Immunology 2

Question 1

Antibodies composed of?

Answer 1

2 heavy chains, 2 lights chains. Variable region near N terminus, Constant region at C terminus. Light and heavy chains connect via interchain disulfide bonds. Both Heavy chains are connected via interchain disulfide bonds. Each antibody has 2 binding spots!

Question 2

Light Chain

Answer 2

1 variable domain, 1 constant domain

Question 3

Heavy Chain

Answer 3

1 Variable domain, several constant domains. The constant regions of heavy chain interact with other components of the immune system to provide effector functions.

Question 4

Hypervariable Region

Answer 4

Each variable region has 3 hyper variable regions which come together to form the binding site!

Question 5

5 Classes of Antibodies

Answer 5

IgM - First antibody to be made (M for Monster, it’s big!)
IgG - Can do class switch from M to start making G
IgE - Used in Allergies (usually bound to surface of mast cells)
IgA - Antibody secreted.. in gut, breastmilk
IgD - On surface of B cells!

Question 6

Primary VS Secondary Response

Answer 6

Primary Response: See Antigen for first time, High IgM and low IgG levels.
Secondary Response: Body remembers antigen, High IgG and almost no IgM levels (Anamnestic)

Question 7

Affinity vs Avidity

Answer 7

Affinity - Strength of single determinant’s interaction with single antibody combining site.
Avidity = Antibody with multiple binding sites binds to a multivalent antigen… cause the attachment (avidity) to be much greater!

Question 8

3 Types of Antigenic Determinants

Answer 8

1. Conformational Determinant
2. Linear Determinant
3. Neoantigenic Determinant (by proteolysis)

Question 9

Sizes of Antigen-Antibody Complexes based off antigen concentration…

Answer 9

Small unless in zone of equivalence.. in which case will have LARGE complexes.

Question 10

What determines the class of antibody?

Answer 10

The CONSTANT region.