Antibody reagents for your host cell protein assay: Experience counts

6 December 2023

In the world of biopharmaceuticals and bioprocessing, ensuring the quality, safety, and efficacy of biotherapeutic products is of paramount importance. Host cell proteins (HCPs) are a critical component to consider in this context. HCPs are proteins of the host cells, typically microbial, insect or mammalian, used in the manufacturing of biologics, such as monoclonal antibodies, recombinant proteins, and vaccines. These HCPs originate from a variety of cellular sources, including the cell membrane, cytoplasm, nucleus, mitochondria, and other cellular compartments.

HCPs can co-purify with the desired biologic product, posing risks in terms of immunogenicity, where they can trigger an immune response in patients, potentially leading to adverse reactions, reduced drug efficacy, or even life-threatening conditions. In addition, contaminating HCPs may carry risks of transferring pathogens.

Host cell protein antibody reagents are specific antibodies developed to detect and quantify the presence of HCPs in bioprocessing samples. These reagents play a crucial role in ensuring the quality and safety of biotherapeutic products by enabling the detection of minute traces of HCPs in the final product and process intermediates. Furthermore, HCP antibody reagents help measure the levels of HCP contamination throughout the bioprocess, allowing for timely corrective actions and ensuring they are within acceptable limits.

The HCP antibody reagents used to develop these assays continue to be one of the main limiting factors in increasing sensitivity and detecting different proteins. Reagent development approaches have varied dramatically from the use of commercial kits to process specific HCP antibodies for each therapeutic. Commercial kits may be used for HCP quantitation until process validation, but once a program advances to later stages of clinical development (i.e., Phase II/III), platform-specific or process-specific HCP antibody reagents should be generated.

Successful antibody generation efforts often lack a consistent, robust and effective approach to generate antibodies sensitive enough to meet the lower levels of quantitation required by regulatory bodies as well as ability to detect a broad range of possible HCP contaminants. Gene therapy products present additional complications when developing these antibody reagents and specific experience dramatically increases the chances of a successful project. Unlike monoclonal antibody therapeutics, the gene therapy products often use human cells to grow the viral vectors. The corresponding host cell proteins are very poor immunogens which make it even more challenging to raise antibodies with good coverage of HCPs. The sensitivity and specificity of the assays are only as good as the antibody reagents that are used to run them.

Leveraging experience, optimized techniques and procedures, and the integration of various strategies for over 150 anti-HCP reagent projects, we generate quality antibody reagents with much higher success rates, increased sensitivity, broader coverage and higher yields.

Antibody Reagent and Vaccine Experience – >150 Anti-HCP Reagent Projects


Need help with your HCP reagent project?

Whether your project uses host cell expression systems derived from bacterial, mammalian, yeast, plant or insect cells, contact us today to discuss your project needs.