Affiliation:
1. Department of Immunology, Associated Regional and University Pathologists, Salt Lake City, UT 84108.
Abstract
Three procedures for the removal of immunoglobulin G (IgG) from human serum were evaluated for their effectiveness in eliminating false-positive results caused by rheumatoid factor and in removing IgG from serum to reduce competing-IgG interference in IgM enzyme-linked immunosorbent assay (ELISA) testing. The procedures investigated employed two anti-human IgG diluents and a recombinant protein G-filled tube. The anti-human IgG was more effective than the protein G method in eliminating false-positive results caused by rheumatoid factor and removed 5.4% more IgG from serum samples in the normal range (< 1,700 mg/dl) and up to 16.4% more of the IgG from samples with elevated levels (> 1,700 mg/dl). The recombinant protein G removed less IgM than the anti-human IgG diluents; however, this difference did not affect the results of the ELISA. For these reasons, the in-house-developed anti-human IgG diluent proved to be the most effective and economical for IgM serological testing.
Publisher
American Society for Microbiology
Subject
Microbiology (medical),Clinical Biochemistry,Immunology,Immunology and Allergy
Reference11 articles.
1. A physicochemical study of protein G: a molecule with unique immunoglobulin G-binding properties;Akerstrom B.;J. Biol. Chem.,1986
2. Protein G: a powerful tool for binding and detection of monoclonal and polyclonal antibodies;Akerstrom B.;J. Immunol.,1985
3. International reference preparation of rheumatoid arthritis serum;Anderson S. G.;Bull. W. H. O.,1970
4. A routine diagnostic test for IgA and IgM antibodies to rubella virus: adsorption of IgG with Staphylococcus aureus;Ankerst J.;J. Infect. Dis.,1974
5. Purification and some properties of streptococcal protein G: a novel IgG-binding reagent;Bjorck L.;J. Immunol.,1984