利用两种先进的生物物理技术表征弱结合反应:氢氘交换质谱(HDX-MS)以及差式扫描量热(DSC)

Dile Holton， PhD1Colette Quin， PhD.1Joomi Ahn2St John Skilton，PhD2Ying Qing Yu， PhD"器信息网 Characterizing Weak Binding Events with TwoAdvanced Biophysical Techniques： HydrogenDeuterium Exchange (HDX-MS) and DifferentialScanning Calorimetry(DSC) Background： The objective of this study was to probe the conformational change caused bya site specific mutation in a human immunoglobuin G (lgG). Hydrogen-Deuterium Exchange Mass Spectrometry (HDX-MS) andDifferential Scanning Calorimetry (DSC) complement one another and havethe laboratory-proven sensitivity and reproducibility to successfullycharacterize the structure and function of binding molecules. The HDX-MS/DSC data sets enabled a clear， comprehensive characterizationof peptide maps and thermodynamic stability changes that help define weakbinding events. HDX-MS Experiments/Data Pulsed Labeling Denaturant + c 2.0 HDX-MS data for Variant 1 & 2 indicates 3 AA substitutioninfluences molecular structure Effective mapping of engineered changes in weak bindingsites 1- TAInstruments， New Castle， DE；2-Waters LLC， Milford， MA (A) nanoACQUITY UPLC HDX -Waters (B) Xevo G2 Q-TOF MS -Waters (C) Nano DSC Autosampler System- TA Instruments DSC Experiments / Data Temperature(C) Tm AHyH1 Tm2 AHvH2 Tm： AHvH3 (℃) (kJ/mol) Aw(℃) ( (kJ/mol) Aw2(C) (kJ/mol) Aws Var 1 57.6 376 1.4 83.4 444 4.7 88.4 640 1.4 Var 2 57.8 406 1.6 83.1 420 5.6 889.0 557 2.1 control 65 477 1.1 83.6 410 5.3 889.1 619 1.8 °Tm shift in Variant 1 & 2 indicates molecular structure changes inweak binding sites ° Data from DSC thermogram consistent with HDX-MS data Summary / Conclusion： A combination of HDX-MS and DSC is capable of revealing importantstructural details for biopharmaceuticals that cannot be obtained using othertechniques HDX can map changes in binding regions and define structure of weakbinding sites DSC characterization ensures highest quality structural data fordifferentiating weak binding molecular variants HDX-MS & DSC provide powerful， flexible analysis tools for DD， R&Dand QC