Stable recombinant expression of the anti HIV-1 monoclonal antibody 2F5 after IgG3/IgG1 subclass switch in CHO cells

The human monoclonal antibody (humAb) 2F5 is a potent candidate for immunot herapy of HIV-1. The xenohybridoma derived humAb 2F5 is of IgG3 kappa isoty pe. Generally, IgG1 isotype has a longer half-life (beta-clearance) in huma ns than IgG3. Therefore the isotype was switched to an IgG1 by ligation of the 2F5 heavy chain variable region to an IgG1 constant region and expresse d as IgG1 kappa in CHO cells. CHO clones have been established, which stabl y express humAb 2F5 at high levels. The specificity, affinity and in vitro function of both isotypes were identical. (C) 2000 John Wiley & Sons, Inc.