An enzyme immunoassay for the detection of staphylococcal protein A in affinity-purified products.
Rabbit antiserum, specific for protein A from Staphylococcus aureus, was conjugated to alkaline phosphatase and used in a double antibody solid-phase enzyme immunoassay. The assay was developed to monitor eluate from a large-scale protein A-Sepharose affinity column used to purify monoclonal antibodies for human clinical trials. The assay detected soluble protein A in the presence of immunoglobulin at concentrations as low as 4 ng/ml. Analysis of the product purified by affinity chromatography revealed the presence of protein A at ng/ml concentrations. The assay developed here can provide a reliable and convenient method for detecting soluble protein A.
D000469:Alkaline Phosphatase; D000915:Antibody Affinity; D002846:Chromatography, Affinity / Q000379:methods; D004306:Dose-Response Relationship, Immunologic; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000276:immunology; D013205:Staphylococcal Protein A / Q000032:analysis*
D007074:Immunoglobulin G; D013205:Staphylococcal Protein A; D000469:Alkaline Phosphatase