Fig. 2: hACE2-hIgG1 and HH-120 comparison in syncytia formation inhibition, ADCC, and ADCP activities.
From: An IgM-like inhalable ACE2 fusion protein broadly neutralizes SARS-CoV-2 variants
a HH-120 inhibited syncytia formation. Syncytia formation assay was performed by co-culturing 293T cells co-expressing the SARS-CoV-2 S protein and EGFP (S cells) with 293T cells co-expressing hACE2 and mCherry (ACE2 cells) at a 1:1 ratio. S-ACE2 interaction-mediated syncytia formation, as reflected by polykaryocytes and the mergers of green and red cells, was observed under a fluorescent microscope (20×). Mock, co-culturing 293T cells transfected with the EGFP plasmid alone with ACE2 cells; Blank, co-culturing of S cells and ACE2 cells with medium only. Green, S cells; red, ACE2 cells; blue, cell nucleus. b HH−120 mediates ADCC and ADCP against CHO-S cells. Target cells (T) (CHO-S cells) were pre-incubated with serially diluted HH-120 or hACE2-hIgG1, effector cells (E) (Jurkat-NFAT-luc2p/FcγRIIIa (F158) cells for ADCC or Jurkat-NFAT-luc2p/FcγRIIa (R131) cells for ADCP) were added at an E:T ratio of 6:1. The ADCC and ADCP activities are shown as fold induction of luciferase activity over blank control. Data shown are average values of three replicates from distinct samples. Error bars represent the SD. Data shown are representatives of three independent experiments (a, b). Source data are provided as a Source Data file.
