What is the Ouchterlony technique?
Ouchterlony double immunodiffusion (also known as passive double immunodiffusion) is an immunological technique used in the detection, identification and quantification of antibodies and antigens, such as immunoglobulins and extractable nuclear antigens.
What is Ouchterlony test used for?
The immunodiffusion (ID) test, also called the Ouchterlony test, allows antigen detection. Immunodiffusion refers to the movement of the antigen or antibody or both antigen and antibody molecules in a diffusion support medium.
How does the Ouchterlony test work?
The body’s defense mechanism recognizes foreign substances, or antigens, and raises specific antibodies against them. In Ouchterlony double diffusion, both antigen and antibody are allowed to diffuse into the gel. This technique can be used to test the similarity between antigens, for example in a study of evolution.
Which medium is used to carried out Ouchterlony double diffusion?
agar
They are radial immunodiffusion (the Mancini method) and double immunodiffusion (the Ouchterlony method); both are carried out in a semisolid medium such as agar.
What are some limitations of Ouchterlony?
In the absence of staining, the Ouchterlony double immunodiffusion assay is sensitive to 100ug/ml of specific antibody, however a limitation of the technique is that is requires high concentrations of both antigen and antibody and are relatively insensitive to antibodies with low affinities (Hornbeck 1991).
What is the difference between double immunodiffusion and radial immunodiffusion?
In double immunodiffusion, both antigen and antiserum together diffuses in the gel while in Single immunodiffusion only antibody is involved in the gel and only antigen diffuses in the gel.
When two antigens are identical their precipitin lines form?
When two antigens are identical their precipitin lines form You correctly answered: an arc.
When two antigens are identical their Precipitin lines form?
What is the outcome of too low or too high a concentration of antigen in double immunodiffusion?
Too low a concentration of antigen causes the precipitate to be located in the antigen well in double diffusion experiments, and too high a concentration pushes the position of equivalence into the antibody well.
What is the zone of equivalence?
: the part of the range of possible proportions of interacting antibody and antigen in which neither or but small traces of both remain uncombined in the medium.
Why is ouchterlony called double diffusion?
In the Ouchterlony double diffusion, both the antigen and the antibody diffuse toward each other in a semisolid medium to a point till their optimum concentration is reached. A band of precipitation occurs at this point.
Why does the precipitin line form?
Why does the precipitin line form? The precipitin line forms when the antigen and antibody are in optimal proportions to each other and form an insoluble precipitate.
