Hamster (CHO) Cathepsin B - Recombinant

Recombinant Hamster (CHO) Cathepsin B (CTSB) is a lysosomal cysteine protease widely recognized for its crucial role in intracellular protein degradation and turnover. Unlike other cathepsins, CTSB is unique for its dual activity as both an endopeptidase and a carboxypeptidase, enabling it to break down proteins from within and from the carboxy-terminus.

 

This enzyme is involved in various physiological and pathological processes, including immune responses and several diseases like cancer and inflammation.

 

In biopharmaceutical production, particularly with CHO cells, residual Cathepsin B is considered a significant Host Cell Protein (HCP) impurity due to its proteolytic activity. The presence of even trace amounts of active Cathepsin B can potentially fragment or degrade the therapeutic protein product, negatively impacting its quality, efficacy, and patient safety.

 

One study found that CHO cathepsin B was responsible for the fragmentation of a target bispecific antibody. Therefore, careful monitoring and effective removal of Cathepsin B, along with other HCPs, are critical throughout the bioprocessing and purification steps to ensure product integrity and patient safety.