Revista de SIDA e investigación clínica

Molecular Validation of Putative Antimicrobial Peptides for Improved Human Immunodeficiency Virus Diagnostics via HIV Protein p24

Abstract

Monray Edward Williams, Marius Tincho, Musa Gabere, Ashley Uys, Mervin Meyer and Ashley Pretorius

Objective: Various HIV diagnostic systems are available however; the p24 antigen detection assay is preferred due to its ability to decrease the window period for HIV detection. The p24 antigen assay has been associated with low sensitivity. Antimicrobial Peptides (AMPs) display huge potential in development of more effective diagnostics tools. The aim of this study was to design derivative AMPs from AMPs identified previously, using an in silico approach, as templates, with higher predicted binding affinity for the p24 protein and implement the best suited AMPs in a Point-Of- Care (POC) device for detection of HIV-1 and HIV-2.

Method: This study firstly used an in silico approach to identify derivative AMPs which bind the N-terminal domain of the p24 antigen with increased predicted binding affinity. The in silico approach used the parental AMPs as templates for generation of the derivative AMPs through site-directed mutagenesis, 3-D structure prediction and docking studies. Secondly, the binding between the synthetically synthesized AMPs and the HIV antigen p24 was validated by an in house Lateral Flow Device (LFD) “on/off” binding experiment. The most promising AMPs were conjugated to gold nanoparticles (AuNPs) and implemented in a LFD to detect HIV-1 and HIV-2 using patient sera as well as a panel of international HIV standards (panel C10).

Result: With conjugation of AMPs to gold nanoparticles, parent AMP 1 and derivative AMP 1.1 used in combination most sensitively detected the recombinant protein p24 and was therefore selected for development of a LFD prototype for HIV diagnostics. Global HIV-1 (C10) and HIV-2 (C10) standards were successfully detected by the LFD prototype as well as HIV infected serum samples.

Conclusion: A sensitive HIV-1 and HIV-2 LFD prototype was developed which would within 15 minutes provide patients with accurate and sensitive diagnosis of HIV.