Antibody Structure Flashcards
What happens when you treat an antibody with papain which reduces some disulfide bonds?
The antibody breaks into three fragments: 2 identical Fab and 1 Fc
What happens whn you treat an antibody with a strong reducing agent that brakes all interchain disulfide bonds?
2 identical light chains
2 identical heavy chains
What is the function of the carbohydrate within the Fc?
Allows the antibody to interact with complement system
How are domains connected within an antibody?
Intrachain S—S bonds
What makes up the light chain?
1 variable region
1 constant region
What makes up the heavy chain?
1 variable region
3-4 constant regions
What are the give classes of antibodies?
IgG IgM IgD IgE IgA
What chains make up the IgG antibody?
2 light chains
2 gamma chains
What chains make up the IgD antibody?
2 light chains
2 delta chains
*Extra-long hinge region
What chains make up the IgE antibody?
2 light chains
2 epsilon chains
*An extra constant domain
What chains make up the IgM antibody?
2 light chains
2 mu chains
*extra constant domain
*J chain
What chains make up the IgA antibody?
2 light chains
2 alpha chains
*joined by a J chain
*Secretory component
What are the two types of constant chains in the light chain?
Kappa or Lambda
Where is the variable domain, C-terminus or N-terminus?
N-terminus
What is the complementarity-determining region, CDR?
The place where the antibody binds the antigen
How many subclasses or isotypes are there?
10
What are subclasses or isotypes?
Small differences in the amino acid sequences of their H chain C regions
What are allotypes?
Minor allelic differences in the sequence of immunglobulins between individuals
Inherited in the Mendelian fashion
What are idiotypes?
antibodies with unique combinding regions Slightly different CDR
What are the three most abundant antibodies in the serum? In descending order
IgG
IgA
IgM
The Fc can be bound by two things what are they?
- Phagocytic cells- PMN, eosinophils, Macrophages
2. C1q- need two adjacent IgG or only one IgM
