Lecture 46

Question 1

What is clonal expansion ?

Answer 1

• Expansion of specific plasma and memory B cells

- selective expansion of unique B cells that interact with antigen

Question 2

What do plasma cells do?

Answer 2

Secrete antibodies

Question 3

How are plasma cells formed?

Answer 3

B cells are activated by T helper cells and binding of native antigen, B cells then differentiate into plasma & memory B cells

Question 4

How are plasma cells formed?

Answer 4

B cells are activated by T helper cells and binding of native antigen, B cells then differentiate into plasma & memory B cells

Question 5

What are the main antibodies expressed on Naive B cells>

Answer 5

IgM is secreted as a pentamer

IgD monomer

Question 6

What do memory B cells do?

Answer 6

• persist for years in blood and lymphatic tissue

- respond rapidly to antigen encounter and become plasma cells

Question 7

How do memory B cells differentiate into plasma cells?

Answer 7

• recognition of antigen by B cell receptor

- does not require T helper cell help

Question 8

What is a primary immune response?

Answer 8

SLOW - first encounter of pathogen

• takes 7-14 days before sufficient antibody is produced to eliminate pathogen
• low amounts of antibody - mainly IgM
• Memory B cells and Memory T cells are created

Question 9

What is the secondary immune response?

Answer 9

FAST - 2nd encounter of pathogen

• takes 2-3 days - sufficient antibody is produced to eliminate the pathogen
• memory B cells respond rapidly to antigen and become plasma cells which secrete antibodies
• IgG is produced
• principle behind vaccinations