Table I

A comparison of different methods to validate antibodies

SPR, surface plasmon resonance; IHC, immunohistochemistry; RNAi, RNA interference; GFP, green fluorescent protein.

Antigen-basedAssays based on the antigen used for immunization (immunogen)ELISA, protein arrays, SPR, antigen adsorption
Target-basedAnalysis of native or partially denatured protein from natural sources (such as cell lysates)Western blots, IHC, immunocapture (“pull-downs”)
RNA-basedComparison of expression levels at the protein and RNA levelTranscript profiling, in situ hybridizations
DNA-basedComparison between experimental data and bioinformatics based on genome sequenceTransmembrane regions and other localization signals
Genetics-basedThe use of genetic mutants or recombinant constructions to validate the targetTransgenetics, RNAi, GFP fusions
Epitope-basedComparison of two or more antibodies directed to different parts of the same targetAntibodies to PrESTs or synthetic peptides