Immunoglobulins 1 Flashcards
(20 cards)
Two types of blood proteins?
Albumins (full saturation with ammonium sulphate)
Globulins (half saturation with ammonium sulphate)
Blood is split into…
Plasma + serum
2 major functions of antibodies
1-binding foreign antibodies encountered by the host
2-mediating effector function to neutralise or eliminate foreign molecules
What IgE?
A class of immunoglobulin
Main reason for bonds?
Helps sustain structure
CDR?
Complementary determining region
2 different chains?
Heavy and light
Analysis of IgG?
Multiple myeloma
Rearrangement of gene process? For heavy chain expression
D segment joins to j segment- DJ segment joins a V segment
Encodes the variable (V) region heavy chain
Light chain expression?
V segment joins to a J segment- assembled VJ segment encodes the V region of the light chain
How many binding sites on antigens?
2
What’s an antigen?
A foreign macromolecule which can bind to antibodies, inducing an immune response
Antibodies can distinguish between in… (3 things)
1-primary structure of an antigen
2-secondary and tertiary structure of an antigen
3-isomeric forms of an antigen/epitope
What’s an epitope?
Portion of the antigen which binds to the antibody
Polyclonal antibodies?
each antibody can interact with different epitope a on the antigen
Monoclonal antibodies?
Can only bind to one epitope on the antigen
Evidence for 2 identical binding sites
- The ability of monoclonal antibodies to cross link
- effect of proteolytic degradation of IgG on cross linking
- Both H and L chains involved
Advantages of Fab fragments as tools
- smaller than whole IgG mol.
2. 2 fab regions can bind and precipitate
IgG structure?
2 heavy chains 2 light Maintained by disulphide bonds Constant and variable Each part important
Immunoglobulin definition?
Blood proteins which are involved in immunity
