Targeted Host Cell Protein Quantification by LC-MRM Enables Biologics Processing and Product Characterization

Area of Science:

• Biopharmaceutical analysis
• Mass spectrometry
• Protein quantification

Background:

• Multiple Reaction Monitoring (MRM) is a sensitive LC-MS technique widely used in pharma for molecule quantification.
• Its application for quantifying specific host cell proteins (HCPs) in bioprocesses remains underexplored.
• HCPs can impact biologics product quality, necessitating robust monitoring methods.

Purpose of the Study:

• To develop and validate a multiplex LC-MRM assay for simultaneous quantification of two high-risk lipases (PLBL2 and LPLA2).
• To assess the assay's performance for monitoring lipase clearance during biologics process development.
• To evaluate the impact of HCP-mAb interactions on lipase quantification.

Main Methods:

• Development of a multiplex LC-MRM assay targeting PLBL2 and LPLA2.
• Method qualification including linearity, precision, accuracy, selectivity, recovery, matrix effect, dilution linearity, and carryover.
• Comparison of direct digestion and affinity depletion platforms for HCP quantification.

Main Results:

• The LC-MRM assay demonstrated linearity over a dynamic range of 1 to 500 ng/mg.
• Comprehensive method qualification confirmed the assay's fitness for use and robustness.
• The assay effectively monitored the clearance of PLBL2 and LPLA2 during process development.
• Comparison revealed the impact of HCP-mAb interaction on lipase quantification.

Conclusions:

• The developed multiplex LC-MRM assay is a rapid and accurate tool for monitoring high-risk HCP clearance in bioprocesses.
• This assay can actively guide process improvement and optimization for enhanced biologics quality.
• Understanding HCP-mAb interactions is crucial for accurate lipase quantification.