- RFP Year2020
- Awarded Amount$974,619
- Development StageTarget Identification
- Collaboration PartnersHokkaido University, Harvard University, Nagoya University, Research Institute of Tuberculosis , University of Minnesota , Fujita Health University
Introduction and Background of the Project
Mycobacterium tuberculosis (Mtb) is responsible for 10 million cases of active tuberculosis (TB) and nearly 1.4 million deaths annually. Mainly due to the long history of using anti-tuberculosis drugs, and insufficient access to and delivery of care, drug resistant Mtb is prevalent as of today. The emergence of multi-drug resistant (MDR; resistant to isoniazid and rifampicin) and extensively drug-resistant (XDR; resistant to isoniazid, rifampicin, a fluoroquinolone (levofloxacin or moxifloxacin), and at least one of bedaquiline or linezolid) strains of Mtb now jeopardizes the efficacy of the existing treatment. Despite the magnitude of this problem, there is a limited number of "new" anti-tubercular drugs to recently enter clinical trials.
This project aims to identify novel targets for TB drugs that can rapidly and strongly kill Mtb through two independent antimicrobial mechanisms (dual-acting). We have already identified such dual-acting candidate genes. In this project, we will characterize our candidate genes in vitro and in vivo to prioritize them within our discovery pipeline.
We will utilize a newly developed gene silencing technology for Mtb, the mycobacterial CRISPR interference (CRISPRi) system, to characterize our candidate genes in vitro and in vivo. Once we genetically validate our candidate genes, we will perform small-scale screenings using our in-house unique small molecule library (the ITbM chemical library). We will employ our unique whole cell target assays to identify small molecules that kill Mtb due to inhibition of one of our genetically validated targets. The identified hit compounds will be clustered by structural similarity and representative molecules of each cluster will be derivatized. These compounds will be used as probe compounds to perform chemical validation of the genetically validated targets.
How can your partnership (project) address global health challenges?
While any effective anti-tuberculosis therapy will hold an important place in maintaining the TB status quo, drugs that are potently bactericidal against MDR and XDR strains of Mtb are essential to eliminate this global health threat. Thus, this project aims to develop novel TB drugs with strong bactericidal activity against Mtb including MDR and XDR strains. At the completion of our project, we expect to identify multiple targets that are ready for large-scale screening efforts.
What sort of innovation are you bringing in your project?
Our ongoing study has led us to discover a unique strategy to kill TB rapidly and strongly (dual-acting) and this is what we are proposing as our candidate genes. Our project is innovative because we will utilize a cutting-edge genetic technology, CRISPR interference technology that allow us to characterize our unique and attractive candidate genes within a short amount of time.
Role and Responsibility of Each Partner
Our team consists of highly skilled experts in bacterial genetics, bacterial physiology, chemical biology, medicinal chemistry, and pharmaceutical sciences. Dr. Yusuke Minato (Fujita Health University) will be responsible for the project management and constructing CRISPRi mediated gene silencing strains of Mtb. Drs. Yusuke Minato and Satoshi Mitarai (Research Institute of Tuberculosis) will characterize the CRISPRi mediated gene silencing Mtb strains in vitro. Dr. Eric Rubin (Harvard University) will be responsible for characterizing selected CRISPRi mediated gene silencing Mtb strains in vivo. Dr. Ayato Sato (Nagoya University) will provide the small molecule library. Drs. Yusuke Minato, Satoshi Mitarai, and Ayato Sato will develop small molecule screening assays and perform the library screening. Drs. Satoshi Ichikawa (Hokkaido University) and Courtney Aldrich (University of Minnesota) will derivatize hit compounds. Drs. Yusuke Minato, Satoshi Mitarai, and Anthony Baughn (University of Minnesota) will assess the activities of hit compound and their derivatives against Mtb clinical isolates in vitro.