The V-PLEX SARS-CoV-2 Panel 28 (ACE2) Kit is a multiplex assay for antibodies that block the binding of ACE2 to RBD antigens from variants of SARS-CoV-2. It includes antigens from Alpha, Beta, Delta, and several sublineages of Omicron, including BA.2, BA.2.12.1, BA.3, BA.4, BA.5, and two BA.2 RBD antigens with extra mutations predicted to further evade neutralization. Panel 28 includes: A (WT), (B.1.1.7), (B.1.351; B.1.351), (AY.3; AY.4; AY.4.2; AY.5; AY.6; AY.7; AY.12; AY.14; B.1.617.2; B.1.617.2+ΔY144), (BA.2; BA.2.1; BA.2.2; BA.2.3; BA.2.5; BA.2.6; BA.2.7; BA.2.8; BA.2.10; BA.2.10.1; BA.2.12), (BA.2.12.1), (BA.2+L452M), (BA.2+L452R), (BA.3), and (BA.4; BA.5).