{{Infobox diagnostic | Name = Immunodiffusion | Image = | Caption = | ICD10 = | ICD9 = | MeshID = D005779 | OPS301 = | OtherCodes = | }} '''Immunodiffusion''' is a laboratory technique used to detect and quantify antigens and antibodies by observing their interactions within a gel medium.<ref name=":0">{{Cite web |title=Immunodiffusion - Protocol & Troubleshooting - Creative Biolabs |url=https://www.creativebiolabs.net/immunodiffusion.htm |access-date=2024-07-25 |website=www.creativebiolabs.net}}</ref> This technique involves the diffusion of antigens and antibodies through a gel, usually agar, resulting in the formation of a visible precipitate when they interact.<ref name=":0" /><ref name=":1">{{Cite web |last=Aryal |first=Sagar |date=2022-07-04 |title=Radial Immunodiffusion- Principle, Procedure, Results, Uses |url=https://microbenotes.com/radial-immunodiffusion/ |access-date=2024-07-25 |website=microbenotes.com |language=en-US}}</ref>
== Applications == Immunodiffusion techniques are widely used in immunology for various purposes, including:<ref name=":0" /><ref name=":1" />
* Determining antigen content * Identifying immunoglobulin classes * Evaluating antibodies * Estimating serum transferrin and alpha-fetoprotein levels * Comparing properties of different antigens
== Types of Immunodiffusion ==
=== Single Immunodiffusion (Radial Immunodiffusion) === In this method, antibodies are uniformly distributed in an agar gel, and the antigen sample is placed in wells cut into the gel. As the antigen diffuses radially, it forms a precipitation ring with the antibody. The diameter of this ring corresponds to the concentration of the antigen in the solution.<ref>{{cite web |year=2017 |title=Radial Immunodiffusion |url=http://www.edvotek.com/273_gallery.png |url-status=dead |archive-url=https://web.archive.org/web/20170807195715/http://www.edvotek.com/273_gallery.png |archive-date=2017-08-07 |access-date=2017-08-07 |publisher=Edvotek, Inc. |format=photograph}} Photograph of precipitin circles in a Petri dish during radial immunodiffusion.</ref><ref name=":1" />
=== Double Immunodiffusion (Ouchterlony Technique) === This method involves both antigen and antibody diffusing through the gel from separate wells, forming precipitation lines where they meet and react.<ref>{{cite web |title=Diffusion Patterns |url=https://image.slidesharecdn.com/immunodiffusion-130121011208-phpapp01/95/immunodiffusion-principles-and-application-17-638.jpg |url-status=live |archive-url=https://web.archive.org/web/20191211044657/https://image.slidesharecdn.com/immunodiffusion-130121011208-phpapp01/95/immunodiffusion-principles-and-application-17-638.jpg |archive-date=2019-12-11 |access-date=2017-05-19 |work=Immunodiffusion principles and application}} Photographs of Ouchterlony immunodiffusion patterns showing stained precipitin lines of full identity, partial identity and non-identity.</ref>
==== Other types ==== :# Single diffusion in one dimension (Oudin procedure) :# Double diffusion in one dimension (Oakley Fulthorpe procedure)
== Advantages == * '''Cost-Effective:''' Immunodiffusion assays are relatively inexpensive compared to other immunoassays.
* '''Reliable and Reproducible:''' Provide consistent and reproducible results, making them suitable for routine diagnostic use.<ref name=":0" />
== Limitations == * '''Time-Consuming:''' The diffusion process can take several hours to days to complete.
* '''Sensitivity:''' While specific, the sensitivity of immunodiffusion may be lower compared to other methods like ELISA.<ref>{{Cite journal |last1=Mujtaba |first1=Mustafa G. |last2=Baliban |first2=Tara |last3=Bhagu |first3=Jamini |last4=Herrera |first4=Michael |title=A Laboratory Exercise Simulating Antibody and Antigen Reactions of the Ouchterlony Double Immunodiffusion Assay Using Inorganic Salts |journal=Journal of Microbiology & Biology Education |date=2021 |volume=22 |issue=2 |pages=e00103–21 |doi=10.1128/jmbe.00103-21 |doi-access=free|issn=1935-7877 |pmc=8442017 |pmid=34594450}}</ref>
==Notes== {{reflist}} ==External links== * {{MeshName|Immunodiffusion}}
{{Immunologic techniques and tests}}
Category:Biological techniques and tools Category:Diagnostic virology Category:Immunologic tests
{{immunology-stub}}