Day 16 - 08/10/14

Question 0

What is ANTI-SERUM?

Answer 0

SERUM which contains ANTIBODIES against MORE than one ANTIGEN.

Question 1

Where can ANTIBODIES be found?

Answer 1

Serum

Body Fluids

Question 2

What is an ANTIGEN?

Answer 2

Any MOLECULE that can be BOUND by an ANTIBODY.

Foreign/Self

Question 3

What is Burnet’s Clonal Selection Theory?

Answer 3

1) Each B-Cell has DIFFERENT Antigen Receptor (BCR)
2) Antigen BINDS to cognate BCR

3) Activation results in cell DIVISION and DIFFERENTIATION
4) The plasma cells (Antibody Factories) SECRETE antibodies that of the same SPECIFICITY

Question 4

What are the two types of light chains within an antibody structure?

Answer 4

Kappa (k)

Lambda (~)

Question 5

What are EPITOPES?

Answer 5

The REGION of antibody BINDING that can be LINEAR or CONFORMATIONAL.

There can be MANY EPITOPES per ANTIGEN.

Question 6

Give the 4 Biological Effects of Antibodies.

Answer 6

1) Protection from infectious disease
2) immobilisation - flagella of MOTILE bacteria
3) cytolysis - complement fixation
4) opsonisation - phagocytosis via Fc Receptors

Question 7

Give 4 shapes, antigen binding sites can take

Answer 7

1) Pocket
2) Groove
3) Shallow Surface
4) Protrusion

Question 8

What are the 5 Ig Classes?

Answer 8

IgM
IgD
IgG
IgE
IgA

Question 9

What is the POCKET binding site’s corresponding ANTIGEN?

Answer 9

Hapten (Ferrocene)

Question 10

What is the GROOVE binding site’s corresponding ANTIGEN?

Answer 10

HIV PEPTIDE

Question 11

What is the SHALLOW SURFACE binding site’s corresponding ANTIGEN?

Answer 11

HEL

Question 12

What is the PROTRUSION binding site’s corresponding ANTIGEN?

Answer 12

HIV gp120

Question 13

What’s the Structure of IgM?

Answer 13

1) μ heavy chain constant 
region
2)Expressed on naive B 
cells
3)Secreted as a pentameric 
molecule
4)1° immune response

Half Life: 10 days

Question 14

What is the Structure of IgD?

Answer 14

1) δ heavy chain constant 
region
2) membrane bound
3) trace in serum
4) long hinge region

Half Life: 3 days

Question 15

What is the Structure of IgG?

Answer 15

1) γ heavy chain constant
region

2) Human IgG1, 2, 3, 4

Half Life: 21, 20, 7, 21 days

Question 16

What is the Structure of IgA?

Answer 16

1)α heavy chain constant 
region
2) IgA1 & 2
3) Serum mainly monomers, 
external secretions - 
dimers and tetramers

Half Life: 6 days

Question 17

What is the Structure of IgE?

Answer 17

1) trace in serum
2) increased in atopies
3) extra Cε4 domain

Half Life: 2 days

Question 18

What is the Function of IgM?

Answer 18

1) Antigen binding - toxin and virus
neutralisation

2) Agglutination
3) Fc complement activation
4) Fc phagocytosis/opsonisation

5) does not cross placenta via
FcRn

Question 19

What is the Function of IgD?

Answer 19

1) co-receptor on B cells

2) secreted in upper respiratory track for
defence against respiratory pathogens

3) binds to basophils

4) induces:
anti-microbial factors (LL37, β-defensin 3)
pro-inflammatory cytokines (TNFα, IL-1β)
Chemotaxtic factors (IL-8, CXCL10)
ANTIBODY-inducing factors (IL-4, BAFF)

Question 20

What is the Function of IgG?

Answer 20

1) Ag binding - toxin and
virus neutralisation

2) Agglutination

3) Fc complement
activation

4) Fc phagocytosis/
opsonisation

5) cross placenta via
FcRn

Question 21

What is the Function of IgA?

Answer 21

1) protection at external
surface

2) Oral transition to
infant

3) agglutination

Question 22

What is the Function of IgE?

Answer 22

1) interact with FcεR on
mast cells

2) addition of Ag =
allergic response

3) Expulsion of parasites
at mucosal surface via
inflammatory response
- eosinophils

Question 23

Define Isotypes

Answer 23

light or heavy chain class

Question 24

Define Idiotypes

Answer 24

combination of specific VH and V