Development and evaluation of a differential diagnostic test strip for antibodies induced by HIV-1 vaccine and natural infections

Abstract

Objective To develop a differential diagnostic kit for distinguishing antibodies induced by HIV-1 infection and HIV-1 vaccine and evaluate its diagnostic performance. Methods Nitrocellulose membrane was coated with HIV-1 envelope protein gp41 and HIV-1 recognition fusion peptide SK1-SK2-SK3 obtained using a prokaryotic expression system. The differential diagnostic test strip for HIV-1 antibodies was prepared by assembling the coated membrane with a non-woven fabric coated with protein A-coupled colloidal gold. The performance of the test strip was evaluated using samples of HIV-positive sera, HIV-negative sera, HIV serum panel, HIV Tiantan vaccine sera and other cross-reactive sera, and the test results using this strip were compared with those by ELISA. Results The sensitivity of SK1-SK2-SK3 coating on the novel differential diagnostic test strip for HIV-1 antibody detection was 93.5%, with a detection specificity of 100.0%. When combined with gp41 coating, the test strip showed a diagnostic sensitivity of 100.0%. The test results with the strip were consistent with those by ELISA (P>0.05). For the Tiantan vaccine serum, the SK1-SK2-SK3 coating on the strip all yielded negative results without the false positive results of the gp41 coating. Conclusion This novel HIV-1 antibody diagnostic test strip can effectively distinguish the antibodies produced by HIV-1 infection from those generated by HIV-1 vaccination without false positive results as are common with the currently available commercial HIV test kits.

Keywords

• hiv-1
• natural infection
• vaccine
• antibody
• differential diagnosis
• diagnostic reagent kits