Serology Flashcards
Factors influencing antigen-antibody reactions
Specificity
Bonding
Concentrarion of antigen and antibody
Temperature
Time
pH
Surface charge (potentiators)
Red cell antigen-antibody reactions: A few isolated aggregates; mostly free-floating cells; supernatant appears red
Mixed field
Red cell antigen-antibody reactions: TINY agglutinates, turbid/red background or supernatant
Weakly positive
Red cell antigen-antibody reactions: SMALL agglutinates, 25% agglutination
1+
Red cell antigen-antibody reactions: MEDIUM agglutinates, 50% agglutination
2+
Red cell antigen-antibody reactions: LARGE agglutinates, 75% agglutination
3+
Red cell antigen-antibody reactions: One solid agglutinate, 100% agglutination
4+
Antigens are naturally found on the SURFACE of the particle
Direct agglutination
Antigens are naturally found on the RED CELL
Hemagglutination
Antigen is attached to the CARRIER particle
Passive agglutination
ANTIBODY is attached to the CARRIER particle
Reverse passive agglutination
Example of reverse passive agglutination
CRP determination
Uses BACTERIA as inert particles to which antibodies attached
Coagglutination
Lack of agglutination is a positive reaction
Agglutination-inhibition
Antibody is incorporated into the gel medium; antigen is placed on the well; precipitation is measured
Radial immunodiffusion (RID)
Mancini / Endpoint method. How many hours
IgG = 24 hours
IgM = 50-72 hours
Fahey and Mckelvey / Kinetic method. How many hours
18 hours
In kinetic method of RID, “d” means
Log antigen concentration
Antibody is incorporated into the gel medium; antigen is applied on the medium; formation of precipitin band
Oudin single diffusion
Ouchterlony double diffusion: Smooth curve line
Serological identity
Ouchterlony double diffusion: Spur formation
Partial identity
Ouchterlony double diffusion: 2 crossed line
Non-identity
Radial immunodiffusion + electrophoresis = rocket band is formed
Laurell rocket immunoelectrophoresis
Steps in PCR
Denaturation
Annealing
Extension
PCR step wherein double stranded DNA is separated
Denaturation
PCR step wherein primers anneal to target DNA
Annealing
PCR step wherein new strands of DNA is synthesized
Extension
Anti-nuclear antibody with PERIPHERAL / RING / RIM fluorescent pattern
Anti-dsDNA
Disease associated with anti-dsDNA
SLE