Liquid competition radioimmunoassay for the detection and quantification of the human immunodeficiency virus p24 antigen in serum

Among the less costly viral assays that may be appropriate for resource-poor countries, the workshop steering committee (A meeting organized by the Forum for Collaborative HIV Research April 22, 2002 Washington, DC) selected the heat-denatured p24 assay for consideration at this meeting because of its advanced stage of development. Developed by Jorg Schupbach (University of Zurich), this assay for HIV p24 antigen is more sensitive than the original p24 assay used as a viral marker in early clinical trials of HIV therapies. The assay uses heat denaturation in a conventional p24 antigen Elisa assay. Boiling for 5 minutes destroys antibody and preserves antigen. Our test called phi CGEACRENK HIV-p24 RIA" is a transposition of signal-amplification-boosted of head-denatured plasma Elisa (1) to a radioimmunoassay performed with in-house reagents. The radioimmunoassay technique is based on the competitive binding of the serum HIV-1 p24 and radiolabel recombinant p24 preparation. They compete for binding to an antibody specific present in a substoichiometric amount. Complex of radiolabeled and unlabeled p24 antigen were separated from unbound species by reaction with an anti-rabbit sheep immunoglobulin as second antibody (house made). The detection limit of p24 was 0.05 pg/ml with as little as 10 ul of serum. This paper describes, for the first time, the successful production of polyclonal antisera specific for HIV-1 p24 and the radio iodination of recombinant HIV-1 p24 using exhaustive chloramin-T oxidation and the development of a sensitive radioimmunoassay (RIA) for measuring HIV-1 p24 in serum. (c) 2007 Elsevier Masson SAS. Tous droits reserves.