Question | Answer |
antigen and antibody= | clumping |
What is indirect or passive agglutination? | Antigen affixed ot absorbed to the particle surface (particles are coated with antigens not normally found on their surfaces) |
What is hemagglutination? | use of RBC's; not the antigen of rbc's themselves but the passively attached antigens that are bound by antibody. |
What are some of the inert particles? | latex, charcoal, clay, glass, gold, |
What happenes in both direct and indirect agglutination? | the biological fluid is tested for the presence of antibodies that will bind to the antigen |
What is direct or active agglutination? | The antigen is an intrinsic component of particle. Antigens found naturally on a particle. |
What is reverse agglutination? | the biologicalfluid is tested for the presence of antigen, and so the antibody is a component of the particle |
What is reverse passive agglutination? | Antibody is attached to the carrier particle instead of the antigen. |
coagglutination( direct bacterial agglutination) | Binding of specfic antibodies to surface antigens of bacteria causes bacteria to clump in visible aggregates. |
Quality of results depends on: | A:time of incubation,B:relative concentration of antibody or antigen, C:avidity of antigen conjugated to carrier, D:conditions of test environment( temp,pH & protein concentration) |
What is sensitization? | first stage is physical attachment of antibody molecules to antigens |
What is the zeta potential? | It is the potential around the rbc created by the negative charges of the sialic acid int he membrane of the cells. |
what is lattice formation? | the 2nd stage; cross-links between sensitized paricles & antibodies resulting in aggregation (much slower process than sensitization phase) |
Graded agglutination reactions | gently resuspend cell button and grade agglutination from 0(neg) to 4+, 2. hemolysis, 3.rouleaux formation-pseudoagglutination that can disperse by adding a few drops of saline. |