Immunodiagnosis Flashcards
Immunodiagnosis
using antibody to antigen interactions to ID pathogens and diagnose infections
serological test
in vitro diagnostic test of serum (in plasma; clotting factors removed; has antibodies)
Contains the antibodies
the Serum
How to do serological tests for antibodies
Combine serum with antigens –> clumping
Serological test for antigen in sample
isolate colonies and combine with known Ab –> clumps
Latex agglutination test
pathogen specific antibody cross links antigen coated latex –> complex that settles into clumps; the Abs blocks agglutination which would stack the latex tall
Hemagglutination Inhibition Test
Uses RBC as indicators instead of latex; use Ab to virus which blocks the viruses ability to agglutinate the RBCs (indicates presence of Ab)
Labeled antibody test
Use Ab that is linked to molecular label –> easily detect a visible change to detect antigen or Abs (ELISA, Western Blot, Fluorescence)
Immunoflourescence
Antigen attached to slide with patients serum –> Ab binds –> secondary Ab with flourescently labeled anti-Ig –> wash away unbound Ab
ELISA
Enzyme Linked Immunosorbent Assay
Enzyme Linked Immunosorbent Assay
Bind patient’s Ab to known antigen –> attach to 96 well plate –> use secondary Ab that is labeled with enzyme to detect patients Ab –> add substrate –> hydrolyzed by enzyme –> releases dye –> wells with color are positive for Ab –> double check this with a W blot
W Blot
Used to check ELISA; run gel electrophoresis to separate by size –> transfer to nitrocellulose membrane –> incubate membrane w/ primary antibody –> binds antigen –> add secondary antibody labeled with enzyme –> visualize prt
used to detect p24 HIV antigen
ELISA with W blot after
Immunochromatography test
used in many rapid tests; anti-antibodies on strip stop the movement of the Ab up the strip and is shown by color where density is
Used in many rapid tests
immunochromatography
