Lecture 26

Question 1

Definition of an antigen?

Answer 1

anything that gets recognized by BCR/TCR immunogen AND triggers an immune response

Question 2

Definition of an immunogen

Answer 2

Something that triggers an immune response

Question 3

What is the criteria for something to be an antigen and an immunogen?

Answer 3

• foreignness
• molecular size
• chemical nature
• nucleic acid

Question 4

What is something that is an antigen, but NOT an immunogen called? What is an example of this?

Answer 4

a hapten; DNP

Question 5

Why is penicillin considered reactive?

Answer 5

because of the b-lactam ring– reacts with amino groups on host proteins

Question 6

What happens when someone is allergic to penicillin?

Answer 6

• penicillin binds and couples to B cell epitope, and Th cells costimulate B cell to produce IgE
• IgE binds to Fc receptors on mast cells
• cross-linking of IgE with penicillin protein activates mast cell’s histamine and inflammatory response

Question 7

What is the function of adjuvants in a vaccine?

Answer 7

induce cytokines, formation fo depot, promotion of transportation to drain lymph nodes