Antibody Structure

Question 1

IgM

Answer 1

involved in neutralization and activation of the complement system, does not opsonize (can only do so with the help of complement), cannot do ADCC

does not have FcM receptors

Question 2

IgG

Answer 2

involved in neutralization, opsonization, activation of complement system, transport across placenta

intrachain disulfide bonds occur between same residues

Question 3

IgA

Answer 3

involved in neutralization, transport across epithelium (gut, urinary tract, mother’s breast milk)

predominant class in secretions

Question 4

IgE

Answer 4

cause of allergies, very show half life, very low serum level, associated with immune response to parasites

fixes to mast cells and triggers them to release histamine

Question 5

Fab

Answer 5

fragment that binds antigen

Question 6

Fc

Answer 6

fragment that is crystallized, binds to effector cells, neutrophil, macrophages, complement system

where effector cells bind, recognized by phagocytes, constant region, heavy chain, C-termini

Question 7

antibodies against adhesins

Answer 7

block colonization and uptake

Question 8

neutralizing antibody

Answer 8

blocks binding of toxin to cell-surface receptor

Question 9

hypervariable region

Answer 9

3 for each domain (12 total), determine specificity of binding, surrounded by 4 framework regions