HX-MS Data Interpretation

HX-MS data analysis in epitope mapping can be laborious due to the large number of peptides generated and associated kinetic measurements (i.e., different incubation/exchange time points). Recent development in user-friendly HX-MS software (see Chapter 3) relieves scientists of many hours of arduous data analysis [56-58]. The software advancements along with the addition of automation to the standard HX-MS platform have greatly facOitated the acceptance of HX-MS technology as a suitable technique for routine characterization of therapeutic proteins. 

Currently available HX-MS software provides users with various options to visualize HX results (reviewed in Section 3.3.5). Some common options include deuterium uptake kinetic curves, heat maps [56], and butterfly plots [59]. The latter two present information such as the protein conformational dynamics and the differential deuterium uptake comparisons of full-length proteins in a single graph, making data interpretation more efficient. Anotha- informative way to interpret the HX results is to map the changes of deuterium uptake onto a known X-ray stracture of the antigen [41]. 

Utility of Hydrogen Exchange Mass Spectrometry in Epitope Mapping 253 

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