Removal Of Host Cell Proteins During Monoclonal Antibody Purification

Protein A chromatography is a widely used and highly successful method of purifying recombinant monoclonal antibodies. However, since Protein A has high affinity for antibodies, harsh conditions such as low pH are often required to elute monoclonal antibodies from Protein A affinity columns. As a result, many proteins will denature and aggregate during this step, leading to lowered production yields, protein purity, and increased production costs.

Removing host cell proteins by depth filtration will significantly reduce the amount of proteins precipitated during the elution step from Protein A columns.

Recently several papers have been published regarding host cell proteins. One of these papers describes that adsorptive depth filters with positive charge were capable of removing particulates such as cell debris and capturing host cell proteins during monoclonal antibody purification. The paper further demonstrates that removing host cell proteins prior to loading Protein A columns resulted in significant reduction of protein precipitation during Protein A elution step. Lastly, 3M Purification 90ZA depth filters were shown to outperform Millipore™ A1HC depth filters in removing host cell proteins and reducing protein precipitation.