tetano
Editor, Senior Moderator
Front Immunol
. 2022 May 4;13:868724.
doi: 10.3389/fimmu.2022.868724. eCollection 2022.
Antigenic Cross-Reactivity Between SARS-CoV-2 S1-RBD and Its Receptor ACE2
Yen-Chung Lai[SUP] 1 2 [/SUP], Yu-Wei Cheng[SUP] 2 3 [/SUP], Chiao-Hsuan Chao[SUP] 1 [/SUP], Yu-Ying Chang[SUP] 2 [/SUP], Chi-De Chen[SUP] 4 [/SUP], Wei-Jiun Tsai[SUP] 3 [/SUP], Shuying Wang[SUP] 5 [/SUP], Yee-Shin Lin[SUP] 5 [/SUP], Chih-Peng Chang[SUP] 5 [/SUP], Woei-Jer Chuang[SUP] 6 [/SUP], Li-Yin Chen[SUP] 2 [/SUP], Ying-Ren Wang[SUP] 2 [/SUP], Sui-Yuan Chang[SUP] 7 [/SUP], Wenya Huang[SUP] 1 [/SUP], Jen-Ren Wang[SUP] 1 [/SUP], Chin-Kai Tseng[SUP] 8 [/SUP], Chun-Kuang Lin[SUP] 8 [/SUP], Yung-Chun Chuang[SUP] 1 2 9 [/SUP], Trai-Ming Yeh[SUP] 1 [/SUP]
Affiliations
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging virus responsible for the ongoing COVID-19 pandemic. SARS-CoV-2 binds to the human cell receptor angiotensin-converting enzyme 2 (ACE2) through its receptor-binding domain in the S1 subunit of the spike protein (S1-RBD). The serum levels of autoantibodies against ACE2 are significantly higher in patients with COVID-19 than in controls and are associated with disease severity. However, the mechanisms through which these anti-ACE2 antibodies are induced during SARS-CoV-2 infection are unclear. In this study, we confirmed the increase in antibodies against ACE2 in patients with COVID-19 and found a positive correlation between the amounts of antibodies against ACE2 and S1-RBD. Moreover, antibody binding to ACE2 was significantly decreased in the sera of some COVID-19 patients after preadsorption of the sera with S1-RBD, which indicated that antibodies against S1-RBD can cross-react with ACE2. To confirm this possibility, two monoclonal antibodies (mAbs 127 and 150) which could bind to both S1-RBD and ACE2 were isolated from S1-RBD-immunized mice. Measurement of the binding affinities by Biacore showed these two mAbs bind to ACE2 much weaker than binding to S1-RBD. Epitope mapping using synthetic overlapping peptides and hydrogen deuterium exchange mass spectrometry (HDX-MS) revealed that the amino acid residues P463, F464, E465, R466, D467 and E471 of S1-RBD are critical for the recognition by mAbs 127 and 150. In addition, Western blotting analysis showed that these mAbs could recognize ACE2 only in native but not denatured form, indicating the ACE2 epitopes recognized by these mAbs were conformation-dependent. The protein-protein interaction between ACE2 and the higher affinity mAb 127 was analyzed by HDX-MS and visualized by negative-stain transmission electron microscopy imaging combined with antigen-antibody docking. Together, our results suggest that ACE2-cross-reactive anti-S1-RBD antibodies can be induced during SARS-CoV-2 infection due to potential antigenic cross-reactivity between S1-RBD and its receptor ACE2.
Keywords: COVID-19; angiotensin converting enzyme 2; autoantibody; molecular mimicry; monoclonal antibody.
. 2022 May 4;13:868724.
doi: 10.3389/fimmu.2022.868724. eCollection 2022.
Antigenic Cross-Reactivity Between SARS-CoV-2 S1-RBD and Its Receptor ACE2
Yen-Chung Lai[SUP] 1 2 [/SUP], Yu-Wei Cheng[SUP] 2 3 [/SUP], Chiao-Hsuan Chao[SUP] 1 [/SUP], Yu-Ying Chang[SUP] 2 [/SUP], Chi-De Chen[SUP] 4 [/SUP], Wei-Jiun Tsai[SUP] 3 [/SUP], Shuying Wang[SUP] 5 [/SUP], Yee-Shin Lin[SUP] 5 [/SUP], Chih-Peng Chang[SUP] 5 [/SUP], Woei-Jer Chuang[SUP] 6 [/SUP], Li-Yin Chen[SUP] 2 [/SUP], Ying-Ren Wang[SUP] 2 [/SUP], Sui-Yuan Chang[SUP] 7 [/SUP], Wenya Huang[SUP] 1 [/SUP], Jen-Ren Wang[SUP] 1 [/SUP], Chin-Kai Tseng[SUP] 8 [/SUP], Chun-Kuang Lin[SUP] 8 [/SUP], Yung-Chun Chuang[SUP] 1 2 9 [/SUP], Trai-Ming Yeh[SUP] 1 [/SUP]
Affiliations
- PMID: 35603169
- PMCID: PMC9114768
- DOI: 10.3389/fimmu.2022.868724
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging virus responsible for the ongoing COVID-19 pandemic. SARS-CoV-2 binds to the human cell receptor angiotensin-converting enzyme 2 (ACE2) through its receptor-binding domain in the S1 subunit of the spike protein (S1-RBD). The serum levels of autoantibodies against ACE2 are significantly higher in patients with COVID-19 than in controls and are associated with disease severity. However, the mechanisms through which these anti-ACE2 antibodies are induced during SARS-CoV-2 infection are unclear. In this study, we confirmed the increase in antibodies against ACE2 in patients with COVID-19 and found a positive correlation between the amounts of antibodies against ACE2 and S1-RBD. Moreover, antibody binding to ACE2 was significantly decreased in the sera of some COVID-19 patients after preadsorption of the sera with S1-RBD, which indicated that antibodies against S1-RBD can cross-react with ACE2. To confirm this possibility, two monoclonal antibodies (mAbs 127 and 150) which could bind to both S1-RBD and ACE2 were isolated from S1-RBD-immunized mice. Measurement of the binding affinities by Biacore showed these two mAbs bind to ACE2 much weaker than binding to S1-RBD. Epitope mapping using synthetic overlapping peptides and hydrogen deuterium exchange mass spectrometry (HDX-MS) revealed that the amino acid residues P463, F464, E465, R466, D467 and E471 of S1-RBD are critical for the recognition by mAbs 127 and 150. In addition, Western blotting analysis showed that these mAbs could recognize ACE2 only in native but not denatured form, indicating the ACE2 epitopes recognized by these mAbs were conformation-dependent. The protein-protein interaction between ACE2 and the higher affinity mAb 127 was analyzed by HDX-MS and visualized by negative-stain transmission electron microscopy imaging combined with antigen-antibody docking. Together, our results suggest that ACE2-cross-reactive anti-S1-RBD antibodies can be induced during SARS-CoV-2 infection due to potential antigenic cross-reactivity between S1-RBD and its receptor ACE2.
Keywords: COVID-19; angiotensin converting enzyme 2; autoantibody; molecular mimicry; monoclonal antibody.