Genovis seeks to provide enzymes and solutions for the characterisation of antibodies or antibody-based formats with the aim of expanding into other formats. Philip Widdowson, Global Product Manager at Genovis, explained that the large and small molecule landscape has become more exciting and unpredictable over the last decade, meaning that solution providers like Genovis must find innovative ways to keep up.
Widdowson discussed antibody digestion tools for hinge-mutated antibodies. Genovis strongly focuses on mid-level analysis: “Rather than digesting down to the peptide level, we can digest at the middle level, digest at the hinge of the antibody to do mid-level characterisation.” He then highlighted a case study that digests below the hinge region to get the FD prime light chain, single chain FC, and subunits for high-resolution mass spectrometry.
The hinge mutations involved in modulating the FC effector function either silence or enhance the function to promote the activation of different effector functions or suppress them. FabRICATOR, an enzyme developed by Genovis, can silence mutations in the hinge. However, the specificity of this enzyme is limited when it comes down to the nitty-gritty parts of the hinge, so the company developed FabRICATOR Xtra to address the challenges of digesting hinge-mutated antibodies.
FabRICATOR Xtra was tested on several mutated antibodies, including LALAPG, D265A, and D265S, and allows customers to perform below-hinge digestion. Although some mutations prevent efficient digestion optimisation may be required depending on the mutation.
Widdowson then mentioned that alternative enzymes such as FabDELLO, GingisKHAN, and FabALACTICA can digest above the hinge, providing a solution for antibodies that FabRICATOR Xtra struggles with. Furthermore, these enzymes can be used for chain characterisation of bispecific and multi-specific molecules. Widdowson concluded with a call for collaboration with customers to help Genovis access molecules and develop enzymes that can efficiently digest mutated antibodies.
