Blood typing Flashcards
soluble antigen + soluble antibody
insoluble complexes
visible aggregation of particles caused by combination of particulate antigen with specific antibody
Agglutination
where does the reaction of agglutination take place
on the surface of particle
antigen is adsorbed onto the surface of the particle
free floating
involves combining soluble antigen with soluble antibody to produce insoluble complexes that are visible
Precipitation
substance where antigens are coated/located
particles
Types of particles used in agglutination
RIBS
- RBC
- Inert carriers (ex.latex particles)
- Bacteria Cells
- Synthetic beads
Agglutination Reaction Steps
- sensitization
2. Lattice formation
Enhance Lattice formation
- Decrease the buffer’s ionic strength
- Add 5-30% albumin
- Increase viscosity of RBC
the secondary stage where the antibody and multivalent antigen forms a stable network
Lattice formation
exists a net-like configuration, which consists of a stable network between sensitized antigen and antibody. It takes much time to occur than the sensitization.
lattice
How can you decrease a buffer’s ionic strength
Use Low ionic strength saline/solution
Advantages of adding 5-30% albumin in ehancement of lattice formation
- neutralizes the surface charge of RBC
- allow RBCS to approach each other more closely
How can you increase viscosity of RBC
- Dextran or Polyethylene glycol ( PEG )
- Addition of enzymes (bromelin, trypsin, papain, ficin)
- Agitation & centrifugation
- Altering the pH & temp (igG and agM are antibodies of interest)
Immunoglobulin that agglutinates best at 4 degrees celsius and 27 degrees celsius
IgM
warm reacting antibody
IgG
cold reacting antibody
Ig M
IgG reacts best at what temperature
30-37 degrees celsius
Optimal ph for Agglutination
6.5-7.5
exceptions for altering ph and temp
acid loving antibodies (antibodies that react best at lower pH) , Anti M (MNS group) and anti P1 (P1 group)
Types of agglutination
CRAP , D
- Direct agglutination
- Passive agglutination (indirect agglutination)
- Reverse passive agglutination
- Agglutination inhibition
- Coagglutination
– specific antibodies that produce agglutination reactions
agglutinins
Involves antigen-antibody combination through single antigenic determinant on
the surface of the particle (1 Fab site and 1 epitope)
Sensitization
It follows the law of mass action: free reactants are in equilibrium with bound
reactants
Sensitization