I-Corps: Cell-based Platforms for Protein Cleavage Targeted Dengue and Zika Virus Drug Discovery

San Diego State University Foundation, San Diego CA

Investigators

Abstract

The broader impact/commercial potential of this I-Corps project is to provide cell-based systems that enable the discovery of drugs that offer therapeutic solutions to combat emergent viral contagions, most notably, Dengue Fever and Zika. Presently, the lack of suitable engineered cell systems that enable screening is a primary impediment to drug discovery. The technology targets inhibition of viral protein cleavage, which is essential to viral function. The biological targets have successful therapeutic and commercial precedent in HIV. The cell based systems not only enable the selection of promising drug leads, but also reduce the incidence of false positive and toxic leads with impact on time and cost. The technology is generally applicable and can be easily adapted to different viral proteins, strains or diseases of therapeutic interest. The technology also has immediate applications in therapeutic discovery for Alzheimers and cancer. This I-Corps project is a consequence of the development of a unique cell-based assay platform that monitors proteolytic cleavage events with fluorescence, when protease activity is inhibited. Previous assays of protease inhibition were typically associated with loss, rather than gain of signal, which resulted in the detection of many false positive leads as a consequence of compound associated, non-selective, or toxic behavior. The fluorescence can be detected by flow cytometry or fluorescent microscopy, and is easily adapted to non-fluorescent luminescence in plate-reader formats. The assay system is robust and applicable to antiviral drug discovery. The technology enables targeting to the appropriate cellular compartment and has the ability to multiplex targets. Originally developed and validated in the HIV-1 protease and HIV-1 envelope protein, has now been successfully adapted and screened against Dengue virus. The assay system is easily adaptable to other important human viral pathogens including Chikungunya and Zika and their associated serotypes, and is equally applicable to other therapeutic opportunities.