Lecture 11 Antigen Presentation to T cells

Question 1

Antibodies recognize and bind _____ protein structures

Answer 1

intact (native) - visible on protein surface

Question 2

TCR bind a complex of _____ fragment and _______ on the cell surface

Answer 2

antigen; self-molecule

Question 3

The protein that _____ bind can be continuous or discontinuous

Answer 3

antibodies

Question 4

______ binds epitopes that are Linear and buried in the protein

Answer 4

TCR

Question 5

____ cells are virus specific

Answer 5

cytotoxic T cells

Question 6

some highly specialized cells do not have a lot of _____ because they do not renew

Answer 6

MHC I

Question 7

Cytotoxic T cell function

Answer 7

kill cells that present a viral protein on MHC I

Question 8

CD4 cells function

Answer 8

recognize MHC II on infected macrophages, TH1 activate macrophage to destroy bacteria inside

Question 9

Follicular helper T cell function

Answer 9

TFH cells recognize antigen on B cells and activate them to proliferate and differentiate into plasma cells

Question 10

Extracellular material is taken up by

Answer 10

phagocytosis or endocytosis

Question 11

______ surround components in cytosol and deliver them to lysosomes

Answer 11

autophagosomes

Question 12

Viruses are degraded in the _____ and loaded onto MHC I. The effect when presented to ___ cells is death.

Answer 12

cytosol; CD8+ T cells

Question 13

Bacteria can be taken up in ______ and their antigens are presented via MHC II. The effect when presented to _____ cells is to activate the macrophage to kill the bacteria.

Answer 13

endosomes; CD 4+

Question 14

Proteins can be delivered to a cell from extracellular pathogens via _____ in B cells. These can be presented on ____ to CD4+ cells to stimulate B cells to produce antibodies

Answer 14

endocytosis; MHC II

Question 15

Virus uses ____ to make proteins

Answer 15

cell machinery

Question 16

Viruses are synthesized in ______ and their peptide fragments are bound by MHC I in ____.

Answer 16

cytosol; ER

Question 17

proteins tagged by ubiquitin go through _____ to break up into peptides

Answer 17

proteasome

Question 18

proteasome has _______ core and 2 ____ regulatory caps

Answer 18

20S catalytic core; 19S

Question 18

The ______ recognizes polyubiquitin

Answer 18

19S regulatory cap

Question 19

______ cause covalent tagging of K48 linked polyubiquitin chains

Answer 19

E3 ligase

Question 20

peptides broken down by proteasome can go through ______ from cytosol to ER

Answer 20

TAP 1 and TAP 2 channel

Question 21

going through TAP channel is ________ dependent

Answer 21

energy

Question 22

partly folded MHC I alpha chain bind to _____ until beta2 microglobulin binds

Answer 22

calnexin

Question 23

When beta2m binds, calnexin is released and MHC I is _____ and binds to _______ (TAP associated)

Answer 23

partly folded; tapasin

Question 24

_____ (forms a heterodimer with tapasin) and _______ bind to MHC I

Answer 24

ERp57; calreticulin

Question 25

_____ can bind to MHC I and once proteins bind, folding is completed, MHC is released from _____ complex and exported to cell membrane

Answer 25

DRiPs (defective ribosomal products); TAP

Question 26

in early endosomes with bacterial antigens, there is _____ pH

Answer 26

neutral

Question 27

in the presence of proteins, there is a signal to _____ pH through _____ of H+

Answer 27

lower; influx

Question 28

The ______ of vesicles activates proteases to ________ antigens into peptide

Answer 28

acidification; degrade

Question 29

vesicles with peptides can fuse with vesicles containing ____

Answer 29

MHC II

Question 30

MHC II is made in the _____ and ____ is bound when its exported into vesicle to stabilize

Answer 30

ER; CLIP (part of invariant chain)

Question 31

____ binds to MHC II in ER

Answer 31

Invariant chain Ii

Question 32

Ii is cleaved after transport into ________ by noncysteine proteases to leave _____

Answer 32

acidified vesicle; LIP22

Question 33

LIP22 is cleaved by cysteine proteases to yield _____

Answer 33

LIP10

Question 34

_____ targets MHC II to the endosomal pathway

Answer 34

LIP10

Question 35

Cleavage of LIP10 yields _____ in the acidified vesicle (late endosomes)

Answer 35

CLIP

Question 36

_____ blocks pathogen peptides from binding to MHC II

Answer 36

CLIP

Question 37

____ binds to MHC II:CLIP complex, releasing CLIP

Answer 37

HLA-DM

Question 38

DCs can take up ____ bodies (virus infected cells) and is loaded onto MHC I to activate ____ to disengage and move around body

Answer 38

apoptotic; cytotoxic T Cells

Question 39

Cross-presentation/cross-priming

Answer 39

exogenous pathway for loading pathways onto MHC I