labeled immunoassay

Question 1

demonstrated that antibodies could be labeled with molecules that fluoresce

Answer 1

(1941) Albert Coons

Question 2

Antibody that is conjugated with a fluorescent tag is added directly to unknown antigen that is fixed to a microscope slide

Answer 2

Direct Immunofluorescent Assays

Question 3

patient serum is incubated with a known antigen attached to a solid phase. Slide is then washed and an anti-human immunoglobulin containing a fluorescent tag is added

Answer 3

Indirect immunofluorescent assays

Question 4

homogeneous fluorescent immunoassay based on the change in polarization of fluorescent light emitted from a labeled molecule when it is bound by antibody

Answer 4

Fluorescence Polarization Immunoassay (FPIA)

Question 5

emits an increased amount of polarized light

Answer 5

labeled molecule is bound to antibody

Question 6

degree of polarized light reflects the amount of ______ that is bound

Answer 6

labeled analyte

Question 7

degree of fluorescence polarization is inversely proportional to ________

Answer 7

concentration of the analyte

Question 8

used to measure the amount of polarized light

Answer 8

Polarization analyzer

Question 9

emission of light caused by a chemical reaction, (oxidation reaction) producing an excited molecule that decays back to its original ground state

Answer 9

Chemiluminescence:

Question 10

Acridinium esters are oxidized by hydrogen peroxide which emit a quick ___ or _____ of light

Answer 10

burst or flash

Question 11

longer flash of light

Answer 11

luminol

Question 12

Detection system that is simple and relatively inexpensive

Answer 12

photomultiplier tubes

Question 13

uses electrochemical compounds that generate light when an oxidation-reduction reaction occurs

Answer 13

electrochemiluminescence immunoassay

Question 14

______ are often used as solid phase to capture the labeled antibody

Answer 14

Magnetic beads

Question 15

traditional procedure detects the presence of a specific antigen-antibody reaction by causing the in vitro activation of complement.

Answer 15

complement fixation

Question 16

If complement is not fixed, lysis of the ________ occurs

Answer 16

preantibody-coated reagent erythrocytes

Question 17

1906 first nontreponemal serological test for syphilis was developed by _________

Answer 17

August Paul von Wassermann

Question 18

This test used a crude liver extract from a fetus that was infected with syphilis as the source of the lipid antigen.

Answer 18

nontreponemal serological test for syphilis

Question 19

the Wasserman test was based on the principle of ________.

Answer 19

complement fixation

Question 20

patient serum was incubated with _______ in the presence of rabbit serum as the source of complement; this was followed by a detection system consisting of antibody-coated sheep red blood cells (RBCs). If the patient serum contained cardiolipin antibody, complexes were formed that bound the reagent complement and the indicator RBCs were not lysed.

Answer 20

cardiolipin antigen

Question 21

In contrast, if cardiolipin antibody was ______ in the patient serum, the reagent complement was free to react with the antibody-sensitized sheep RBCs to cause hemolysis

Answer 21

not present

Question 22

nontreponemal serological test for syphilis reaction results

Answer 22

+R: no hemolysis
-R: presence of hemolysis

Question 23

similar to complement fixation, but can be used only when the antibody being measured is directed against a hemolysin (bacterial toxin capable of directly lysing red blood cells)

Answer 23

Neutralization

Question 24

It is a diphtheria toxin-antitoxin neutralization test done to assess the immune status of a person. It was used in the past to know the susceptibility of individuals to Corynebacterium diphtheriae.

Answer 24

Schick test

Question 25

Schick test is performed by ________ of 0.1 mL of a purified standardized toxin. If the patient has no antitoxin, the toxin will cause inflammation at the site _______ later. If _______ occurs, anti-toxin is present and the patient is immune.

Answer 25

intradermal injection ; 4 to 7 days ; no inflammation