Alphalyse presents at BEBPA Conference in Lisbon

Combining Platform ELISA and Mass spectrometry for HCP analysis of low molecular weight host cell proteins

Ejvind Mortz, COO at Alphalyse, together with David Chimento from Rockland immunochemicals presented on Day 1 of the annual BEBPA HCP conference in Lisbon on May 17-19. The topic was “HCP Analysis of a small drug-protein in process sample by Combining Platform Immunoassays and Mass Spectrometry”. The topic was further discussed in two scientific posters, presented by Rikke Lund, research scientist at Alphalyse.

“Combining the strengths of platform ELISA and MS orthogonal HCP detection methods enabled a convenient, high throughput detection strategy for drug protein impurities. It holds the capabilities to visualize, quantify and identify host cell proteins. Both in the inprocess sample as well as the null cell lysate”, explains Rikke Lund.

“Futhermore, the use of LC-MS/MS (Liquid chromatography tandem mass spectrometry) has proven to be a very effective method for detecting small HCPs”.

The content of low molecular weight host cell proteins (HCPs) in protein drugs is often difficult to evaluate. Commonly used expression organisms, such as E. coli and Hamster cells, contain 30-40% proteins with a molecular weight below 20kDa. You easily miss these in gel separations, Western blots and ELISA HCP quantitation. As a result of useing GeLC-MS/MS, we identified HCPs that covered 99% of the entire E. coli proteome in terms of molecular weight and pI.

Eventually, the obtained protein identity enables an in-depth analysis of each individual HCP and a more detailed risk assessment.