EXAM 2 B Cells: Antibodies and Diversity

Question 1

B cells produce one unique ___

Answer 1

antibody

Question 2

B cells target one antigen ___

Answer 2

epitope

Question 3

B cells affect extracellular ___

Answer 3

pathogens

Question 4

B cells have ___ target diversity

Answer 4

infinite

Question 5

do B cells have high or low probability of reaching maturation?

Answer 5

low

Question 6

B cells undergo ___ and ___

Answer 6

clonal selection and expansion

Question 7

B cells improve targeting following ___

Answer 7

activation

Question 8

B cells can persist for ___

Answer 8

years

Question 9

what are the 6 phases, in order, of B cell infection response

Answer 9

1. repertoire assembly
2. negative selection
3. positive selection
4. searching for infection
5. finding infection
6. attacking infection

Question 10

small lymphocytes can produce ___ or ___

Answer 10

B cells (antibodies) or cytotoxic and helper T cells

Question 11

___ are fully differentiated forms of B cells that secrete antibodies

Answer 11

plasma cells

Question 12

describe the repertoire assembly phase of B cell infection response

Answer 12

generation of diverse and clonally expressed B-cell receptors in the bone marrow

Question 13

describe the negative selection phase of B cell infection response

Answer 13

alteration, elimination, or inactivation of B-cell receptors that bind to components of the human body

Question 14

describe the positive selection phase of B cell infection response

Answer 14

promotion of a fraction of immature B cells to become mature B cells in the secondary lymphoid tissues

Question 15

describe the searchign for infection phase of B cell infection response

Answer 15

recirculation of mature B cells between lymph, blood, and secondary lymphoid tissues

Question 16

describe the finding infection phase of B cell infection response

Answer 16

activation and cloncal expansion of B cells by pathogen-derived antigens in secondary lymphoid tissues

Question 17

describe the attacking infection phase of B cell infection response

Answer 17

differentiation to antibody-secreting plasma cells and memory B cells in secondary lymphoid tissue

Question 18

which phases of B cell infection response occur in the bone marrow, and which occur in seconary lymphoid tissues?

Answer 18

• phase 1, 2, and 3 occur in the bone marrow
• phase 4, 5, and 6 occur in secondary lymphoid tissues

Question 19

antibodies are also called ___

Answer 19

immunoglobulins

Question 20

antibodies are targeted ___

Answer 20

effector proteins

Question 21

antibodies are ___ specific

Answer 21

antigen epitope

Question 22

what are the effector functions of antibodies?

Answer 22

• receptors - B cells and granulocytes
• neutralization
• opsonization
• signaling

Question 23

are antibodies glycoproteins?

Answer 23

yes

Question 24

describe the theoretical and practical target diversity of antibodies

Answer 24

• theoretical: 1X10¹⁶
• practical: 1X10⁹

Question 25

what are the 3 sources of antiben diversity?

Answer 25

* genetic recombination * junctional diversity * somatic hypermutation

Question 26

antibodies have a ___ chain and a ___ chain

Answer 26

heavy and light

Question 27

describe the heavy chain of antibodies

Answer 27

* isotype determines antibody class * receptor interaction * proportionally small variable region * binds antigen

Question 28

describe the light chain of antibodies

Answer 28

* binds antigen * proportionally large variable region * two isotypes - κ - λ

Question 29

which isotypes dictate each antibody class?

Answer 29

- γ (IgG) - μ (IgM) - δ (IgD) - α (IgA) - ε (IgE)

Question 30

different ___ encode the heavy and light chains

Answer 30

genes

Question 31

cleavage of an antibody by a protease will result in the production of what?

Answer 31

* one Fc and two Fab fragments * cleaves at the disulfide bonds

Question 32

the light chains are at the ___ termini, and the heavy chains are at the ___ termini

Answer 32

* N only * C and N

Question 33

what are Fab regions?

Answer 33

antigen binding region (N termini)

Question 34

what is the Fc region?

Answer 34

conserved region (C termini)

Question 35

what is the difference between monomeric antibodies, dimeric antibodies, and pentameric antibodies?

Answer 35

* monomeric antibodies have the single antibody * dimeric antibodies are a complex of two antibodies + J chain (holds the two Abs together) * pentameric antibodies are a complex of five antibodies + J chain (holds all five Abs together)

Question 36

antibody functional diversity is determined by the ___ region of the antibody

Answer 36

conserved

Question 37

which antibody regions bind antigens?

Answer 37

variable regions

Question 38

what are hypervariable regions?

Answer 38

regions where mutations occur that really effect binding affinity of particular antibodies

Question 39

what are the 4 main antigen epitopes that antibodies target?

Answer 39

* terminal polysaccharide * polysaccharide chain * globular protein surface * globular protein pocket

Question 40

\_\_\_ is a molecule recognized by a B or T cell

Answer 40

antigen

Question 41

\_\_\_ is the region of an antigen bound by an antibody or MHC/TCR

Answer 41

epitope

Question 42

describe the 4 types of epitopes

Answer 42

Question 43

antibody structure facilitates \_\_\_

Answer 43

function

Question 44

\_\_\_ production coincides with B cell development

Answer 44

antibody

Question 45

gene rearrangement of antibodies occurs where?

Answer 45

the bone marrow

Question 46

somatic hypermutation and isotype switching occurs where?

Answer 46

secondary lymphoid organs and circulation

Question 47

antibody genes are assembled from \_\_\_

Answer 47

fragmented segments

Question 48

which chromosomes are the lambda light chain loci, kappa light chain loci, and heavy chain loci on?

Answer 48

* lambda light chain - chromosome 22 * kappa light chain - chromosome 2 * heavy chain - chromosome 14

Question 49

antibody production requries \_\_\_

Answer 49

recombination this produces enormous diversity of antigen binding

Question 50

what are the regions of genomes used to construct antibodies?

Answer 50

* kappa light chain * variable, joining/junctional, and constant/conserved * lambda light chain * variable, joining/junctional, and constant/conserved * heavy chain * variable, diversity, joining/junctional, and constant/conserved

Question 51

somatic recombination creates \_\_\_

Answer 51

antibody coding sequence

Question 52

somatic recombination follows a ___ sequence, tied to specific \_\_\_

Answer 52

* set * B cell developmental stages

Question 53

in somatic recombination, segments are ___ paired

Answer 53

randomly

Question 54

the ___ complex randomly pairs gene segments. the gene segments are randomly paired to create \_\_\_.

Answer 54

* RAG * coding sequences

Question 55

junctional diversity is created during \_\_\_

Answer 55

recombination

Question 56

every time you pair a variable, diversity, or junctional region, you add ___ to that sequence. which enzyme facilitates this?

Answer 56

* additional nucleotides * TdT - terminal deoxynucleotidyl transferase

Question 57

a single B cell can express all \_\_\_

Answer 57

antibody isotypes

Question 58

B cells usually only express one antibody, except in which case?

Question 59

somatic hypermutation rapidly increases \_\_\_

Answer 59

antibody affinity

Question 60

antibodies are important ___ and ___ tools

Answer 60

diagnostic and therapeutic

Question 61

what does polyclonal refer to?

Answer 61

multiple antibodies targeted against the same antigen

Question 62

what does monoclonal refer to?

Answer 62

a single antibody targeted against a single antigen

Question 63

describe how antibodies are important diagnostic and therapeutic tools

Answer 63

* diagnostic * pathogen identification * protein quantification * cellular identification * therapeutic * targeted killing * chemical delivery * immunomodulatory