Antigens and Antibodies Flashcards
Draw an antibody molecule and label the parts of the heavy chain, light chain, constant portion, variable portion, fab, fc, antigen binding site, hinge region, domains
It should look like this, if it does not try again
What types of bonds form between antigens and antibodies?
non-covalent
What are the non-covalent bonds that bind antibodies?
electrostatic forces, hydrogen bonds, Van der Waals forces, hydrophobic forces, Cation-pi interaction
What are the properties of antigen-antibody binding?
reversible and goes to equilibrium, pH dependent, ion strength deoendent, takes longern to bind at cooler temps
Using affinity chromatopgraphy, draw and explain the steps to purify a virus.
needs one column
Using affinity chromatopgraphy, draw and explain the steps to purify an IgG antibody.
insert picture - needs two columns
What is an antigen?
a molecule that binds to an antibody or a TCR
What are the charactersistics of a good antigen?
the best antigens would be a large foreign pritein because that correlates to the amount of epitopes that can react to it
What is a hapten?
a small molecule that is an antigen
What can a hapten bind to?
a b cell or t cell recptor - not immunogenic
What happens when a hapten binds to a transport protein?
it becomes a large foreign protein
What is an example of a hapten?
poison ivy
When can an antibody be an antigen?
when the antibody from one species is injected into antoher species
What is an anti-immunoglobulin?
an antibody to an antibody
What makes up the antigen binding site of an Ig molecule?
the hypervariable regions of the variable heavy and variable light domains
What shapes can the antigen binding site be?
pocket, groove, and extended surface
What is antibody affinity?
the sum of the attractive forces minus the repulsive forces; i.e the sum of all of the covalent bonds
What is a linear epitope?
the antibody binds to the parts of the antigen (AA) that are adjacent to each other
What is a conformational epitope?
Parts of the antigen are brought together by folding, therefore it needs remain folded in order for the antibody to bind
What are the five classes of antibodies?
IgG, IgM, IgE, IgA, and IgD
What antibody is the first made in an immune response?
IgM
What is the structure of IgM?
it is a large pentamer held together by a j-chain
Is the half life of IgM long or short?
short
Where is IgM located?
mostly in vasculature
What are the functions of IgM?
complement fixation, agglutinating bacteria, opsinizing
What class of antibodies is the highest in plasma?
IgG
What is the structure of IgG?
monomer
What is the half life of IgG?
3 weeks
What are the functions of IgG?
neutralization, agglutination, block the entry of bacteria to receptor, mediate ADCC, and fix complement; also important for neonates
Which antibody classes do not fix complement?
IgA, IgE, and IgD
Which antibody class do we make the most of every day?
IgA
What is the structure of IgA?
dimer held together by a j-chain
What is IgA secreted from?
plasma cells
How many binding sites does IgA have?
4
What is the function of IgA?
neutralizaiton, blocking the entry of bacteria or neutralizing viruses
Where is IgA located?
on mucosal surfaces
Where is IgE located?
on mast cells
What is the function of IgE?
sensitizes mast cells, aids in allergy response and defense against parasites
What is IgD important for?
it is an important marker of maturation in B cells
List 6 ways antibody can function in protection from disease.
agglutination, neutralize toxins, block attachment, complement fixation, opsonization, antibody-dependent-cell-mediated cytotoxicity
Of the 6 ways that an antibody can function in protection from disease, which way utulizes the Fc binding site?
complement fixation, opsonization, and antibody-dependent-cell-mediated cytotoxicity
Of the 6 ways that an antibody can function in protection from disease, which way utilizes the antigen binding site?
agglutination, neutralize toxins, and block attachment
What antibody classes are involved in agglutination?
IgM and IgG
What antibody classes are involved in neutralization?
IgG, IgM, and IgA
What antibody classes are involved in blocking?
IgA an IgG
What antibody classes are involved in opsinizing?
IgM and IgG
What antibody classes are involved in complement fixation?
IgG and IgM
What antibody classes are involved in Adcc?
IgG
What antibody classes are involved in sensitization of mast cells?
IgE
