Due to the price and performance, polyclonal antibodies are often preferred in laboratories. Properly prepared and characterized polyclonal antibodies are excellent reagents and when affinity purified they can easily compete with monoclonal antibodies in most applications. The main reason of preferring polyclonal antibodies over monoclonal antibodies is that polyclonal antibodies recognize multiple epitopes on any one antigen and the apparent interaction between these antibodies and antigens is strong. This consequently results in higher sensitivity, raising the possibilities of the antigen to be recognized after proteolytic processing. These are important for applications such as immunoblotting from SDS-PAGE and immunohistochemistry.
Monoclonal VS Polyclonal Antibodies
-Monoclonal antibodies are generally expensive to produce as advance technology is required for their production and extraction. Added to the costs is the extensive training that needs to be conducted for using the technology.
-Forming hybrid cell lines by fusing monoclonal antibodies with a myeloma cell takes much longer, although they might be able to produce a large amount of monoclonal antibodies, these antibodies are sometimes too specific.
-Monoclonal antibodies highly specified toan indiviual epitope (recognition sites) on an antigen. The serum obtained consists of merely one antibody type.
-Once a monoclonal antibody hybridoma is made, it is a consistent and renewable source of creating identical batches.
-Comparatively, the production and extraction of polyclonal antibodies is economical, they require minimal production technology minimal training needs to use the technology, consequently, lower laboratory costs.
-Polyclonal antibodies produce large amounts of antibodies which are non-specific.
-Polyclonal antibodies are able to recognize multiple sites on an antigen. The serum obtained contains a number of different antibodies of different affinity.
-Unlike monoclonal antibodies, there can be variability in the batches of polyclonal antibodies.
Why Do Laboratories Prefer Polyclonal Antibodies?
The basic reason why polyclonal antibodies are preferred over monoclonal antibodies is that they are able to recognize multiple epitopes on any one antigen.
Amplifying Signals– keeping the expression level low, polyclonal antibodies help to amplify signals from the target protein, because polyclonal antibodies recognize more than one epitopes, the target protein will bind with more than one antibody molecule on the different epitopes. This is a great advantage for experiments regarding quantification like flow cytometry.
Multiple Epitopes– Due to the ability of polyclonal antibodies to target multiple epitopes on a single antigen, they can give substantially better results in Immunoprecipitation and Chromatin immunoprecipitation.
More Tolerant To Changes– Polyclonal antibodies are more tolerant to changes in the antigen like minor denaturation or polymorphism.
Identification Of Proteins– Polyclonal antibodies identify high homology proteins to screen for the target proteins in the sample tissue from species which are different from the immunogen. More than often, polyclonal antibodies are used when the nature of an antigen in a species is unknown. This also aids in detecting any cross-reactivity in the sequence of an immunogen.
Detection– Polyclonal antibodies are extensively used to detect proteins which are denatured and multiple epitopes also allow for more efficient detection.
Why not monoclonal antibodies?
Specific– Although monoclonal antibodies can be produced in large quantities, but they are too specific and the chances for detection across a range of species is less likely.
Vulnerable– Compared to polyclonal antibodies, monoclonal antibodies are more vulnerable to the loss of epitopes through chemical treatment of antigens.
Polyclonal Or Monoclonal?
For immunoassays where high sensitivity is required, polyclonal antibodies are perfect. Polyclonal antibodies are also preferable over monoclonal antibodies in activity neutralization assays and immunoprecipitation.
Given these additional benefits over monoclonal antibodies and considering the fact that polyclonal antibodies don’t really require much of advanced technology, facility or training, that is why laboratories prefer polyclonal over monoclonal antibodies. There is a lot that can be done using polyclonal antibodies because they aren’t specific and they are also able to target multiple epitopes.
Affinity Biological Inc. has successfully immobilized polyclonal antibodies to resins to specifically immune-deplete target proteins from citrated plasma and to recover the target proteins with substantial recovery in activity.
For any query and product related information, feel free to contact Affinity Biological Inc. .