Antigens and Antibodies

Question 1

What is the shape and size of epitopes for T cells and B cells?

Answer 1

B Cells: either conformational or linear and 5-7 amino acids

T Cells: Linear and up to 20 amino acids

Question 2

Under what conditions are antibodies secreted?

Answer 2

When B cell is stimulated by a particular antigen, receives help from an activated T cell, and after differentiating into a plasma cell

Question 3

What is the basic structure of an immunoglobulin?

Answer 3

Two Heavy Chains: 3-4 globular constant domains, 1 variable domain, can be 1 of 5 classes
Two Light Chains: 1 V and 1 C domain, can either be kappa or lambda

Question 4

Ig digestion by papain and pepsin create what?

Answer 4

Papain => 2 F(ab) + 1 Fc

Pepsin => 1 F(ab)2 + 1 Fc

Question 5

Where in Ig is the variable domain found and what are the 2 regions of the variable domain?

Answer 5

Variable region is present in both heavy and light chains.

There is a variable hypervariable region and a less variable framework region

Question 6

How many genes are antibodies made from?

Answer 6

3 genes