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Host Cell Protein Analysis using Enrichment Beads Coupled with Limited Digestion

Published: January 19th, 2024



1Analytical Chemistry, Regeneron Pharmaceuticals Inc.

A protocol is presented for enriching host cell proteins (HCPs) from drug products (DP) and detecting peptides using proteome enrichment beads. The method is demonstrated using an in-house manufactured monoclonal antibody (mAb) drug substance (DS), which is a well-characterized reference material for evaluating and comparing different methods in terms of performance.

Host cell proteins (HCPs) are impurities that can adversely affect therapeutic proteins, even in small quantities. To evaluate the potential risks associated with drug products, methods have been developed to identify low-abundance HCPs. A crucial approach for developing a sensitive HCP detection method involves enriching HCPs while simultaneously removing monoclonal antibodies (mAbs) before analysis, utilizing liquid chromatography-mass spectrometry (LC-MS).

This protocol offers detailed instructions for enriching host cell proteins using commercially available proteome enrichment beads. These beads contain a diverse library of hexapeptide ligands with specific affinities for different proteins. The protocol also incorporates limited digestion and subsequent peptide detection using nano LC-MS/MS. By employing these techniques, HCPs with low abundance can be enriched over 7000-fold, resulting in an impressive detection limit as low as 0.002 ppm. Significantly, this protocol enables the detection of 850 HCPs with a high level of confidence using a NIST mAb. Moreover, it is designed to be user-friendly and includes a video demonstration to assist with its implementation. By following these steps, researchers can effectively enrich and detect HCPs, enhancing the sensitivity and accuracy of risk assessment for drug products.

Host cell proteins (HCPs) are impurities that are released from the cell culture of the host organism and co-purified with monoclonal antibody (mAb)1,2,3,4. Trace levels of HCPs can negatively impact the quality of the drug product5,6,7,8,9,10,11,12,

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Abbreviations used in the protocol are listed in Supplementary Table 1.

1. Preparation of solutions and buffers

NOTE: The commercial details of all the reagents are listed in the Table of Materials.

  1. Prepare 0.1 M Tris-HCl, pH 8.0 solution by adding 1 mL of 1 M Tris-HCl, pH 8.0 into 9 mL of deionized water in a glass vial, and mix well by vortexing. Store at 4 °C for up to 3 months.
  2. Prepare.......

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This protocol presented a sample preparation workflow, termed protein enrichment coupled with limited digestion (PMLD), for the analysis of host cell proteins (HCPs) in a monoclonal antibody (mAb) sample. Figure 1 illustrates the step-by-step procedure of PMLD. The researchers compared the results of HCP analysis using direct digestion (shown in the top panel of Figure 2) and PMLD (shown in the bottom panel of Figure 2). The Total I.......

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There are two versions of commercially available protein enrichment beads: one with a smaller capacity and the other with a larger capacity (see Table of Materials). Both versions of the enrichment beads contain ten preps in the package. The manufacturer's instructions suggest that each prep from the small capacity kit can be used to enrich 10 mg of total protein. However, for optimal performance of host cell protein (HCP) enrichment from DS, each prep is good for five DS samples. Therefore, each kit can.......

