Host cell protein

Host Cell Protein (HCP) is a term used in biopharmaceutical manufacturing to refer to the residual proteins produced by the host organism that are not the intended therapeutic protein product. These proteins are considered impurities and their removal is a critical aspect of the protein purification process.

Overview

In the production of recombinant proteins, the host organism (often Escherichia coli or Chinese hamster ovary cells) is engineered to express a protein of interest. However, the host organism also produces its own proteins, which can contaminate the product. These are known as host cell proteins.

Detection and Quantification

Several methods are used to detect and quantify HCPs in the final product. These include enzyme-linked immunosorbent assay (ELISA), mass spectrometry, and western blot analysis. Each method has its own advantages and limitations, and the choice of method often depends on the specific requirements of the product and the regulatory authorities.

Removal

The removal of HCPs is a critical step in the purification process. This is typically achieved through a combination of chromatography techniques, such as ion exchange chromatography, size exclusion chromatography, and affinity chromatography. The efficiency of HCP removal can be influenced by several factors, including the nature of the HCPs, the properties of the therapeutic protein, and the conditions of the purification process.

Regulatory Considerations

The presence of HCPs in the final product is a concern for regulatory authorities such as the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). These agencies require that manufacturers demonstrate that HCP levels are below a certain threshold and that the HCPs present do not pose a risk to patient safety.

See Also

• Biopharmaceutical
• Protein purification
• Recombinant DNA