Lecture 2: Antibody Function

Question 1

Which of these use Fc receptors?
What Igs are involved?

• Ag-specific receptor (BCR)
• Agglutination
• Neutralization
• Complement activation
• Opsonization
• ADCC
• Mast cell activation

Answer 1

Opsonization - IgG
ADCC - IgG
Mast cell activation - IgE

Question 2

Which antibody isotype(s) are primary responsible for the following function?
Explain what this term means.

Ag-specific receptor (BCR)

Answer 2

Ag-specific receptor (BCR) - all isotypes

Question 3

Which antibody isotype(s) are primary responsible for the following function? Explain what this term means.

Agglutination

Answer 3

Agglutination - IgM

Question 4

Which antibody isotype(s) are primary responsible for the following function?

Neutralization

Answer 4

Neutralization - IgG and IgA

Question 5

Which antibody isotype(s) are primary responsible for the following function? Explain what this term means.

Complement activation

Answer 5

Complement activation - IgM and IgG

Question 6

Which antibody isotype(s) are primary responsible for the following function? Explain what this term means.

Opsonization

Answer 6

Opsonization - IgG

Question 7

Which antibody isotype(s) are primary responsible for the following function? Explain what this term means.

ADCC

Answer 7

ADCC - IgG

Question 8

Which antibody isotype(s) are primary responsible for the following function? Explain what this term means.
Mast cell activation

Answer 8

Mast cell activation - IgE

Question 9

In multiple myeloma, what cells are malignant? What results from this?

Answer 9

Multiple Myeloma - malignant plasma cells

• excessive production of mAb
• normal hematopoiesis is disrupted
• anemia, low WBC counts, infection

Question 10

What is the major serum protein?

Answer 10

albumin

Question 11

g-globulin is found in the __.
It is mostly composed of __.
It appears on a gel as a __.

Answer 11

g-globulin: in the serum
mostly composed of antibodies (immunoglobulins)
It appears on a gel as a smear. Lots of Ig types.

Question 12

What is a CDR? Where is it?
What does it do?
How many does a single Ab have?

Answer 12

CDR = Complementarity Determining Region (hypervariable region)
Where: at the end of the variable regions
Purpose: For Ag specificity
How many: 3 per H, 3 per L: 6 total

Question 13

Where are there disulfide bonds in Ab?

Answer 13

Disulfide bonds

• between heavy chains
• between heavy and light chains

Question 14

What does the Fab region do? What is it made of?

Answer 14

Fab: Ag binding region

1 L, 1 part of H

Question 15

What is the Fc region? What does it do?

Answer 15

The Fc region is the constant region

Activate complement, opsonization, etc