Immunoglobulin Structure and Function

Question 1

what are antibodies aka

Answer 1

immunoglobulins

Question 2

where are immunoglobulins found

Answer 2

present in plasma, tissues, secretions and lymphatics

Question 3

what are immunoglobulins a product of

Answer 3

humoral immune system

Question 4

what are immunoglobulins secreted by

Answer 4

activated B cells - plasma cells

Question 5

what are the 5 classes of immunoglobulin

Answer 5

IgM
IgA
IgD
IgE

Question 6

what do immunoglobulins do

Answer 6

recognition function and trigger effector functions

Question 7

what is antibody structure

Answer 7

y shaped

2 identical heavy chains and 2 identical light chains

Question 8

what are the bonds between chins in antibody

Answer 8

disulphide bridges

Question 9

what are Fab and Fc regions

Answer 9

Fab - fragment antigen bindig regions 2 identical

Fc - fragment crystallising region

Question 10

what si the dual function go antibodies

Answer 10

recog function binding to antigen -Fab

effector function clearance mechanisms- interaction of Fc with effector molecules

Question 11

what are the two types of light chains

Answer 11

lambda and kappa

Question 12

what antibody classes use these light chains

Answer 12

all classes

Question 13

what are the light chains folded into

Answer 13

2 globular domains termed VL and CL

Question 14

what isVL and CL

Answer 14

VL - variable light domain at n terminus

CL - constant light domain at c terminus

Question 15

what does the heavy chain determine

Answer 15

antibody class

Question 16

what are the classes corresponding heavy chain

Answer 16

IgG - gamma
IgA - alpha 
IgM - knew
IgE - epsilon
IgD - omega

Question 17

what is the heavy chain folded into

Answer 17

4/5 constant globular domains 
VH
CH1
CH2
CH3
(CH4)

Question 18

what are antibodies essentially

Answer 18

glycoproteins

Question 19

if sugars are removed what does this do to the function

Answer 19

no longer functions

Question 20

what are the types of effector molecules

Answer 20

Fc receptors and complement

Question 21

how do antibodies recon millions antigens

Answer 21

3 hypervarible loops or CDRs in each V domain revealed by comparing sequences of diff antibodies

Question 22

what is CDR

Answer 22

complementarity determining region

Question 23

what do hypervaribale and CDRs form

Answer 23

antigen binding site

Question 24

what do CDRs form

Answer 24

close lying loops at one end of V domain

Question 25

what does the antigen binding site consist of

Answer 25

when 3 in Vh and 3 in Vl are paired their 6 CDRs create binding site

Question 26

what si the complementarity of antigen and bidding site

Answer 26

3d structures complementarity

Question 27

what are the allotropes of crabon

Answer 27

diamond graphite buckminsterfulleren

Question 28

what si the most abundant antibody in plasma

Answer 28

Ig (10mg/ml)

Question 29

what is the structure of IgG

Answer 29

y shaped 2HC 2LC 4 subclasses

Question 30

what is IgG efficient at doing

Answer 30

triggering complement and phagocytosis via Fc receptors

Question 31

what is IgG the only Ig to do

Answer 31

cross placenta from mother to foetus - protect baby

Question 32

what is the predominant antibody in secondary response

Answer 32

IgG

Question 33

where is IgM found

Answer 33

only in plasma and secretions | too large to go into tissues

Question 34

what is the structure f IgM

Answer 34

5 Y shaped units joined by J chain and disulphide bridges heavy chain has 5 globular domains

Question 35

how many binding sites on IgM for antigen

Answer 35

10 - good at agglutining viruses

Question 36

what is IgM efficient at

Answer 36

activating complement

Question 37

what is IgM predominant for

Answer 37

primary response

Question 38

when an infection hits what are the Ig present at primary nd secondary responses

Answer 38

primary - IgM | secondary - IgG

Question 39

what is human IgA used in

Answer 39

imp serum Ig (2-3mg/ml)

Question 40

what is the IgA major antibody in

Answer 40

``` saliva milk colostrum gut gent-urinary system ```

Question 41

what is th class of antibodies encountered first by many invading bacteria and viruses

Answer 41

IgA

Question 42

how many subclasses of IgA

Answer 42

2

Question 43

what are the forms IgA come in

Answer 43

monomeric (serum) and dimeric (secretory)

Question 44

how do the subclasses of IgA vary

Answer 44

IgA1 - O linked sugars and N linked IgA2- all n linked sugars

Question 45

what are the charateristsics of IgE

Answer 45

5 domains in each heavy chain is a monomer deco with loads n linked sugars

Question 46

what is IgE effector function

Answer 46

interacts with recep Fc(epsilon)RI | against parcatsic infection

Question 47

what is the receptor Fc(epsilon)RI

Answer 47

high affinity recep expressed on mast cells and basophils assc with allergic reactions

Question 48

what is serum conc of IgD like

Answer 48

very low

Question 49

where is IgD found

Answer 49

on surface of lymphocytes

Question 50

whats función IgD

Answer 50

unclear may be involved in control antibody response

Question 51

what do Fc receptors do

Answer 51

receptors bind sp to Fc region of immunoglobulins

Question 52

what si th other effector mol

Answer 52

complement

Question 53

do Fc receptors vary

Answer 53

present on many different immune cells macrophages neutrophils basophils and mast cells

Question 54

what can binding of antibody to FcR on immune cells cause

Answer 54

``` phagocytosis release activated oxygen sp and enzymes release inflam mediators enhance antigen presentation clear immune complexes ```

Question 55

what are mediators of allergic response

Answer 55

histamine prostaglandins leukotrienes