 5

the majority of DC in tissues and lymphoid organs are ___

Answer 5

classical DC

Question 6

classical DC are in the ___

Answer 6

t cell zone of lymph nodes

Question 7

___ capture and process protein antigens

Answer 7

immature dendritic cells

Question 8

DC are activated via ___ and migrate to lymph nodes via ___

Answer 8

• PRR
• chemokine gradient

Question 9

chemokine gradient is produced by the upregulation of ___ and ___

Answer 9

• chemokine receptors (CCR7)
• costimulatory molecules

Question 10

___ present protein antigens to T cells

Answer 10

mature DC

Question 11

what determine the specific recognition of antigens by T cells

Answer 11

major histocompatability complex (MHC) molecules

Question 12

MHC molecules display ___ derived from ___

Answer 12

• peptides
• protein antigens

Question 13

___ on T cells recognize ____ displayed by ___ on APC

Answer 13

• T cell receptors
• peptide antigens
• MHC molecules

Question 14

what are human MHC proteins called

Answer 14

human leukocyte antigens (HLA)

Question 15

what are the 2 sets of highly polymorphic genes

Answer 15

• Class I MHC genes
• Class II MHC genes

Question 16

___ & ___ are susceptibility factors for periodontitis

Answer 16

• HLA-A9
• HLA-B15

Question 17

what is the structure of MHC class I molecules

Answer 17

• membrane proteins containing a peptide-binding cleft at the amino-terminal
• alpha chain associated with beta 2 - microglobulin with a groove accomodating 8-9 aa peptide

Question 18

what is the structure of MHC class II molecules

Answer 18

• membrane proteins containing a peptide-binding cleft at the amino terminal
• alpha & beta chains with a groove accomodating 10-30 aa peptide

Question 19

CD8 T cells only recognize peptides presented by ___

Answer 19

MHC class I

Question 20

how are peptides recognized by CD8 Tcells

Answer 20

the alpha 3 binds CD8 on CD8 Tcells

Question 21

CD4 T cells only recognize peptides presented by ___

Answer 21

MHC class II

Question 22

how are peptides recognized by CD4 T cells

Answer 22

beta 2 binds CD4 on CD4 T cells

Question 23

what do MHC polymorphisms ensure

Answer 23

that a population can deal with microbe diversity

Question 24

what are MHC class II expressed on & induced by

Answer 24

• APC
• IFN gamma

Question 25

what are MHC class I expressed on

Answer 25

all nucleated cells

Question 26

MHC molecules only bind ___

Answer 26

peptides derived from protein antigens

Question 27

T/F one APC can display multiple peptides

Answer 27

true

Question 28

how are proteins converted into peptides?

Answer 28

antigen processing pathways

Question 29

what are the 3 steps of extracellular protein processing

Answer 29

1 - antigen internalization
2 - antigen degradation in lysosome
3 - antigen (peptide) association with Class II molecules in endosome

Question 30

extracellular proteins are processed in ___ & peptides are displayed on ___ to ___

Answer 30

• endosome / lysosome
• MHC class II
• CD4 cells

Question 31

cytosolic proteins are processed by ___ & peptides are displayed on ___ to ___

Answer 31

• proteasome & endoplasmic reticulum
• MHC class I
• CD8 cells

Question 32

what are the 3 steps of cytosolic protein processing

Answer 32

1 - antigen degradation by proteasome
2 - peptide transport via TAP in ER
3 - antigen (peptide) association with class I molecules

Question 33

what is the significance of MHC-associated antigen presentation

Answer 33

optimization of response to different microbes in different locations

Question 34

extracellular microbes are associated with __

Answer 34

CD4 T cells

Question 35

intracellular microbes are associated with ___

Answer 35

CD8 T cells

Question 36

MHC molecules only bind ___

Answer 36

protein antigens

Question 37

MHC I molecules are composed of ___ & ___ and bind to __

Answer 37

• alpha chain
• beta-microglobulin
• CD8

Question 38

MHC II molecules are composed of ___ & ___ and bind to

Answer 38

• alpha chain
• beta chain
• CD4

Question 39

how are extracellular proteins processed for presentation to T cells?

a - processed in the endosome/lysosome and loaded onto MHC class II for presentation to CD4 T cells
b - processed in the endoplasmic reticulum and loaded onto MHC class II for presentation to CD8 T cells
c - processed in the endoplasmic reticulum and loaded onto MHC class I for presentation to CD4 T cells
d - processed in the endosome and loaded onto MHC class II for presentation to CD8 T cells

Answer 39

a - processed in the endosome/lysosome and loaded onto MHC class II for presentation to CD4 T cells

Question 40

what statement concerning antigen processing and presentation is correct?

a - class II molecules are composed of one beta2-microglobulin and one alpha chain
b - CD8 T cells recognize peptides associated with MHC class II
c - MHC locus consists of two sets of non-polymorphic genes
d - peptides bind outside of the cleft of MHC class I & II molecules
e - CD8 T cells recognize peptides associated with MHC class I

Answer 40

e - CD8 T cells recognize peptides associated with MHC class I

Question 41

what statement below reflects accurately antigen presentation to T cells?

a - neutrophils present antigen bound to TLR to T cells
b - B cells present antigen bound to BCR to T cells
c - macrophages present antigen bound to scavenging receptor to T cells
d - DC present antigen bound to MHC molecules to T cells
e - DC present antigen bound to microglobulin to T cells

Answer 41

d - DC present antigen bound to MHC molecules to T cells