Periodic countercurrent (PCC) processes increasingly are being evaluated as alternatives to single-column batch capture processes. Some of the advantages of PCC processes over single-column processes include shortening of processing time and/or reduction of required resin volume through increased productivity; reduction in resin costs through improved resin capacity use; and reduction in buffer consumption through increased column loading. Those advantages, however, come with increased equipment complexity and hardware costs. PCC processes and systems with two to up 16 columns of the…
Author Archives: Thomas Muller-Spath
Affinity Capture of F(ab’)2 Fragments: Using Twin-Column Countercurrent Chromatography
Antibody fragments are potent active drug substances (1–4). Because they lack glycosylation, they can be produced using different biological expression systems, including yeast and microbial systems as well as mammalian cells. These molecules are interesting as biopharmaceuticals because they are smaller than full-size antibodies and therefore may penetrate better into different tissues. Antibody fragments are cleared faster in biological systems because they lack the Fc antibody structural region (4). However, fragments may be conjugated to increase their size for improved…
Purifying Common Light-Chain Bispecific Antibodies
A bispecific antibody can bind two different antigens. Immunoglobulin G (IgG) type antibodies have two binding sites with different variable regions. An IgG variable region is made up of a variable light-chain sequence (VL) and a variable heavy-chain sequence (VH). The light chains (LCs) of common LC antibodies are identical for both variable regions, leaving the heavy chain (HC) for generating different specificities. Thus, recombinant host cells for production of common LC bispecific antibodies carry genes for both HCs, with…