Exam 2- Antibodies and the memory response

Question 1

antibodies are (definition)

Answer 1

secreted immunoglobin proteins

Question 2

secreted antibodies react with antigens where

Answer 2

extracellular spaces

Question 3

structure of antibodies

Answer 3

heterodimer with 2 light chains (22kda) and 2 heavy chains (55kda) joined by a disulfide bridge; variable ends are the first 110 a.a. of amino terminal (specificity)

Question 4

variable region of antibody

Answer 4

110 a.a. on amino-terminal of both chains

Question 5

VDJ

Answer 5

generates Ig diversity; makeup the variable region

Question 6

Part that determines the class of antibody

Answer 6

constant region-binds the immune cells (macrophages) and reacts with complements

Question 7

Antibody Function

Answer 7

circulate blood seaking target antigen, find, bind, and mark for destruction(5 ways)

Question 8

5 mechs of antibody function

Answer 8

Agglutination
Fixes and activates complement
Opsonization
Neutralization
Antibody dependent cell mediated cytotoxicity

Question 9

Agglutination

Answer 9

crosslink antigen to reduce number of infectious units (clump)-able b/c 2 binding sites

Question 10

Fixes and activates complement

Answer 10

activate complement via CLASSICAL pathway—–ab binds to antigen on pathogen and activates formation of C3 convertase to activate MAC and inflammation

Question 11

antibodies activate complement via

Answer 11

classical pathway

Question 12

Opsonization

Answer 12

coating antigen w/ antibody which enhances phagocytosis (IgG and C3B); Phagocytes have Fc receptor that binds IG (bound to antigen) causes phagocytosis

Question 13

Fc receptor binds to

Answer 13

IgG on opsonized antigen for phagocytosis; or to Ab in the case of antibody dep. cell mediated cytotoxicity

Question 14

Neutralization

Answer 14

blocks adhesion of bacteria and viruses to mucosa, blocks attachment of toxins (no longer can act on host cells)

Question 15

Antibody dependent cell mediated cytotoxicity

Answer 15

target cells for destruction by eosinophils and NK cells——Eosinophils have Fc receptor that binds Ab, recognizing antigen on large pathogens (worms)— secretes perforin and granzyme; NKs can recognize Ab on antigens too!

Question 16

target cells for destruction by eosinophils and NK cells

Answer 16

Antibody dependent cell mediated cytotoxicity

Question 17

Number of different heavy chain constant regions

Answer 17

5 ISOTYPES

Question 18

determines the Ig Class

Answer 18

the a.a. sequence in the constant region of the heavy chain

Question 19

IgM structure

Answer 19

monomeric; secreted is pentameric

Question 20

IgM function

Answer 20

expressed on B cells (BCR), Activates compliment, good at agglutination (can bind 10) and is first class produced in primary response

Question 21

1st class of antibody produced in primary response

Answer 21

IgM

Question 22

most abundant Ig in serum

Answer 22

IgG

Question 23

Antibody that crosses placenta

Answer 23

IgG-very small

Question 24

antibody involved in complement activation

Answer 24

IgG and IgM

Question 25

Predominant class of antibody in secreations

Answer 25

IgA

Question 26

Helps protect mucosal membranes/mucosal immunity

Answer 26

IgA

Question 27

Antibody which exists as a dimer

Answer 27

IgA (secretory)

Question 28

IgA

Answer 28

secreations, mucous membranes, J train across intestinal wall, dimer,

Question 29

Antibody that is membrane bound on B cells (BCR) and not very present in serum

Answer 29

IgD

Question 30

Very little present in serum

Answer 30

IgD

Question 31

IgE

Answer 31

allergic reactions and worm infections

Question 32

IgD

Answer 32

B cell membrane bound, little in serum

Question 33

antibody for allergic reactions and worms

Answer 33

IgE

Question 34

Class switching

Answer 34

increases number of functional antibodies without altering antigen specificity

Question 35

Class switching progression

Answer 35

IgM initilal (agglutination) --> IgG (default-good for activating complement and therefor MAC to attack infection

Question 36

IgM vs IgG

Answer 36

different classes, meaning different heavy chains, but same Fab region because they bind the SAME ANTIGEN

Question 37

determines antibody class

Answer 37

heavy chain

Question 38

determines antigen bound

Answer 38

Fab region

Question 39

mechanism of class switching

Answer 39

enzymes delete regions of the constant region--no loss of DNA --> IgM loss of DNA puts constant region first and --> IgG

Question 40

Memory response

Answer 40

a larger population of sensatized plasma cells are ready to respond (already a few cells developed)

Question 41

Memory B cells from primary response

Answer 41

differentiate into plasma cells w/o needing direct contact to the Th cell--NOTE antibodies made in secondary response are better

Question 42

Types of Memory B cells

Answer 42

1. Memory plasma cell-long lived plasma cell in BONE MARROW and secretes IgG (CLASS SWITCHED)--no T equivalent 2. Normal, central memory B cells-reside in secondary lymphoid organs and proliferate slow to maintain pool of memory B cells--primed army for next infection and can replenish memory plasma cells

Question 43

keeps B cell army available-reside in lymphoid organs

Answer 43

normal, central memory B cells

Question 44

secrete IgG-reside in bone marrow

Answer 44

B memory plasma cells

Question 45

Memory antibody characteristics

Answer 45

higher number and affinity in response, BCR also acquires mutations --> binds better

Question 46

immunization

Answer 46

exposure to antigen

Question 47

differentiate amt and rates of antibodies in primary and secondary responses

Answer 47

in 1: fast IgM; IgG comes later and both die fast in 2: fast IgM; IgG comes faster, stronger, longer

Question 48

effect of secondary exposure on IgM

Answer 48

NONE!! responds fast and dies fast still, IgG is just faster, stronger, and longer

Question 49

Cell mediated and humoral response on adaptive immunity

Answer 49

chosen branch is based on pathogen, humoral --> antibodies good at attacking extracellular

Question 50

branch good at producing antibodies that attack extracellular things well

Answer 50

humoral

Question 51

branch good at attacking intracellulars

Answer 51

cell mediated; producing helper T cells, activated macrophages and Cytotoxic T cells

Question 52

best at clearing intracellular bacteria

Answer 52

macrophages

Question 53

best at clearing viral infections

Answer 53

T cells

Question 54

Kill intracellular org

Answer 54

must transform, phagocytize and MHCII presentation, antibody and complement