Table 1.

Information obtained from different epitope mapping methods

Method	Epitope type(s) mapped	Extent and resolution of map
X-ray crystallography of Ag–Ab complex	any1	entire epitope, contact residues, epitope conformation
DXMS (Ab-inhibition of hydrogen-deuterium exchange in the Ag)	peptidic	entire epitope, small segments containing the contact residues
STD NMR (Ab-induced alteration of the NMR spectrum of the Ag)	any	contact residues
Glycan array probing or oligosaccharide competition for Ab-binding	glycan and glycopeptidic	entire epitope (glycan) or partial epitope (glycopeptidic), contact residues if oligosaccharides differing by one sugar are available; otherwise – small segments containing the contact residues
Peptide scanning (of Ag peptides) or testing of Ag fragments for Ab binding	peptidic	usually partial epitope, small segments containing some of the contact residues
Mutagenesis (alanine shaving, alanine scanning, point or deletion mutations) and testing for Ag–Ab binding	peptidic and glycopeptidic	partial epitope, critical contacts
EM or cryoEM of Ag–Ab complex	any	epitope region
Experimentally validated computational docking of Ag–Ab complex (constrained by data from other methods)	any	entire epitope, contact residues, epitope conformation

Ab, antibody; Ag, antigen; cryoEM, cryoelectron microscopy; DXMS, deuterium exchange/mass spectrometry; EM, electron microscopy; STD NMR, saturation transfer difference nuclear magnetic resonance.

¹Including peptidic, glycan, lipid, nucleic acid, or combinations thereof.