By Gerald Platteau, Guido Ströhlein, Vaiva Gaspariunaite, Cécile Vincke, Yann Sterckx, and Serge Muyldermans
The standard capture purification of full-size, classical antibodies is typically performed with Protein A affinity chromatography. Binding of the Protein A affinity ligand to the “Fc” region of antibodies (Abs) takes place at the juncture of the constant domains 2 and 3 of the Ab heavy chains (Lewis et al. 2008). This high affinity binding primarily involves hydrophobic interactions. Antibodies that belong to the same subclass have greater than 95% homologous Fc-regions, allowing Protein A to be a capture platform for a wide range of antibodies (Ghose et al. 2005).