Development of specific host cell protein assays

Abstract: The manufacturing and the development of biotherapeutic drugs involves the expression of biotherapeutic proteins in a host cell expression system followed by a purification process. Bioanalytical methods to measure impurities such as host cell proteins (HCPs) are needed to obtain a robust process and a safe drug according to regulatory requirements. The aim of this project was to develop three specific HCP assays for detection and quantification of specific HCPsusing the Gyrolab® platform. The HCPs (Annexin A5, Clusterin and Nidogen-1) chosen for this project are generated from Chinese hamster ovary (CHO) cells. Each assay was evaluated on four different Gyrolab® BioaffyTM CDs with a comparison of column profiles, accuracy, precision and sensitivity. For each assay the best suited CD type was suggested together with possible upper limit of quantification (ULOQ) and lower limit of quantification (LLOQ) within the estimated detection range. The results indicate that the CHO Annexin A5 assay has a detection range extending from 1500 ng/ml to 2.1 ng/ml, with possible ULOQ at 1000 ng/ml and LLOQ at 3.2ng/ml using the BioaffyTM 4000 HC CD. The CHO Clusterin assay has a detection range extending from 1500 ng/ml to 0.4 ng/ml, with possible ULOQ at 1000 ng/ml and LLOQ at 0.7 ng/ml using the BioaffyTM 4000 HC CD. The CHO Nidogen-1 assay has a detection range extending from 1500 ng/ml to 0.1 ng/ml, with ULOQ at 1000 ng/ml and LLOQ at 0.2 ng/ml using the BioaffyTM1000 CD.