Test 1: lecture 6 T cell part 1

Question 1

what does T cell receptor look like?

Answer 1

Question 2

two classes of T cell receptors

Answer 2

alpha, beta

gamma, delta

Question 3

alpha beta T cell

Answer 3

Their TCR is composed of an a and a b chain. These are very similar in all mammals, birds and fish. It is the a and b chains that determine the specificity of a T cell.

most known type of T cell

Question 4

gamma delta T cell

Answer 4

•These differ in antigen recognition and function in different species.

–Often more abundant in tissues than circulation (in mice and humans)

–Share properties with innate cells (e.g. NK cells)

–Recognition of antigens differs from ab T cell

–Higher frequencies in blood of ruminants, pigs, poultry

Question 5

how to diversify TCR

Answer 5

multiple V genes in germ line

random recombination

junctional and insertional variability

Question 6

TCR complex are required for __

Answer 6

signaling

to get TCR to the surface of the cell

Question 7

____ are a complex of proteins that help TCR signal and get to surface of T cell

Answer 7

CD3

Question 8

___ heterodimer of the highly variable a and b chains (or g and d chains) expressed at the cell surface as a complex with the invariant CD3 chains.

Answer 8

Disulfide-linked

Question 9

mature alphabeta T cells express ___ or ___

Answer 9

CD4 or CD8

Question 10

___ molecules bind to MHC gene products expressed on antigen presenting cells

Answer 10

CD4 CD8

Question 11

___ enhance T cell-antigen presenting cell interaction and help with cell signal transduction

Answer 11

CD4 and CD8

Question 12

CD8 binds to

Answer 12

aplha 3 domain of MHC 1

Question 13

CD4 binds to ___

Answer 13

beta 2 domain of MHC class 2

Question 14

CD8 binds to the ___ of the MHC ___

Answer 14

alpha 3

class 1

Question 15

CD4 binds the ___ domain of MHC class ___

Answer 15

beta 2

MHC class 2

Question 16

MHC class 1 is made of what domains

Answer 16

alpha 1,2,3

Beta 2 microglobulin

alpha 3 binds to CD8

Question 17

MHC class 2 is made of domain ___

Answer 17

alpha 1,2

beta 1,2

B2 binds to CD4

Question 18

what does MHC stand for

Answer 18

major histocompatibility complex

(class 1 or class2 seen by T cells)

Question 19

•Genes encoding Class I and Class II molecules are encoded in ___

Answer 19

the MHC.

Question 20

what can T cells see

Answer 20

cell surface peptides of antigens presented by cells that express MHC antigens

Question 21

Antigen recognition by T cells requires ___ and presenting cells that express MHC molecules

Answer 21

peptide antigens

Question 22

there are a ___ number of genes that encode for MHC

Answer 22

limited (small amount)

Question 23

___ = many genes

Answer 23

polygenic

Question 24

___ = many shapes

Answer 24

polymorphic

Question 25

–Variation at the single genetic locus and its product within a species; the individual variants at that locus are called ___

Answer 25

alleles

Question 26

•Many alleles means that an individual is likely to be ___ at these loci

Answer 26

heterozygous

Question 27

•Both alleles are expressed in the cell- termed ___ expression.

Answer 27

codominant

Question 28

Answer 28

class 1 MHC

Question 29

Answer 29

class II MHC

Question 30

which MHC can see peptides longer then 10 amino acids?

Answer 30

class II

class I shape is limited to 9 amino acids or smaller

Question 31

Peptides bound to a particular type of MHC class I molecule have conserved patterns of ___

Answer 31

amino acids

Question 32

A common sequence in a peptide antigen that binds to an MHC molecule is called a ___

Answer 32

motif

Question 33

Amino acids common to many peptides tether the peptide to structural features of the MHC molecule. These are called ___

Answer 33

anchor residues

Question 34

Tethering amino acids need not be identical but must be ___

Y & F are aromatic

V, L & I are hydrophobic

Answer 34

related

Question 35

Side chains of anchor residues bind into ___ in the MHC molecule

Answer 35

pockets

Question 36

Different types of MHC molecule bind peptides with different ___ of conserved amino acids

Answer 36

patterns

Question 37

what class of MHC has anchor residues that are not localised at the N and C termini

Answer 37

class II

peptide can be any length due to shape of MHC class II

Question 38

how can MHC bind to so many different types of peptides?

Answer 38

• Use a small number of anchor residues to tether the peptide this allows different sequences between anchors and different lengths of peptide

Question 39

T cells can only be activated by interaction between the antigen receptor and peptide antigen in an ___ molecule

Answer 39

MHC

Question 40

Without T cells there can be no effective ___ response

Answer 40

immune

Question 41

The MHC has evolved two strategies to prevent evasion by pathogens

Answer 41

More than one type of MHC molecule in each individual

Extensive differences in MHC molecules between individuals

Question 42

___ :Several MHC class I and class II genes encoding different types of MHC molecule with a range of peptide-binding specificities.

Answer 42

polygenism

Question 43

Variation >1% at a single genetic locus in a population of individuals

Answer 43

POLYMORPHISM

Question 44

___ genes are the most polymorphic genes known

Answer 44

MHC

POLYMORPHISM

Variation >1% at a single genetic locus in a population of individuals

Question 45

The type and variant MHC molecules ___ in the lifetime of the individual

Answer 45

do not vary

Question 46

The diversity in MHC molecules exists at the ___ level

This sharply contrasts with the diversity in T and B cell antigen receptors which exists within the individual

Answer 46

population

you have the same MHC your whole life, where the types of T and B cells change depending what you are exposed to