A comparative study of monoclonal antibodies (Mabs) purified from cell culture supernatant on EDTPA-modified zirconia beads and protein A-hyper D support

摘要

Colloidal zirconia was spray dried to yield zirconia particles, which were further modified with N,N,N',N'-Ethylenediamine tetra methylenephosphonic acid (EDTPA) to yield a support for use in bioseparations. EDTPA modified zirconia particles will be further referred to as, r_PEZ. Cell culture supernatants rich in monoclonal antibody (Mab) subtypes IgG(1), IgG(2a), IgG(2b), and IgG(3) were chromatographed on a r_PEZ column, and on a protein A-hyper D column that was purchased commercially. All Mab subtypes bound to r_PEZ and process yields in the range of 88 to 99% were obtained. The purity of the Mab products were ascertained by gel electrophoretic analysis and were estimated to be greater than 95%. The purified Mab products obtained from r_PEZ and protein A columns were compared to the reference Mab standard in biological and enzymatic assays. The value of the dissociation constant (K-d ) was found to be comparable and was in the range to that obtained with reference Mab standard (0.231 +/- 0.03 M). In addition, Mabs purified with r_PEZ had the same deglycosylation profile as the reference Mab standard. Thus, it appears that the r_PEZ purified Mab is similar in activity to Mab purified with a protein A support and in addition, the zirconia surface does not adversely impact the activity of the purified Mab.