B-cell Development And Clinical Application Of Antibodies- Lecture 9/30/21

Question 1

V(D)J Recombination

Answer 1

The DNA rearrangement mechanism that creates many billions of BCRs and TCRs using few Ig and TCR genes

Question 2

RAG1 and RAG2

Answer 2

Two proteins that mediate V(D)G, expressed in developing B cells in bone marrow and Developing T cells in the thymus

Question 3

Generation of antibody diversity (4)

Answer 3

1. Germ line- Inherited genes
2. Combinatorial- V+D+J and H+L
3. Junctional- Imprecise joining and TdT
4. Somatic Hypermutation- point mutations in variable regions

Question 4

TdT

Answer 4

Terminal deoxyribonucleotidyl transferase, adds random nucleotides to junction of VDJ

Question 5

Class switching

Answer 5

As the antibody matures, it can switch Ig class with IgM coming first

Question 6

B-cell development

Answer 6

Stem cell-> Pre B cell (Heavy chain only)-> immature B cell (IgM) only-> mature B cell (Naive B cell)

Question 7

How B cells recognize self

Answer 7

If the B cell is exposed to antigen while only expressing IgM, it dies

Question 8

CD19 and CD20

Answer 8

Surface protein markers of a B cell

Question 9

Types of immunity (4)

Answer 9

• Natural Passive (Maternal IgG, IgA milk)
• Artificial passive (injection of pre formed Ig)
• Natural active (exposure to pathogen)
• Artificial active (Immunization)

Question 10

Rabies immunoglobulin (RIG)

Answer 10

Artificial Passive, Ig given to someone exposed to rabies, polyclonal antibodies