Schalken J, Van Binsbergen J, Jacobs A, Reddy R, Dettmann C, Siebelink A, Van De Heijden J, Bruynis F, Van De Graaf M; International Conference on AIDS.

Int Conf AIDS. 2000 Jul 9-14; 13: abstract no. TuPeA2996.

J. Schalken, Organon Teknika, Boseind 15, 5281 RM Boxtel, Netherlands, Tel.: +31 411 65 43 53, Fax: +31 411 65 44 27, E-mail: j.schalken@teknika.btl.akzonobel.nl

Background: The 4th generation Ag/Ab combi assay Vironostika HIV Uni-Form II Ag/Ab was shown to reduce the seroconversion window with 65%, from 6 days to 2 days (Van Binsbergen et al., 1999, J. Virol. Meth. 82, 77-84) by incorporation of HIV p24 Ag detection in an a-HIV assay. Methods: In a continuing effort to enhance the safety of blood supply further, the sensitivity of the antigen detection part of the assay was improved by optimizing the critical detergent concentrations in the sample dilution medium. A clinical panel containing 19 early (Abbott Prism HIV-1/-2 negative, HIV p24 Ag positive) infections, obtained from South Africa (Natal Blood Transfusion Service), and 12 commercially available seroconversion panels (BBI and NABI), were tested. Results: The assay has an analytical sensitivity of 50 pg/ml (DuPont p24 Ag). The positive percentage in the South Africa clinical panel increased from 16 to 63% (tested in 1/10 dilution). To calculate the window phase reduction in comparison with a single p24 Ag assay, 12 panels with sampling intervals > 7 days were used. Because of this improved p24 antigen sensitivity, the Vironostika HIV Uni-Form II Ag/Ab assay closes the Ag positive/Ab negative seroconversion window almost completely, because 85% of the Ag+ phase is now being detected (65% in the current Ag/Ab). Conclusion: Sensitivity improvement of the HIV Uni-Form II Ag/Ab reduces the seroconversion window further. Expressed in days: of the 6.0 days comprising Ag-positive window phase, 5.0 days are covered (4.0 days with current Ag/Ab). The anti-HIV-1/-2 and anti-HIV-O sensitivity as well as the specificity of the improved HIV Ag/Ab combi remains fully equivalent to that of the current HIV Ag/Ab.

Publication Types:

• Meeting Abstracts

Keywords:

• AIDS Vaccines
• Acquired Immunodeficiency Syndrome
• Antibodies
• HIV Antibodies
• HIV Infections
• HIV Seropositivity
• HIV-1
• HIV-2
• Immunologic Techniques
• Sensitivity and Specificity
• South Africa
• organization & administration

Other ID:

• GWAIDS0001351

UI: 102238842

From Meeting Abstracts