Rapid and Cost-Effective Diagnostic System for Sexually Transmitted Infections

DESCRIPTION (provided by applicant): According to the CDC, chlamydia and gonorrhea, caused by Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), respectively, are the first and second most frequently reported STIs in the US and likely the rest of the world. These STIs are often under-diagnosed, leading to delayed treatment, continued spread and higher public healthcare costs (~ 14.7 billion annually). As a result of their prevalence and long term health consequences, there is a need for rapid, sensitive methods of detecting STIs in order for patients to get results and treatment immediately. It is important that patients receive test results and initial consultation or treatment during the first patient visit, as they rarely return for a second visit. Point-of-care (POC) tests are an important strategy to address the STI epidemic, and because many affected by STIs (young and/or poor) often have limited access to traditional healthcare, POC tests that can be performed in non-traditional settings (university clinics, community public health care clinics, jails, detention centers) could greatly reduce STIs. The aim of this proposal is to develop a rapid, easy-to-use, inexpensive diagnostic system for identifying STI pathogens such as CT and NG. The systemwill combine Lynntech's novel nucleic acid amplification and lateral flow detection devices and can be used in many non-traditional healthcare settings. In Phase I, a high performance, low-cost thermal gradient cycler (TGC) will be developed. It will perform rapid polymerase chain reaction (PCR) for CT/NG targets in a simplified architecture that creates a stable thermal gradient from a single heat source. It addresses problems common to many thermal cyclers, such as user interfacing, sample loading, reliability and reproducibility. The TGC will be coupled with a lateral flow strip component for detecting PCR amplicons, and this component is incorporated into a standard 0.2-mL PCR tube, which is used in the TGC during PCR. This elegant integration allows the amplification and detection to be performed in a closed system, eliminating post- PCR contamination, and it permits a non-technical user to easily read and interpret results without sample transfer or special instrumentation. It will be demonstrated thatthe entire assay can be completed in less than 45 min, including sample preparation. When combined with an appropriate sample preparation module (also being developed by Lynntech), the system could serve as a POC device for rapid diagnosis of STIs. The proposed work will be carried out in collaboration with experts from various fields, including Charlotte Gaydos (STI expert, Johns Hopkins University), GuoDong Liu (nanomaterials and lateral flow assay, North Dakota State University), Victor Ugaz (fluidic/thermal characterization, Texas AandM University), and Yi-Wei Tang (clinical sample preparation, Vanderbilt University). To assist with technology commercialization, Diagnostic Consulting Network, Inc will provide consultation, as they have expertise in lateral flow assay design and manufacturing. The successful development and commercialization of our technology will impact how sophisticated molecular diagnostic assays can be implemented in POC or non-traditional healthcare settings. PUBLIC HEALTH RELEVANCE: Chlamydia and gonorrhea are the most common sexually transmitted infections (STIs) in the US, causing serious long term health problems such as sepsis, stricture disease, pelvic inflammatory disease (PID), ectopic pregnancy and infertility. This project will advance the development of a POC molecular diagnostic device for the rapid and inexpensive screening of STIs in non-traditional healthcare settings. Lynntech will build a very low cost ( 75 parts), automated thermal gradient cycler (TGC) to perform up to 16 polymerase chain reactions in less than 25 min. Additionally, Lynntech will combine this TGC technology with a lateral flow test technology for PCR amplicon detection. This low cost (lt 2), 5-min lateral flow disposable device is specificallydesigned to perform closed-tube molecular detection. If properly coupled with a sample preparation method, these two innovative technologies will yield a 45-min molecular test to identify STI pathogens in order for patients to receive immediate treatment before they leave a healthcare facility.