Recognize only a particular or restricted epitope on an antigen
Can have batch-to-batch variability
Once a hybridoma is made, it is a constant and renewable source
Low batch-to-batch variability
Recognize multiple epitopes on any one antigen. Serum obtained will contain a heterogeneous complex mixture of antibodies of different affinity.
Polyclonals are made up mainly of IgG subclass.
Peptide immunogens are often used to generate polyclonal antibodies that target unique epitopes, especially for protein families of high homology.
Inexpensive and relatively quick to produce.
Production is less complex compared with monoclonal antibodies.
Polyclonal antibodies recognize multiple epitopes on any one antigen. This has the following advantages:
Polyclonals amplify the signal from a target protein with low expression level, as the target protein will bind more than one antibody molecule on the multiple epitopes. However, this is less advantageous for quantification experiments (eg in flow cytometry) as it generates inaccurate results.
More tolerant of minor antigen changes (eg polymorphism, heterogeneity of glycosylation or slight denaturation) than monoclonals.
Can identify proteins of high homology to the immunogen protein, and can be used to screen for the target protein in species other than that of the immunogen.
Often the preferred choice for detecting denatured proteins.
Prone to batch-to-batch variability.
Less useful for probing specific domains of an antigen because antiserum will usually recognize many domains.
Detect only a particular or restricted epitope on the antigen.
Consist of only one antibody subtype (eg IgG1, IgG2, IgG3).
Hybridomas are a constant and renewable source once created, and all batches will be identical, increasing consistency and standardization of experimental procedures and results.
Monoclonals detect one epitope per antigen. This has the following advantages:
Monoclonals specifically detect a particular or defined/restricted epitope on the antigen, which means they are less likely to cross-react with other proteins.
Homogeneity of monoclonal antibodies is high. If experimental conditions are kept constant, results from monoclonal antibodies can be highly reproducible between experiments.
The epitope may not be shared across a range of species.
More vulnerable to the loss of epitope through chemical treatment of the antigen than polyclonal antibodies. This can be offset by pooling two or more monoclonal antibodies to the same antigen (eg cocktail antibodies).