Publication date: Jun 15, 2025

The unique antibodies target an essential highly conserved site at the base of the virus’s spike protein, effectively clamping it shut and preventing the virus from infecting cells. And when researchers attempted to force the virus to evolve resistance, the virus struggled, producing only rare escape variants that were much less infectious. They latch onto the poorly exposed, highly conserved region (a coiled coil of 3 alpha helices) at the base of the virus’s spike protein. Scientists have discovered a unique class of small antibodies that are strongly protective against a wide range of SARS coronaviruses, including SARS-CoV-1 and numerous early and recent SARS-CoV-2 variants. Llamas generate so-called single-domain antibodies, also known as VHHs or nanobodies, that are much smaller than the antibodies generated by most animals, including humans. This points to a powerful, hard-to-evade treatment option. This region is so crucial to the virus that it can’t easily mutate without weakening the virus itself. “The combination of high potency, broad activity against numerous viral variants, and a high barrier to resistance is incredibly promising,” adds Saelens.

Semantics

Original Article