Human anti-HIV IgM detection by the OraQuick ADVANCE® Rapid HIV 1/2 Antibody Test

Abstract

The Centers for Disease Control and Prevention (CDC) and many public health jurisdictions continue to advocate for the most sensitive rapid HIV test that is available. Currently, the recommendation is to utilize tests that can detect HIV infection biomarkers within 30 days of infection, when initial immune responses are mounted. The infected patient's IgM response is often used to detect acute infection within a 20-25 days window after infection. This requirement applies to lab-based testing with automated analyzers and rapid, point of care (POC) testing used for screening in a non-clinical setting. A recent study has demonstrated that POC tests using a Protein A-based detection system can detect samples with predominantly HIV-1 IgM reactivity (Moshgabadi et al., 2015). The OraQuick ADVANCE® Rapid HIV-1/2 Antibody Test (OraQuick ADVANCE®) also uses Protein A as the detection protein in the antibody-binding colloidal gold conjugate, so it is expected that the OraQuick ADVANCE® Test will also detect samples with predominantly IgM reactivity. This report definitively demonstrates that the OraQuick ADVANCE® Test can detect IgM antibodies during an acute infection window period of approximately 20-25 days after infection, and is therefore suitable for use in testing environments requiring adherence to current CDC recommendations.

Keywords: CDC; HIV; IgM detection; POC; Rapid test; Seroconversion.

Figure 1. Various biomarkers utilized for HIV detection.

Stages of HIV life cycle (Fiebig stages) and relative abundance of biomarkers throughout these stages. Different biomarkers allow for detection of infection at different stages, represented by the boxes and labels below the chart. This figure is adapted from Fiebig et al. (2003).

Figure 2. Centers for disease control and prevention HIV testing algorithm.

Reproduced from laboratory testing for the diagnosis of HIV infection: updated recommendations, 2014.

Figure 3. Operating principle of the OraQuick ADVANCE® Test.

Sample is wicked up the device, hydrating blocker and conjugate pad reagents, which are transferred to the nitrocellulose membrane. HIV antibodies in the sample bind biotinylated reagents and are labeled by Protein A colloidal gold. The immuno-sandwich is immobilized by biotin binding with Streptavidin-BSA, and by anti-HIV antibodies interacting with anchored peptides at the test line. Human antibodies complexed with Protein A colloidal gold are captured at the control line. Accumulation of colloidal gold at the control and test lines creates a reddish-purple stripe.