Figure 4.

Specific Interactions between SARS-CoV-2-S1 and SARS-CoV-2-CTD with hACE2, Characterized by SPR

The indicated mFc-tagged proteins in the supernatant were captured by anti-mIgG antibodies that were immobilized on the chip and subsequently tested for binding with gradient concentrations of hACE2 or hCD26, with the following binding profiles shown.

(A) SARS-RBD binding to hACE2.

(B) SARS-RBD binding to hCD26.

(C) MERS-RBD binding to hACE2.

(D) MERS-RBD binding to hCD26.

(E) SARS-CoV-2-S1 binding to hACE2.

(F) SARS-CoV-2-S1 binding to hCD26.

(G) SARS-CoV-2-NTD binding to hACE2.

(H) SARS-CoV-2-NTD binding to hCD26.

(I) SARS-CoV-2-CTD binding to hACE2.

(J) SARS-CoV-2-CTD binding to hCD26.

(K) Culture supernatant of HEK293T cells without transfection (NC) binding to hACE2.

(L) Culture supernatant of HEK293T cells without transfection (NC) binding to hCD26.

The values shown are the mean ± SD of three independent experiments.