id author title date pages extension mime words sentences flesch summary cache txt cord-278869-7zr1118b Ravichandran, Supriya Antibody repertoire induced by SARS-CoV-2 spike protein immunogens 2020-05-13 .txt text/plain 2370 142 52 To better understand antibody response induced by spike protein-based vaccines, we immunized rabbits with various SARS-CoV-2 spike protein antigens: S-ectodomain (S1+S2) (aa 16-1213), which lacks the cytoplasmic and transmembrane domains (CT-TM), the S1 domain (aa 16-685), the receptor-binding domain (RBD) (aa 319-541), and the S2 domain (aa 686-1213 as control). The spike ectodomain (S1+S2) generated antibodies that predominantly bound to S1+S2 108 6 (black bar), followed by the S1 protein (blue bar), and 3-fold lower antibody binding to the RBD 109 and the S2 domain (red and green bars, respectively) (Fig. 1D ). Antibody off-rate constants, which describe the fraction of antigen-antibody complexes 119 that decay per second, were determined directly from the serum sample interaction with SARS-120 CoV-2 spike ectodomain (S1+S2), S1, S2, and RBD using SPR in the dissociation phase only for 121 sensorgrams with Max RU in the range of 20-100 RU (Suppl. ./cache/cord-278869-7zr1118b.txt ./txt/cord-278869-7zr1118b.txt