More than 4 million people in the United States are infected with chlamydia (CT) and gonorrhea (NG). These sexually transmitted infections (STIs) have few early symptoms but cause serious complications that range from sterility and infertility to multidrug resistance and increased HIV infection and transmission. Reducing the spread of these STIs will require early diagnosis, and treatment of infected individuals. Success requires the wide availability of low-cost, robust, and easy to use molecular diagnostics for use at the point-of-care (POC) for the earliest detection of the causative organism. We have developed sample-to-answer molecular diagnostic assays for CT and for NG detection in simulated urine. The hypothesis to be tested is that molecular diagnostic chips can detect and differentiate CT and NG in microliter-scale human urogenital samples with specificity and sensitivity better than presently available POC testing. We have previously demonstrated at the bench that the components of the chip work with simulated samples. Our goal is to develop a portable, inexpensive molecular diagnostic that can be used at the POC to diagnose and differentiate CT and NG infections. We have teamed up with Dr. Charlotte Gaydos at Johns Hopkins University Center for Point-of-Care Technologies Research for Sexually Transmitted Diseases to perform an intermediate sized sensitivity and specificity study using previously collected and stored urogenital specimens that have been de-identified and well characterized. We will develop a low-cost, integrated sample-to-result molecular diagnostic assay system to detect chlamydia and gonorrhea that uses a simple, visual means of detecting nucleic acid amplification products. In order to develop this technology for real-world clinical and field use, the following aims are proposed: 1. To adapt our current test to a multiplexed CT and NG assay, we will optimize sample preparation, amplification, and detection of CT, NG, and a competitive internal control (CIC). 2. To enable testing at the POC, we will optimize the chip design and instrumentation to integrate sample-to-answer processes. 3. To clinically validate the new POC molecular diagnostic, we will determine if the integrated assay is comparable in specificity and sensitivity to gold standard real- time NAATs using human urogenital samples. The ultimate deliverable of the project is a fully-integrated, clinically validated molecular diagnostic for POC testing of STI that is ready for commercialization and scale- up to prospective clinical trials.
Effective control of the spread of sexually transmitted infections requires widespread availability of inexpensive and accurate diagnostics for early detection. We will develop an integrated multiplexed molecular diagnostic test with simple Yes/No visual detection of pathogens. Such an innovation will reduce the costs of molecular testing while improve access to high quality diagnosis of sexually transmitted infections.
|Katevatis, Constantinos; Fan, Andy; Klapperich, Catherine M (2017) Low concentration DNA extraction and recovery using a silica solid phase. PLoS One 12:e0176848|