Antibody Expression, Purification, Structure Determination, and Engineering

Through the use of mammalian cell expression systems, we are able to express and purify a variety of monoclonal antibodies. Mammalian cells offer the advanced folding and post-translational modifications that are required for producing antibodies that have similar properties to those produced in the human body. Our facility has the ability to express, purify, and optimize the function of recombinant antibodies.

Purification of Antibodies

Antibody purification is performed through specific isolation or selective enrichment. Monoclonal antibodies are purified from a cell culture supernatant. Using our numerous FPLC machines, we are able to purify antibodies through size exclusion chromatography, ion-exchange chromatography, and affinity chromatography.

Size exclusion chromatography separates particles within the sample mixture based on the size of each particle. Ion exchange chromatography uses charged resins (positively charged or negatively charged) to bind proteins based on their net charges within a specific buffer. Affinity chromatography is done using antibody-binding ligands (Protein A, G, and L) that are covalently attached onto porous resins (beaded agarose). The protein of interest attaches to these ligands while other material is washed away. An acidic buffer is then used to allow the antibody to dissociate from the resin, thus isolating it in a purified state.

Structure Determination via Crystallography or Cryo-EM

We have determined high-resolution structures of antibody, antigen/antibody complex. A routine process of structural biology for antibody and antigen have been well developed. Except structure delivery, we will also figure out CDRs, key interactions between antibody and antigen, and provide insights how to improve affinity, specificity and stability.

Antibody Engineering, Biospecific Antibody Design and ADC Site Optimization

Techniques used at Structure Based Design allow us to modify antibodies using protein engineering to enhance their functionality. The antibody of interest can be reconfigured into a variety of different formats. Through various techniques, the antibody can either be directly modified or engineered to suit its specific application.