Clinical feasibility for CRISPR-based COVID-19 testing validated
A project to develop a new, low-cost, CRISPR-based diagnostic platform to detect infectious diseases, including the HIV virus and SARS-CoV-2 was started in March. The project was carried out by researchers in the Department of Biomedical Engineering. As of now, for the rapid detection of infectious diseases, this method is one step closer to being a cutting-edge diagnostics technology.
All-In-One-Dual CRISPR-Cas12a (AIOD-CRISPR) method allows simple, rapid, ultrasensitive, visual detection of SARS-CoV-2. This method is aimed for use at home or in small clinics, said Changchun Liu, associate professor.
The results of the study are published in the journal Nature Communications. Using COVID-19 clinical swab samples, the researchers validated the clinical feasibility of the platform. Furthermore, to detect clinical sample results within 20 minutes, a low-cost hand warmer was used as an incubator.
Liu said that the usage of disposable hand warmers to heat the AIOD-CRISPR assay eradicates the requirement for costly electric tools, allowing instrument-free point of care molecular diagnostics of COVID-19.
The study was co-authored by postdoctoral researchers Xiong Ding and Kun Yin, professor, and Associate Dean for Research Dr. Rajesh Lalla, Dr. Enrique Ballesteros, associate professor and chair, pathology and laboratory medicine, Ph.D. student Ziyue Li, and Assistant professor in pathology and laboratory medicine Dr. Maroun Sfeir.
Presently, for early detection of pathogens, nucleic acid amplification testing (PCR/RT-PCR) is the most sensitive and specific method. However, it is not suitable for rapid point-of-care diagnostics due to the necessity for specific trained technicians and laboratory equipment. Real-time monitoring is needed for highly contagious pathogens to prevent viral spread from individual to individual.
The All-In-One-Dual-CRISPR method using the RNA extract of 28 clinical COVID-19 swab samples, including 8 COVID-19 positive samples were assessed by Liu and his team. Each sample was tested twice in two independent trials to ensure the reliability of detection. Within 40 minutes, all 8 COVID-19 positive samples were detected as positive. This was also confirmed by visual detection and the CDC-approved RT-PCR method.
Additionally, to eliminate the need for an electric incubator, the team used a low-cost hand warmer as an incubator to detect the patient samples. On an air-activated hand warmer, the AIOD-CRISPR tubes were directly placed, and the outcomes were visible by the naked eye under the LED light. Within 20 minutes, 2 positive samples of COVID-19 incubated in the hand warmer bag were visually detected and identified as a positive sample.
Liu stated that the rapid and early diagnostics of COVID-19 and other infectious diseases can be provided at home or clinics by such a simple, portable, and sensitive detection platform.
Clinical feasibility for CRISPR-based COVID-19 testing validated
Author: Sruthi S
