Figure 3.
Effects of Fc modification on the ADE activity of JMB2002. (a) Binding of Ab2001.08 and JMB2002 to FcγRs was determined by BLI. His-tagged FcγR was loaded onto the HIS1K sensor, and serially diluted antibodies bound to the receptor on the biosensor. KD values were determined with Octet Data Analysis HT 11.0 software using a 1:1 global fit model. (b-d) ADE activity was measured using a pseudotyped SARS-CoV-2 system containing a luciferase reporter. Pseudotyped viruses were preincubated with serially diluted antibodies for 1 h. The mixture was added to FcγR-expressing cells and incubated at 37°C for 20–28 h. Infection of cells with pseudotyped SARS-CoV-2 was assessed by measuring cell-associated luciferase activity. Trastuzumab was used as the irrelevant IgG control