Antibodies

Question 1

what are the 5 isotypes of antibodies?

Answer 1

MAGED

Question 2

tell me about IgG

Answer 2

most abundant in the body, and usually secreted as a part of the secondary response as IgM undergoes isotype switching, can cross the placenta

half life is ~23d

function: opsonization, activate complement, helps with cytotoxicity to directly kill via NK cells, and can neutralize toxins/virus (IVIg)

Question 3

tell me about IgM

Answer 3

primary response antibody, large pentamer

half life is 5d

function: activates complement

Question 4

tell me about IgE

Answer 4

function: allergies, parasites, anaphylaxis

half life: 2d, bound to mast cells ~2wks

Question 5

tell me about IgA

Answer 5

first-line defense vs mucosal infections

half life: 5d

In mucosa → gut, mouth, nose, breast milk

Question 6

tell me about IgD

Answer 6

function unknown
biomarker on mature B cells

Question 7

explain function why isotype switching is important

Answer 7

changes the type of isotype to better tailor the immune response to the pathogen

start at IgM ➔ IgG ➔ most infections

Question 8

explain why somatic hypermutation is important

Answer 8

changes the antigen binding site via point mutations to help increase affinity to the antigen for a better immune response