Lecture 6

Question 1

define monoclonal antibody

Answer 1

lab-made protein that mimics the immune system by binding to a specific target (viral or cancer cell)

Question 2

what is omab mouse Mab

Answer 2

a fully mouse Ab

Question 3

what is ximab chimeric Mab

Answer 3

Ab human constant region and mouse variable regions

Question 4

what is zumab humanized Mab?

Answer 4

human Ab except for mouse hypervariable region

Question 5

what is umab humanized Mab?

Answer 5

fully human antibody

Question 6

umab monoclonal Ab have ________ ________

Answer 6

minimum immunogenicity

Question 7

germline configuration translates to:

Answer 7

before recombination

Question 8

germline DNA undergoes ________ ________

Answer 8

somatic recombination

Question 9

somatic recombination results in ___ ______ ____

Answer 9

DJ joined DNA

Question 10

DJ joined DNA undergoes somatic recombination as well and results in ___-______ ________ ___

Answer 10

VDJ-joined rearranged DNA

Question 11

define recombination signal sequences (RSS)

Answer 11

unique sequences flanking germ-line V, D, and J segments

Question 12

the conserved heptamer sequence is:

Answer 12

5’CACAGTG3’

Question 13

the conserved nonamer sequence is:

Answer 13

5’ACAAAAACC3’

Question 14

what are the combinations of bp’s that will flank a V, D, and/or J segment

Answer 14

7,23,9 or 7,12,9

Question 15

a gene segment flanked by and RSS with and ____ spacer can only be joined to one a gene segment flanked by a ____ spacer RSS

Answer 15

12bp; 23bp

Question 16

where does VDJ recombination occur?

Answer 16

ONLY in the lymphocytes

Question 17

What do RAG enzymes do?

Answer 17

they cause somatic recombination resulting in a signal joint and a coding joint

Question 18

signal joints are ____ _______ whereas coding joints are ______

Answer 18

very precise; random

Question 19

what results from the RAG enzymes cleaving the heptamer RSS?

Answer 19

DNA hairpins

Question 20

what is the role of TdT in junctional diversity?

Answer 20

adds N-nucleotides that correct overhang and increase diversity

Question 21

after N-nucleotides are added and gaps are filled, what is formed?

Answer 21

a coding joint

Question 22

what is a disadvantage of TdT and the coding joint?

Answer 22

autoimmunity

Question 23

which immunoglobulins are expressed on an immature B cell that has just entered the blood?

Answer 23

IgM and IgD

Question 24

coexpression of IgD and IgM is regulated by ___ __________

Answer 24

RNA processing

Question 25

membrane-bound immunoglobulins are associated with ___ and ___

Answer 25

Igα and Igβ

Question 26

what is a unique/important component of Igα and Igβ?

Answer 26

longer transmembrane domains

Question 27

what are the longer transmembrane domains on Igα and Igβ important for?

Answer 27

signal transduction

Question 28

where does somatic hypermutation occur?

Answer 28

germinal centers of the spleen and lymph node (periphery)

Question 29

what is the result of the nucleotide substitutions that occur from somatic hypermutation?

Answer 29

affinity maturation

Question 30

what is affinity maturation?

Answer 30

an increase in the affinity of Ab to bind to Ag

Question 31

What are the 4 ways that Ab diversity can be generated?

Answer 31

1. combinatorial diversity via VDJ recombination 2. junctional diversity via TdT enzyme 3. combinatorial association of light and heavy chains (μ+λ or μ+κ) 4. somatic hypermutation

Question 32

what is the first isotype that is secreted?

Answer 32

IgM

Question 33

IgM is secreted as a ________

Answer 33

pentamer

Question 34

IgM 's shape is ______ in blood and is in ______ conformation when attached to a pathogen

Answer 34

planar; staple

Question 35

when IgM binds to a J protein, what can then happen?

Answer 35

it can cross the epithelial linings to protect mucosal surfaces

Question 36

what does isotype switching involve?

Answer 36

recombination between switch regions

Question 37

what targets switch regions?

Answer 37

AID enzyme

Question 38

what does AID stand for?

Answer 38

activation induced deaminase

Question 39

AID enzyme is made only in _____________ cells

Answer 39

proliferating

Question 40

what 2 things is AID responsible for?

Answer 40

1. affinity maturation 2. isotype switching

Question 41

what are the functions of the Fc region?

Answer 41

receptor binding to activate mast cells, complement activation by binding Cq1, and regulating secretion by transporting Ab to the placenta and into the breastmilk

Question 42

what does IgG mainly function in?

Answer 42

neutralization, opsonization, diffusion

Question 43

what does IgM mainly function in?

Answer 43

activating the complement system

Question 44

what does IgD mainly function in?

Answer 44

sensitization of basophils (parasite infection control)

Question 45

what does IgA mainly function in?

Answer 45

neutralization and transportation across the epithelium to protect BALT and GALT

Question 46

what does IgE mainly function in?

Answer 46

sensitizing mast cells and basophils triggering an allergy response

Question 47

IgA is a _______

Answer 47

monomer

Question 48

IgG is highly ________

Answer 48

flexible

Question 49

which two changes in immunoglobulin genes are REVERSIBLE?

Answer 49

splicing and processing of RNA