Author Archives: Gerald Platteau

Ask the Expert: Purification of Antibody Fragments Using Amsphere A3 Protein A Resin

In an “Ask the Expert†webinar on 13 September 2017, Gerald Platteau of JSR Life Sciences described the use of Amsphere A3 resin to purify antibody fragments. He explained the molecular binding mechanism for VHH singledomain antibodies and compared dynamic binding capacity (DBC) data with those of other affinity resins. Platteau’s Presentation For full-size monoclonal antibodies (MAbs), the standard capture step is based on protein A. Its binding to the Fc region has been well described as taking place at…

Purification of Antibody Fragments with Amsphereâ„¢ A3 Protein A Resin

The binding mechanism between the engineered C domain of the Amsphereâ„¢ A3 protein A (PrA) ligand and a VHH single domain antibody (sdAb) was revealed. Binding sites in the PrA ligand in helices 2 and 3 and in framework regions 1 and 3 of the VHH were confirmed. Identified VHH residues are not involved in antigen recognition. Overlap with a human VH showed the same interaction sites. These results provide insight on why Amsphere A3 is a suitable tool for…