P15.06 Molecular validation of putative antimicrobial peptides for improved human immunodeficiency virus diagnostics via hiv protein p24

Abstract

Introduction The Human Immunodeficiency Virus-1 (HIV-1) is responsible for causing Acquired Immunodeficiency Syndrome (AIDS), and to date remains a pandemic. More than 40 million people are infected globally, with 60% of the infected people residing in Sub-Saharan Africa. Earlier detection translates into earlier treatment, which ensures improved quality of life. However, difficulties remain in the field of HIV diagnostics. The p24 antigen detection tests are preferred due to its ability to decrease the window period. The current p24 diagnostic assay displays great insensitivity, due to the p24 antibody produced by the body, binding to the C-terminal of the p24 antigen. This interaction obstructs detection, the basis of the current p24 test. Using in silico approaches, novel antimicrobial peptides (AMP) were identified which bind to the N-terminal, instead of the C-terminal domain (antibody binding pocket) of the p24 antigen (provisional patent). This is important because if the p24 antibody binds to the C-terminal, the unoccupied N-terminal domain would provide a binding pocket for the AMP. Successful conjugation of nanoparticles to the positively validated AMP, can lead to the development of a diagnostic lateral flow device. Methods In silico site-directed mutagenesis and docking studies to identify additional AMPs that bind the N-terminal domain of protein p24 with increased binding affinity. Preliminary study: Lateral flow design with identified AMPs to test HIV positive sera. P24 recombinant protein expression. P24 protein-AMP binding studies. Results In silico studies identified 9 AMPs which could be used to bind p24 antigen for HIV diagnostics. Preliminary study: Lateral flow successfully detected HIV in HIV positive sera. Successful p24 recombinant protein expression. Successful validation of binding AMPs against the p24 protein. Conclusion Binding interaction between AMPs and p24 protein is validated. Subsequently a sensitive lateral flow device could be developed that successfully detects HIV in positive HIV sera. Disclosure of interest statement All research has been funded by the National Research Foundation and Nanotechnology Innovation Centre. No commercial funding has been provided for this study.