RT-LAMP-CRISPR-Cas13a technology as a promising diagnostic tool for the SARS-CoV-2 virus

Abstract

At the end of 2019, the new coronavirus, SARS-CoV-2, began a pandemic that persists to date and which has caused more than 6.2 million deaths. In the last couple of years, researchers have made great efforts to develop a diagnostic technique that maintains high levels of sensitivity and specificity, since an accurate and early diagnosis is required to minimize the prevalence of SARS-CoV-2 infection. In this context, CRISPR-Cas systems are proposed as promising tools for development in diagnostic techniques due to their high specificity, highlighting that Cas13 endonuclease discriminates single nucleotide changes and displays a collateral activity against single stranded RNA molecules. With the aim of improve the sensitivity of the diagnosis, this technology is usually combined with isothermal pre-amplification reactions (SHERLOCK, DETECTR). Basing on this, we have developed an RT-LAMP-CRISPR-Cas13a for SARS-CoV-2 virus detection in nasopharyngeal samples without using RNA extraction kit that exhibited 100 % specificity and 83 % sensitivity, as well as a positive predictive value of 100 % and a negative predictive value of 100%, 81%, 79.1% and 66.7 % in <20 Ct, 20-30 Ct, >30 Ct and total Ct values, respectively.

«Application of RT-LAMP-CRISPR-Cas13a technology to the detection of OXA-48 producing Klebsiella pneumoniae»

“…In a recent study, our group developed an RT-LAMP-CRISPR-Cas13a technique for the detection of SARS-CoV-2 in nasopharyngeal samples after a process in which no RNA extraction is needed, with the results revealed in HibriDetect strips and yielding 83 % sensitivity and 100 % specificity [22]. Here, we applied this technology to clinical samples from different origins, leading to the successful differentiation of K. pneumoniae from other species of the genus Klebsiella, as well as detection of the carbapenem-resistance gene bla OXA - 48 (Figure 1).…”