Real-time and Label-free Monitoring of Monoclonal Antibody Secretion Rate Using a PC-TIR Sensor

Introduction: Monoclonal antibodies (mAbs) are essential biotherapeutics for a wide range of diseases. However, the high demand and large amounts required present the need for new technologies in ensuring efficient, economical, and consistent production processes. One of the needs in mAb production is finding the cells that have high secretion rates. Current methods for monitoring mAb production rates face limitations in real-time accuracy and efficiency, necessitating the development of advanced monitoring techniques.

Materials and

Methods: We developed a novel system combining a photonic crystal-total internal reflection (PC-TIR) sensor with a µ-transwell chip for label-free, real-time detection of mAb secretion rates. The µ-transwell chip, consisting of PDMS and a PET porous membrane, was designed to facilitate continuous monitoring of mAb secretion from hybridoma cell lines. The system was assembled by bonding the PC-TIR biosensor to the µ-transwell chip and optimized for real-time detection using specific blocking and functionalization techniques. We first assessed the system's performance in detecting soluble proteins using different concentrations of IgG and BSA. Then, we optimized the detection of mAbs in real time using W6/32 hybridoma cells. We further assessed the impact of varying fetal bovine serum (FBS) concentrations in the culture media on mAb secretion. Finally, we evaluated the mAb secretion rates from different hybridoma cell lines raised against the same immunogenicity.

Results, Conclusions, and Discussions: The PC-TIR biosensor demonstrated high sensitivity in detecting protein secretion, with resonance shifts correlating to BSA and IgG concentration in solution. Real-time monitoring of mAb secretion from hybridoma cells revealed a direct relationship between cell concentration and detected protein levels. The system effectively differentiated secretion rates among various hybridoma cell lines and showed enhanced mAb secretion with higher fetal bovine serum (FBS) concentrations in the culture media. These results underscore the sensor's capability for high-resolution, real-time monitoring of mAb production. The integrated PC-TIR system provides a significant advancement in mAb production monitoring, offering real-time, label-free detection of secreted antibodies. This innovation has the potential to improve efficiency and quality control in mAb manufacturing, reducing costs and optimizing resource use.

Acknowledgements (Optional): The authors acknowledge funding from the National Institutes of Health (TR003148 and GM126571). J.-W. Y. acknowledges financial support from the National Science and Technology Council (NSTC 112-2917-I-564-015), Taiwan.