IMIN Lec. 5

Question 1

Where do lymphocytes see APCs

Answer 1

lymph nodes

Question 2

Where do lymphocytes differentiate

Answer 2

Lymph nodes

Question 3

Where are APCs found and what do they do?

Answer 3

Activation of T cells, found in sites of microbial entry. They transport antigens to periphery where they can present antigens to T cells

Question 4

APCs present antigens on

Answer 4

MHC class one and two

Question 5

What does the MHC locus contain

Answer 5

two sets of polymorphic genes

Question 6

Polymorphism is

Answer 6

multiple alleles of a gene within a population

Question 7

How is peptide anchored

Answer 7

side chains bind into cleft.

additional residues are recognized by TCR in membrane

Question 8

MHC molecules have ____specificity

Answer 8

broad

Question 9

Any given MHC can present any peptide

Answer 9

with correct anchor residues

Question 10

Class II is presented to by

Answer 10

Professional APCs

Question 11

Class I presented to by

Answer 11

All nucleated cells

Question 12

Class I MHC has which chains?

Answer 12

alpha1 and alpha2->polymorphic residues are located in these domains, affecting peptide binding
alpha3 is invariant and contacts CD8

Question 13

Transport Associated with Antigen Presentation

Answer 13

drives transport of cytoplasmic proteins into ER

Question 14

Where does Class I associate with peptides?

Answer 14

in ER leumen

Question 15

what occurs if there is stable binding?

Answer 15

complex sent to cell surface via Golgi and exocytic vesicles

Question 16

Class II has which chains

Answer 16

alpha, noncovalently linked to beta

Question 17

Where does class II bind with microbes? Where does class I interact with intracellular microbes?

Answer 17

cell surface vs. cytoplasm

Question 18

Where do class I and II interact with peptides?

Answer 18

In ER; when endosomal vesicles can fuse with exocytic vesicles with MHC, and the invariant chain is removed

Question 19

CD4 T lymph stimulate

Answer 19

B lymph to make antibodies+phagocytes

Question 20

Properties of MHC

Answer 20

co-dominance and polymorphism

Question 21

Features of peptide binding to MHC

Answer 21

each T cell responds to a single peptide bound to MHC

• broad
• slow off rate
• stable exp. needs peptide for T cell recognition
• only restricted to peptides

Question 22

What provides 2nd signal for T lymph differentiation+T cell activation

Answer 22

costimulators and cytokines