Peters, Shirley J. and Smales, C. Mark and Henry, Alistair J. and Stephens, Paul E. and West, Shauna and Humphreys, David P. (2012) Engineering an Improved IgG4 Molecule with Reduced Disulfide Bond Heterogeneity and Increased Fab Domain Thermal Stability. Journal of Biological Chemistry, 287 (29). pp. 24525-24533. ISSN 0021-9258. (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)
The integrity of antibody structure, stability, and biophysical characterization are becoming increasingly important as antibodies receive increasing scrutiny from regulatory authorities. We altered the disulfide bond arrangement of an IgG4 molecule by mutation of the Cys at the N terminus of the heavy chain constant domain 1 (CH1) (Kabat position 127) to a Ser and introduction of a Cys at a variety of positions (positions 227–230) at the C terminus of CH1. An inter-LC-CH1 disulfide bond is thus formed, which mimics the disulfide bond arrangement found in an IgG1 molecule. The antibody species present in the supernatant following transient expression in Chinese hamster ovary cells were analyzed by immunoblot to investigate product homogeneity, and purified product was analyzed by a thermofluor assay to determine thermal stability. We show that the light chain can form an inter-LC-CH1 disulfide bond with a Cys when present at several positions on the upper hinge (positions 227–230) and that such engineered disulfide bonds can consequently increase the Fab domain thermal stability between 3 and 6.8 °C. The IgG4 disulfide mutants displaying the greatest increase in Fab thermal stability were also the most homogeneous in terms of disulfide bond arrangement and antibody species present. Importantly, mutations did not affect the affinity for antigen of the resultant molecules. In combination with the previously described S241P mutation, we present an IgG4 molecule with increased Fab thermal stability and reduced product heterogeneity that potentially offers advantages for the production of IgG4 molecules.
|Uncontrolled keywords:||Antibodies; Antibody Engineering; Disulfide Bond; Biotherapeutic; Protein Stability; Site-directed Mutagenesis; Chinese Hamster Ovary Cells; IgG4; Thermal Stability|
|Divisions:||Faculties > Science Technology and Medical Studies > School of Biosciences|
|Depositing User:||Sue Davies|
|Date Deposited:||17 Jul 2012 09:52|
|Last Modified:||09 Jun 2014 08:33|
|Resource URI:||https://kar.kent.ac.uk/id/eprint/29892 (The current URI for this page, for reference purposes)|