Two classes of molecule with therapeutic potential that are not currently addressed by antibody drugs are G-protein-coupled receptors and ion channels, largely because they display small com-ponents not accessible to traditional antibodies and their sequence is often conserved and thus less likely to be antigenic.
We are able to address the second challenge, because our Kymouse™ knockout system is in place to allow us to search for conserved epitopes.
To address the first, we have explored existing studies that show that human antibodies that are able penetrate past a heavily glycosylated surface to contact deep and conserved epitopes in viral proteins have very long CDR3s. We have used this information to reverse-engineer Kymouse™ strains in which the antibodies with longer average CDR3 loop lengths are generated more fre-quently.
These mice are a unique platform to discover antibodies that we anticipate will be able to modulate the activity of G-protein-coupled receptors, ion channels, active sites of enzymes and pathogen antigens.
Both infected cells and, in some instances, cancer cells, display degraded internal proteins on their cell surface in the context of Major Histocompatibility Complex (MHC) proteins. Proteins of this type are recognised as self or non-self by T-cell receptors on cytotoxic T-cells. The Kymouse platform has been used to isolate antibodies which recognise specific peptide-MHC complexes, providing access to a unique repertoire of new targets.