Document 2736
 DOCN  M94A2736
 TI    HIV-1 p24 quality assurance and standardisation of enzyme immuno assays.
 DT    9412
 AU    Best SJ; Healey DS; Silvester C; Dax EM; National HIV Reference
       Laboratory, Fairfield Hospital, Australia.
 SO    Int Conf AIDS. 1994 Aug 7-12;10(1):236 (abstract no. PB0375). Unique
       Identifier : AIDSLINE ICA10/94369839
 AB    AIMS: (i) To evaluate antigen assays for quantitative use with and
       without immune complex disruption (ICD). (ii) To compare quantitative
       results of quality assurance (QA) samples. (iii) To investigate whether
       results obtained from different assays show improved comparability when
       the same antigen standard is used to construct the standard curve in
       each assay. METHODS: Five commercial p24 antigen assays were evaluated
       using four p24 antigen preparations and 150 sera from HIV-1 positive
       subjects, all in dilution series. The antigen preparations included one
       recombinant protein (American Biotechnologies, Inc.) and three from
       viral lysate. A whole viral lysate preparation from CSL Limited
       (CSL-071) was chosen as a potential standard for national use in antigen
       assays and sent, with three QA samples to the four laboratories of the
       Clinical Trials Group. Results of QA samples were calculated from the
       standard curves provided in the kits as well as from the standard curve
       constructed from the CSL-071 dilution series. RESULTS: All assays
       provided approximately linear results (correlation coefficients
       0.96-0.99) with all antigens. This was not always true when ICD
       procedures were used. The range of antigen concentrations over which the
       readings were linear varied between native and recombinant antigens:
       6-100 pg/ml and 10-1,000 pg/ml respectively. Results of QA samples
       calculated from the CSL-071 dilution series were comparable between
       laboratories and between assays but when calculated from kit standard
       curves showed wide variation (e.g. mean 66pg/ml range 60-72pg/ml vs
       100pg/ml with range 52-134pg/ml). CONCLUSIONS: (i) p24 EIAs are
       generally suitable for quantitation but not always with ICD procedures.
       (ii) Viral lysate and recombinant antigens behave differently in p24
       antigen assays. (iii) Standard antigen preparations may be the most
       appropriate method to achieve reproducible results.
 DE    Comparative Study  Human  HIV Core Protein p24/*BLOOD  HIV
       Seropositivity/*DIAGNOSIS/IMMUNOLOGY  HIV-1/*IMMUNOLOGY  *Immunoenzyme
       Techniques  Predictive Value of Tests  *Quality Assurance, Health Care
       MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).