CHOPPI : Chinese Hamster Ovary Protein Predicted Immunogenicity is a new informatics tool to assess the immunogenic risk of host cell protein (HCP) contaminants in the protein production process.


Despite ongoing process improvements in manufacturing, host cell protein (HCP) process impurities remain a substantial risk for biological products. Even at low levels, residual HCPs can induce a detrimental immune response, compromising the safety and efficacy of a biologic. Consequently, advanced-stage clinical trials have been cancelled due to the identification of antibodies against HCPs. Chinese Hamster Ovary cell lines are commonly used in the manufacturing of protein therapeutics; despite mammalian origin CHO contaminants can still present a significant immunogenicity risk.

CHOPPI is an interactive database of immunogenicity data for known CHO proteins developed by researchers at Dartmouth, EpiVax and University of Rhode Island. The database combines targeted search filters to narrow the results to the most likely HCP contaminants and immunogenicity analysis using EpiMatrix and JanusMatrix.

Because CHO proteins are mammalian in origin many of the epitopes found in CHO contaminants are similar to those found in human proteins and thus less likely to drive an adverse immune response. By utilizing T cell cross-reactivity analysis from JanusMatrix, the CHOPPI database can identify the number of more dangerous CHO-unique epitopes found within a potential contaminant.

CHOPPI has already generated a lot of interest from protein engineers and manufacturers for it’s potential to streamline and improve protein manufacturing safety measures. If you are interested in accessing CHOPPI for academic research please go to the CHOPPI website hosted by URI.

CHOPPI is not yet available for commercial users but will be released to beta testers over the next few months. If you are interested in learning more about CHOPPI please contact us.