Functional ELISA analysis of immobilized recombinant Spike S1 protein(s) derived from different strains of SARS-CoV-2 virus (ie., Wild type; B.1.351 beta variant; P.1 gamma variant) (coated at 2 μg/mL) binding to soluble recombinant Human ACE2 (ECD) protein, mouse IgG Fc tag (active) (GTX135683-pro) (0.16-117.19 nM). Bound protein was detected by Goat Anti-Mouse IgG antibody (HRP) (GTX213111-01) (1:10000).

1 μg of GTX136094-pro SARS-CoV-2 Spike S1 (L18F, T20N, P26S, D138Y, R190S, K417T, E484K, N501Y, D614G, H655Y), Brazil variant, His tag protein was analyzed using SDS-PAGE and stained with coomassie blue and captured by monochrome camera.

SARS-CoV-2 Spike S1 (L18F, T20N, P26S, D138Y, R190S, K417T, E484K, N501Y, D614G, H655Y), Brazil variant, His tag protein (GTX136094-pro, 0.5 μg) was separated by 12% SDS-PAGE, and the membrane was blotted with the SARS-CoV-2 (COVID-19) Spike RBD antibody [HL257] (GTX635692) diluted at 1:5000.