TY - JOUR
T1 - Effect of Trastuzumab-HER2 Complex Formation on Stress-Induced Modifications in the CDRs of Trastuzumab
AU - Spanov, Baubek
AU - Aboagye, Victoria
AU - Olaleye, Oladapo
AU - Govorukhina, Natalia
AU - van de Merbel, Nico C
AU - Bischoff, Rainer
N1 - Copyright © 2022 Spanov, Aboagye, Olaleye, Govorukhina, van de Merbel and Bischoff.
PY - 2021
Y1 - 2021
N2 - Asparagine deamidation and aspartic acid isomerization in the complementarity determining regions (CDRs) of monoclonal antibodies may alter their affinity to the target antigen. Trastuzumab has two hot spots for deamidation and one position for isomerization in the CDRs. Little is known how complex formation with its target antigen HER2 affects these modifications. Modifications in the CDRs of trastuzumab were thus compared between the free antibody and the trastuzumab-HER2 complex when stressed under physiological conditions at 37°C. Complex formation and stability of the complex upon stressing were assessed by size-exclusion chromatography. Deamidation of light-chain Asn-30 (Lc-Asn-30) was extensive when trastuzumab was stressed free but reduced about 10-fold when the antibody was stressed in complex with HER2. Almost no deamidation of heavy-chain (Hc-Asn-55) was detected in the trastuzumab-HER2 complex, while deamidation was observed when the antibody was stressed alone. Hc-Asp-102 isomerization, a modification that critically affects biological activity, was observed to a moderate degree when the free antibody was stressed but was not detected at all in the trastuzumab-HER2 complex. This shows that complex formation has a major influence on critical modifications in the CDRs of trastuzumab.
AB - Asparagine deamidation and aspartic acid isomerization in the complementarity determining regions (CDRs) of monoclonal antibodies may alter their affinity to the target antigen. Trastuzumab has two hot spots for deamidation and one position for isomerization in the CDRs. Little is known how complex formation with its target antigen HER2 affects these modifications. Modifications in the CDRs of trastuzumab were thus compared between the free antibody and the trastuzumab-HER2 complex when stressed under physiological conditions at 37°C. Complex formation and stability of the complex upon stressing were assessed by size-exclusion chromatography. Deamidation of light-chain Asn-30 (Lc-Asn-30) was extensive when trastuzumab was stressed free but reduced about 10-fold when the antibody was stressed in complex with HER2. Almost no deamidation of heavy-chain (Hc-Asn-55) was detected in the trastuzumab-HER2 complex, while deamidation was observed when the antibody was stressed alone. Hc-Asp-102 isomerization, a modification that critically affects biological activity, was observed to a moderate degree when the free antibody was stressed but was not detected at all in the trastuzumab-HER2 complex. This shows that complex formation has a major influence on critical modifications in the CDRs of trastuzumab.
U2 - 10.3389/fchem.2021.794247
DO - 10.3389/fchem.2021.794247
M3 - Article
C2 - 35047480
SN - 2296-2646
VL - 9
JO - Frontiers in Chemistry
JF - Frontiers in Chemistry
M1 - 794247
ER -