Part 8: Serology Flashcards
What is serology?
The use of serum antibodies to detect and measure antigens, or conversely the use of antigens to detect serum antibodies
What is immunodiagnosis
Detection of antibodies (or antigens) can help provide definitive diagnosis
The amount of antibody in the blood is the
Titer
Note: as infection progresses more antibodies are formed and the amount of antibodies in the blood increases.
In terms of titer, what is characteristic of active infection?
A rise/increase in titer
What is serotype?
A strain that has a characteristic antigenic structure that differs from other strains
Serotype determination is critical for
Tracking transmission and emergence of infections
What serological testing uses two antibodies, one specific to antigen and one coupled to enzyme?
ELISA (Enzyme-Linked ImmunoSorbent Assay)
Note: If antibody antigen binding occurs, the enzyme on the second antibody reacts with substrate to create color change
The interaction between antibody and antigen results in cross-linking and lattice formation. What is this form of serological testing called?
Agglutination
The interaction between antibody and a soluble antigen in aqueous solution forms a lattice that develops into a visible precipitate. What is this form of serological testing called?
Precipitation
Immune precipitates can form not only in solution, but also in agar. As antibody and antigen diffuse toward one another, a visible line will form. What is this form of serological testing called?
Immunodiffusion
The oldest kind of serological testing is complement fixation whereby IF an antibody antigen complex is present, the antibody will
Bind complement and no lysis will occur.
The serological test whereby swelling of the capsule surrounding microorganism after reaction with an antibody is called
Capsular swelling
Note: basis for certain tests for identifying microorganisms
In serological testing, the test whereby specific antibodies (antitoxins) present will neutralize effect of toxin
Neutralization tests
Serological testing whereby fluorescent dyes can be attached to known specific antibodies which are then used to detect the presence of an antigen in serum
Immunofluorescence
Serological testing whereby movement of an antigen mixture in an agarose bell that allows the separation of different proteins along the gel based on size and charge
Immunoelectrophoresis