Flow cytometry analysis of NeoCoV and PDF-2180 RBD-hFc binding efficiencies with HEK293T cells transiently expressing the six non-supportive mammalian ACE2 and corresponding 305E mutants. The red dashed lines: the threshold for positive cells set by vector control. a, b 305E related mutants; c, d Sape and Sbol ACE2 related mutants; e, f Pcin ACE2 related mutants. Schematic illustrations of Pcin ACE2 mutants carrying substitutions of Ppip counterparts were shown in e. Data are presented as means +/- SD for n = 3 biologically independent cells for a. Data are presented as means +/- SEM for n = 3 biologically independent cells for b, d, and f. Data representative of two independent experiments for b - f. Two-tailed unpaired Student’s t -test; * P < 0.05, ** P < 0.01, *** P < 0.005, and **** P < 0.001, NS not significant. RLU relative light unit. Scale bars represent 100 m for c and e.