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NameCompanyCatalog NumberComments
16 G, Metal Hub Needle, 2 in, point style 3Hamilton91016
Acclaim PepMap 100 C18 trap column (20 cm × 0.075 mm)Thermo Fisher164535
Acetonitrile with 0.1% Formic Acid (v/v), Optima LC/MS Grade Fisher-ScientificLS120-4
Amicon Ultra-0.5 Centrifugal Filter UnitMillipore SigmaUFC5010
C18 analytical column (0.075 mm × 1.7 μm × 30 cm, 100 Å)CoAnn TechnologiesHEB07503001718I
Centrifuge 5424Eppendorf5405000646
Dithiothreitol (DTT) Thermo FisherA39255
Frit for SPE cartridges, 9.5 mm, 3 mL, 100/pkAgilent12131020
GL-Tip GCGL Sciences Inc  7820-11201
in-house mAbRegeneronconcentration 200 mg/mL
Iodoacetamide (30 x 9.3 mg)Thermo FisherA39271
L-HistidineSigma AldrichH6034
L-Histidine monohydrochloride monohydrateSigma Aldrich53370
NanoDrop 2000Thermo ScientificND-2000
Orbitrap Exploris 480Thermo FisherBRE725539
Protein LoBind Tube 0.5 mLEppendorf (VWR)22431064
Protein LoBind Tube 2.0 mLEppendorf (VWR)22431102
Proteome Discoverer software 2.4Thermo Scientific
ProteoMiner Protein Enrichment Large-Capacity KitBio-Rad1633007
ProteoMiner Protein Enrichment Small-Capacity KitBio-Rad1633006
Sodium deoxycholate (SDC)Sigma AldrichD6750
Sodium lauroyl sarcosinate (SLS) Sigma AldrichL5777
Thermomixer REppendorf22670107
Trifluoracetic acid (TFA)Fisher-Scientific28904
Trypsin (Sequencing Grade Modified)  (5 x 20 ug)PromegaV5111
Tube Revolver RotatorThermo Fisher88881001
UltiMate 3000 RSLC nano systemThermo FisherULTIM3000RSLCNANO
UltraPure 1 M Tris-HCl pH 8.0Thermo Fisher15568-025
Vortex Genie 2VWR102091-234
Water with 0.1% Formic Acid (v/v), Optima LC/MS Grade Fisher-ScientificLS118-4 

