Absolute Antibody is glad to announce that many of their coronavirus antibodies are still potent binders of the Omicron variant (CR3022, CV1, EY6A) and can be used effectively as reagents for research and diagnostics at this stage of the pandemic. Simultaneously, several clones failed to detect the Omicron variant (CV30, Sb#15), which makes them strong candidates for the differentiating detection of certain coronavirus mutants. ELISA data showing the binding curves for each clone can be seen below, along with a summary of how the clones have performed against key coronavirus variants to date.
Antibodies that still retained affinity for the Omicron variant bound epitopes on the receptor binding domains that do not completely block ACE2 binding, while antibodies competing with ACE2 binding lost the ability to bind. This is in line with the accumulation of mutations in the ACE2 binding site of the Omicron RBD (Mannar et al, 2021).
All anti-coronavirus clones tested against the Omicron variant are available in a wide variety of engineered formats, designed to open up new experimental possibilities for in vitro and in vivo use. Some of the formats include:
- Human IgG1, IgG2, IgG3, IgG4, IgA, IgM and IgE for use in neutralization assays and as serological controls
- Rabbit, mouse, cat and ferret formats for detection applications, co-labeling studies and animal model research
- Human and mouse Fab and Fab2 formats with His-tags, for applications where antibody fragments are desirable and for site-specific functionalization
- Human IgG1 and mouse IgG2b Fc Silent™ formats, which are aimed at discerning Fc-dependent and Fc-independent effector functions and facilitating research into the role of antibody-dependent enhancement (ADE)