What is Ouchterlony double diffusion 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 happens in Ouchterlony gel diffusion?
In the Ouchterlony assay, a series of samples (the antigens) are placed in the outer wells of a gel plate, and antibodies (antiserum) are placed in the center well, after which they diffuse out and form different geometric precipitation lines in the gel (Fig. 1).
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 is Ouchterlony analysis?
The Oucherlony method is one method where a titer (concentration) of an antibody can be measured and seen. A gel is made up and the antigen and antibody diffuse across the gel towards each other.
What is the Ouchterlony test used for?
An immunodiffusion test used to determine the species from which blood or other body fluid originated. To perform the test, agarose is poured into a Petri dish and allowed to gel. A central hole is punched in the gel and sample extract containing antigens is placed in it.
What are the different antigen antibody patterns observed in a typical Ouchterlony double diffusion experiment?
Antigens from different species are loaded into two wells and the known antibody is loaded in a third well located between and slightly below the antigen wells to form a triangle. Depending on the similarity between the antigens, different geometrical patterns are produced between the antigen and antiserum wells.
What are the 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).
How the ouchterlony test detects antigens by using the antigen antibody reaction?
The Ouchterlony assay demonstrates lattice formation in a gel. The radial immunodiffusion assay is used to quantify antigen by measuring the size of a precipitation zone in a gel infused with antibodies. Insoluble antigens in suspension will form flocculants when bound by antibodies.
What does the Ouchterlony test determine?
Although there are now more sensitive and quantitative methods of detecting antibody-antigen interactions, the Ouchterlony test provides a rapid and qualitative way of determining whether an antiserum has antibodies against a particular antigen.