  1. Aboulaich, N. A novel approach to monitor clearance of host cell proteins associated with monoclonal antibodies. Biotechnology Progress. 30 (5), 1114-1124 (2014).
  2. Goey, C. H., Alhuthali, S., Kontoravdi, C. Host cell protein removal from biopharmaceutical preparations: Towards the implementation of quality by design. Biotechnology Advances. 36 (4), 1223-1237 (2018).
  3. Levy, N. E., Valente, K. N., Choe, L. H., Lee, K. H., Lenhoff, A. M. Identification and characterization of host cell protein product-associated impurities in monoclonal antibody bioprocessing. Biotechnology and Bioengineering. 111 (5), 904-912 (2014).
  4. Molden, R. Host cell protein profiling of commercial therapeutic protein drugs as a benchmark for monoclonal antibody-based therapeutic protein development. MAbs. 13 (1), 1955811 (2021).
  5. Bee, J. S. Trace levels of the CHO host cell protease cathepsin D caused particle formation in a monoclonal antibody product. Biotechnology Progress. 31 (5), 1360-1369 (2015).
  6. Bracewell, D. G., Francis, R., Smales, C. M. The future of host cell protein (HCP) identification during process development and manufacturing linked to a risk-based management for their control. Biotechnology and Bioengineering. 112 (9), 1727-1737 (2015).
  7. Chiu, J., et al. Knockout of a difficult-to-remove CHO host cell protein, lipoprotein lipase, for improved polysorbate stability in monoclonal antibody formulations. Biotechnology and Bioengineering. 114 (5), 1006-1015 (2017).
  8. Gilgunn, S., et al. Identification and tracking of problematic host cell proteins removed by a synthetic, highly functionalized nonwoven media in downstream bioprocessing of monoclonal antibodies. Journal of Chromatography A. 1595, 28-38 (2019).
  9. Graf, T. Identification and characterization of polysorbate-degrading enzymes in a monoclonal antibody formulation. Journal of Pharmaceutical Sciences. 110 (11), 3558-3567 (2021).
  10. Hall, T., Sandefur, S. L., Frye, C. C., Tuley, T. L., Huang, L. Polysorbates 20 and 80 degradation by group XV lysosomal phospholipase A2 isomer X1 in monoclonal antibody formulations. Journal of Pharmaceutical Sciences. 105 (5), 1633-1642 (2016).
  11. Jones, M. 34;High-risk" host cell proteins (HCPs): A multi-company collaborative view. Biotechnology and Bioengineering. 118 (8), 2870-2885 (2021).
  12. Li, X., et al. Identification and characterization of a residual host cell protein hexosaminidase B associated with N-glycan degradation during the stability study of a therapeutic recombinant monoclonal antibody product. Biotechnology Progress. 37 (3), e3128 (2021).
  13. Zhang, S. Identification of the specific causes of polysorbate 20 degradation in monoclonal antibody formulations containing multiple lipases. Pharmaceutical Research. 39 (1), 75-87 (2022).
  14. Zhang, S., Xiao, H., Li, N. Degradation of polysorbate 20 by Sialate O-Acetylesterase in monoclonal antibody formulations. Journal of Pharmaceutical Sciences. 110 (12), 3866-3873 (2021).
  15. Zhang, S., Xiao, H., Molden, R., Qiu, H., Li, N. Rapid polysorbate 80 degradation by liver carboxylesterase in a monoclonal antibody formulated drug substance at early stage development. Journal of Pharmaceutical Sciences. 109 (11), 3300-3307 (2020).
  16. Gunawan, F. Comparison of platform host cell protein ELISA to process-specific host cell protein ELISA. Biotechnology and Bioengineering. 115 (2), 382-389 (2018).
  17. Chen, I. H., Xiao, H., Daly, T., Li, N. Improved host cell protein analysis in monoclonal antibody products through molecular weight cutoff enrichment. Analytical Chemistry. 92 (5), 3751-3757 (2020).
  18. Chen, I. H., Xiao, H., Li, N. Improved host cell protein analysis in monoclonal antibody products through ProteoMiner. Analytical Biochemistry. 610, 113972 (2020).
  19. Doneanu, C. E., et al. Enhanced detection of low-abundance host cell protein impurities in high-purity monoclonal antibodies down to 1 ppm using ion mobility mass spectrometry coupled with multidimensional liquid chromatography. Analytical Chemistry. 87 (20), 10283-10291 (2015).
  20. Huang, L., et al. A Novel sample preparation for shotgun proteomics characterization of HCPs in antibodies. Analytical Chemistry. 89 (10), 5436-5444 (2017).
  21. Johnson, R. O., Greer, T., Cejkov, M., Zheng, X., Li, N. Combination of FAIMS, Protein A depletion, and native digest conditions enables deep proteomic profiling of host cell proteins in monoclonal antibodies. Analytical Chemistry. 92 (15), 10478-10484 (2020).
  22. Kreimer, S. Host cell protein profiling by targeted and untargeted analysis of data independent acquisition mass spectrometry data with parallel reaction monitoring verification. Analytical Chemistry. 89 (10), 5294-5302 (2017).
  23. Madsen, J. A., et al. Toward the complete characterization of host cell proteins in biotherapeutics via affinity depletions, LC-MS/MS, and multivariate analysis. MAbs. 7 (6), 1128-1137 (2015).
  24. Nie, S. Simple and sensitive method for deep profiling of host cell proteins in therapeutic antibodies by combining ultra-low trypsin concentration digestion, long chromatographic gradients, and boxcar mass spectrometry acquisition. Analytical Chemistry. 93 (10), 4383-4390 (2021).
  25. Yang, F. Versatile LC-MS-Based workflow with robust 0.1 ppm sensitivity for identifying residual HCPs in biotherapeutic products. Analytical Chemistry. 94 (2), 723-731 (2022).
  26. Zhang, Q. Comprehensive tracking of host cell proteins during monoclonal antibody purifications using mass spectrometry. MAbs. 6 (3), 659-670 (2014).
  27. Zhang, S., et al. Putative phospholipase B-Like 2 is not responsible for polysorbate degradation in monoclonal antibody drug products. Journal of Pharmaceutical Sciences. 109 (9), 2710-2718 (2020).
  28. Zhang, J., He, J., Smith, K. J. Fatty acids can induce the formation of proteinaceous particles in monoclonal antibody formulations. Journal of Pharmaceutical Sciences. 111 (3), 655-662 (2022).
  29. Uniprot1. . , (2023).
  30. Uniprot2. . , (2023).

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