Multidimensional nanobody profiling - a new platform for functional characterization of camelid immune repertoires

Camelids, including llamas and alpacas, express unique immunoglobulins composed only of heavy chains.

The antigen-binding variable fragment is a single-domain that can be recombinantly expressed as a 15 kDa functional molecule, called a “single-domain antibody” or  “nanobody”.

Nanobodies present a number of advantages over conventional antibodies, both in terms of what they can do, but also in the set of approaches that can be used for their discovery.This proposal builds upon our recent work that discovered a number of exceptionally potent nanobodies, some of which potently cross-neutralized all SARS-CoV-2 variants of concern that were circulating at the time, as well as SARS-CoV-1.With this short (2-year) project, the three participating labs propose to take that methodological foundation, which established a next-generation sequencing (NGS) based high-throughput nanobody platform, and extend it in multiple ways.

The key focus of our approach is that an initial nanobody library can be screened under multiple different conditions (against different antigens fragments, or different antigen variants, using sandwich or competition techniques, etc), and the enrichment metrics for these can be digitally integrated to provide a functional profiles of all nanobodies in an immune repertoire.Our wetlab and computational improvements to the platform will expand the range of potential applications, and lay a solid foundation for future therapeutic discovery work.