SECONDARY REACTION 3.1 Agglutination Reaction

Question 1

• a process in which particulate antigens are linked together by their corresponding antibody.

Answer 1

Agglutination

Question 2

Is similar to precipitin reactions except that the union of antibody occurs with suspended particulate antigens rather than soluble antigens.

Answer 2

Agglutination

Question 3

Particulate antigens:

Answer 3

1. Bacteria
2. Yeasts
3. Fungi
4. RBC
5. Other microbial organisms

Question 4

If antigen ______, it is adsorbed/coated on a carrier particle to indicate visibly that the antigen-antibody reaction has taken place, i.e.,

a. Rbc
b. Latex particles
c. Bentonite
d. Colloidal charcoal
e. Collodion

Answer 4

is not particulate

Question 5

Particulate antigens:

Answer 5

Agglutination of RBC
Agglutination of Bacteria
Agglutination of Latex Particles

Question 6

➢ ________ – a method of coupling using Tannic acid
➢ ________ - the appearance of visible precipitates in a previously clear solution, as a result of Ag-Ab union.
➢ In ______ – clumping of antigen particles are visible prior to immune reaction.
➢ _____– the participating antibody, i.e. IgM
➢ _________ – the participating antigen.
➢ Agglutination reaction is influenced by the number of _________ and is subject to prozone and post-zone

Answer 6

Tanned Cell Technique
Precipitation
Agglutination
Agglutinin 
Agglutinogen
antigenic determinants

Question 7

The ratio of antigen/antibody

Antibody excess –>
Optimal ration of Equivalence –>
Antigen excess –>

Answer 7

Prozone (Soluble immune complexes)
Zone of Equivalence (Insoluble precipitate)
Postzone (Soluble immune complexes)

Question 8

Main Requirements of Agglutination Tests:

Answer 8

1. Availability of a stable cell or particulate suspension
2. The presence of one or more antigenic determinants close to the surface.
3. That non-agglutinating antibodies are not detectable without modification

Question 9

1. Availability of a stable cell or particulate suspension –
   a. Cell - rbc, yeasts, bacteria (act as biological carriers)
   b. Synthetic carriers, i.e.,
   ● Latex particles
   ● Collodion
   ● Gelatin particles
   ● Bentonite
   ● Colloidal charcoa

Question 10

The quality of test results depends on the following technical factors:

1. ________ with the antibody source (patient’s serum)
2. _________ of an antigen conjugated to the carrier.
3. Conditions of the test environment
   a. _____ - increase or decrease may affect the reaction
   ● IgG – _____
   • IgM – _____
   b. pH - ____
   c. ____ - shaking, stirring, centrifugation
   d. Class of antibody - ___ is a much better agglutinating antibody

Answer 10

Time of incubation
Amount and validity

Temperature
a. 30oC -37oC
4 – 27oC

b. 6.7 – 7.2
c. Motion
d. IgM

Question 11

Agglutination may be performed using:

a. ____ - more rapid with most procedures requiring 2-3 minutes of rotation at room temperature.
b. ____ - generally require longer incubation time (15 min to overnight)
c. ______ - an adaptation of the tube procedure

Answer 11

Slide
Tube
Microtiter techniques

Question 12

Advantages of Agglutination Tests:

a. High degree of _____
b. A _________ can be detected

Answer 12

sensitivity

wide variety of antigens