Bio-Rad Laboratories and Integral Molecular are offering a system that quickly and reproducibly characterises the binding affinities of antibodies to diverse integral membrane proteins.
Integral Molecular developed the Lipoparticle, which enables integral membrane protein interactions to be measured using Bio-Rad's label-free, high-throughput Proteon XPR36 Protein Interaction Array System.
Understanding antibody-binding characteristics is critical for screening new drug candidates and developing reagents that achieve optimal pharmacological characteristics.
Current methods for measuring the binding affinity of ligands to transmembrane proteins require the use of whole cells or cell membrane preparations, which are heterogeneous and too impure to generate high-quality reproducible biosensor data.
The challenges with these methods have constrained the study of ligand binding strengths to a limited number of integral membrane proteins.
Integral Molecular's proprietary Lipoparticle technology offers scientists working with membrane-bound targets a standardised reagent with higher concentrations of membrane proteins than cell-membrane preparations.
Lipoparticles exploit the self-assembling machinery of non-infectious viral core proteins to create non-living, stable, homogenous nanoparticles comprising a lipid bilayer incorporating highly concentrated target receptors.
Because the lipid bilayer is derived directly from mammalian cells, the incorporated membrane proteins are structurally intact and correctly oriented.
At purities up to 100-fold those of cell-membrane preparations, a wide range of membrane proteins have been validated for use in biosensors as targets and as analytes.
Bio-Rad's Proteon XPR36 is a multiplexed 6x6 SPR array that permits the label-free kinetic analysis of 36 different protein interactions in a single experiment, more than any other system.
When used in combination, Lipoparticles and the Proteon will enable scientists to rapidly and reproducibly screen membrane-protein targeting antibodies for binding characteristics.
Integral Molecular offers Lipoparticles as a product for customers to study their own membrane protein interactions and also offers services using Bio-Rad's Proteon instrument.
Customers can submit sequences of integral membrane proteins to Integral Molecular, which will incorporate the proteins into Lipoparticles.
Lipoparticles can then be coupled to the Proteon sensor surface and by flowing customers' monoclonal antibodies across the chip, it is possible to measure overall binding strength (affinity, KD) and individual molecular association and dissociation rates (binding kinetics, kon and koff).
Renee LeMaire-Adkins, a marketing manager for Bio-Rad, said: 'Combining Bio-Rad's Proteon system with Integral Molecular's Lipoparticles results in a high-throughput workflow for screening highly concentrated, native membrane protein targets and their binding partners in hours instead of days.' Integral Molecular said the system is ideal for early-stage drug discovery researchers interested in rapidly identifying and characterising monoclonal antibody therapeutics.
