title: An immunoligand assay for quantitation of process specific Escherichia coli host cell contaminant proteins in a recombinant bovine somatotropin.
abstract: We have developed a Threshold System immunoligand assay for the quantitation of residual, process-specific, Escherichia coli host cell contaminant proteins (HCP) in somavubove (a normal sequence recombinant bovine somatotropin). The assay has a dynamic range of 2 to 160 ng/mL, with a limit of quantitation of 2 ng/mL. Daily analytical precision (CV) for six replicates of the designated somavubove laboratory standard is 3.0%. Cumulative analytical precision for multiple assay runs of this standard (a total of 69 laboratory standard replicates) is 8.4%. A conservative alert limit of 100 ng/mL has been assigned in order to assure analytical precision for each assay sample under conditions of stoichiometric antibody excess. Although the assay was designed for use as a profile-release specification assay, it has also been used to validate removal of HCP by the proprietary somavubove purification process. This use is consistent with regulatory guidelines related to "well characterized" recombinant biopharmaceutical proteins.
authors.affiliation: Pharmacia and Upjohn, Inc., Pharmaceutical Development-Biotechnology, Kalamazoo, MI 49001, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Whitmire
authors.forename: L C
authors.initials: LC
authors.lastname: Eaton
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001426:Bacterial Proteins / Q000032:analysis* / Q000276:immunology; D002417:Cattle; D002478:Cells, Cultured; D004340:Drug Contamination; D004926:Escherichia coli / Q000276:immunology*; D013006:Growth Hormone / Q000276:immunology*; D007118:Immunoassay / Q000379:methods* / Q000592:standards; D007202:Indicators and Reagents; D008024:Ligands; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D007202:Indicators and Reagents; D008024:Ligands; D013006:Growth Hormone