Rapid and Simultaneous Detection of IgG Antibodies to HIV-1 and HIV-2 by Dot Immunogold Filtration Assay

A simple rapid detection of HIV-1 and HIV-2 antibodies was developed by using dot immunogold filtration assay. Five recombinant proteins derived from HIV env and gag regions of HIV-1 and HIV-2 (P24, GP41, GP120C, GP120V3 and GP36) were expressed in E. coli. The proteins were purified, immobilized onto the nitrocellulose membrane and used for detecting anti-HIV IgG antibodies Human IgG was used as internal control. Anti-HIV antibodies detected in sera by these antigens were observed with the naked eye with the aid of colloidal gold labeled SPA. A total of 51 sera were tested by ELISA and by our rapid HIV assay. A total of 21 HIV positive samples (containing one HIV-1 positive control serum and one HIV-2 positive control serum) confirmed by Western blots exhibited a positive reaction when tested by our assay. HIV negative sear (30 samples) were also negative by our test. These results suggested that our method can be used for detecting anti-HIV antibodies and has the advanteage of quickness, simplicity and cost effectiveness. In addition, simultaneous detection and discrimination among four HIV markers (anti-P24, GP41, GP120 and GP36 antibodies) by the rapid HIV test would be useful for increasing the sensitivity and accuracy of this rapid test and for evaluating and monitoring infected individuals and identifying the risk of imminent progression to AIDS.