Figure 3.

Binding of rS1 variants by RBD-specific mAbs

(A–E) BLI was applied to evaluate the ability of each tested mAb to bind the indicated recombinant multiply mutated spike S1 subunit proteins: B.1.1.7 rS1 (Δ 69–70; Δ 144; N501Y; A570D; D614G; P681H; Figure S3B) and B.1.351 rS1 (K417N; E484K; N501Y; D614G; Figure S3C). Each of the indicated mAbs (A–E) was immobilized on protein A sensor and incubated for 180 s with B.1.1.7 (blue) or B.1.351 (red) rS1 variants or with the WT rS1 (black).

(F) Non-specific control antibody (anti-ricin MH75) was included.

The figure includes representative graphs of at least two independent repeats of each experiment, yielding similar results.