ARTICLE FROM QKINE

Unexpected consequences: growth factor cross-contamination in mammalian and E. coli expressed growth factors

Qkine published an article highlighting the critical issue of cross-contamination in commercially available recombinant growth factors, which can lead to irreproducible results and incorrect scientific conclusions. The author, Liz Stewart, the Head of Marketing and Scientific Communications of Qkine, emphasizes that this problem occurs in proteins derived from both mammalian and E. coli expression systems.

Key examples of contamination includes:

• TGF-β1 in Mammalian-Expressed GDF-15
• IL-4 in E. coli-Expressed IL-17F

The article argues that preventing such contamination requires a significant improvement in manufacturing and quality control standards across the industry. Qkine, an ISO 9001:2015 certified company based in Cambridge, UK, advocates for stringent measures, including:

Strict Process Controls: Implementing and following complete Standard Operating Procedures (SOPs), ensuring full raw material traceability, and using dedicated purification columns for each protein to prevent cross-contamination.

Rigorous Lot-Specific Quality Control: Beyond standard checks, this must include quantitative bioassays to confirm expected activity and rule out off-target effects, as well as mass spectrometry to detect even low levels of protein contaminants.

In essence, the article serves as a cautionary tale for researchers to be aware of potential contaminants in recombinant proteins and a call to action for manufacturers to adopt more stringent production and quality assurance protocols to ensure the purity and reliability of their products.